CN113597050A

CN113597050A - Control circuit, drive circuit, control method and lighting device

Info

Publication number: CN113597050A
Application number: CN202010514807.2A
Authority: CN
Inventors: 邵蕴奇; 徐勇
Original assignee: Shanghai Looall Electronics Co ltd
Current assignee: Shanghai Looall Electronics Co ltd
Priority date: 2019-06-06
Filing date: 2020-06-08
Publication date: 2021-11-02
Anticipated expiration: 2040-06-08
Also published as: CN113597050B

Abstract

The invention discloses a control circuit, a driving circuit, a control method and a lighting device, wherein the control circuit is used for controlling an electric loop formed by connecting a direct-current power supply and n LED groups in series and comprises a control unit and m sub-switch units; the sub-switch units respectively correspond to one LED group; the control unit respectively controls the on or off of the sub-switch units; when the output voltage of the direct current power supply is not less than the sum of the conduction voltage drops of the n LED groups, the control unit cuts off the m sub-switch units to form a main loop; when the output voltage is less than the sum of the conduction voltage drops of the n LED groups, the control unit conducts at least one sub-switch unit and cuts off the rest sub-switch units to form a sub-loop. The invention controls the on or off of the sub-switch unit under the condition that the output voltage of the direct current power supply is reduced, so that the LED can still be lightened under the condition that the output voltage is reduced.

Description

Control circuit, drive circuit, control method and lighting device

The present application claims priority from chinese patent application CN201910493482.1 filed 2019, 6/6.

The present application claims priority from chinese patent application CN201911106847.7 filed on 2019, 11/13/h.

The present application claims priority from chinese patent application CN201911106813.8 filed on 2019, 11/13/h.

The present application claims priority from chinese patent application CN201911106939.5 filed on 2019, 11/13/h.

The present application claims priority from chinese patent application CN201911106790.0 filed on 2019, 11/13/h.

The present application claims priority from chinese patent application CN201911107801.7 filed on 2019, 11/13/h.

This application claims priority to chinese patent application CN202010340456.8, filed on even 4/27/2020.

This application claims priority to chinese patent application CN202010507672.7, filed 6/5/2020.

The present application refers to the above-mentioned chinese patent application in its entirety.

Technical Field

The invention relates to the field of LED illumination, in particular to a control circuit, a driving circuit, a control method and an illumination device.

Background

An LED (light emitting diode) is a mainstream light emitting element at present, and a change in voltage and current on the LED can cause a change in the light emitting amount of the LED, so that a desired current is applied to the LED to form an on-state voltage drop to obtain a desired light emitting amount, which is one of important design indexes of a driving circuit.

Fig. 1 is a graph of the parameters of an LED rated at 9V and 60mA, from which it can be seen that the LED has a conduction voltage drop of about 9V to achieve the desired 60mA drive current. When the voltage across the LED is reduced, the driving current of the LED is reduced, the power of the LED and the luminous brightness of the LED are also reduced, but the power and the luminous brightness of the LED and the driving current of the LED are not in a linear proportional relation. In other words, when the driving current flowing through the LED decreases, the voltage across the LED decreases, and the power and the light emission luminance of the LED also decrease, and vice versa.

Through the search of the prior art, the conventional driving circuit is mostly shown in fig. 2 or fig. 3. The driving circuit of fig. 2 stabilizes the light emission luminance by controlling the current flowing through the LED. As shown in fig. 2, the utility power VACA forms a dc power supply through the filtering of the rectifier bridge DBA and the electrolytic capacitor CA, outputs a pulsating dc voltage VRECA to supply power to the LEDA, wherein the LEDA is composed of one or more LEDs connected in series or in parallel, and the voltage reference VA, the operational amplifier EAA, the MOS transistor QA, and the resistor RSA form a current source UA. When the pulsating dc voltage VRECA is larger than the conduction voltage drop VLEDA of LEDB, the current through LEDA is controlled to a stable value by the current source UA.

The driving circuit of fig. 3 achieves input power stabilization by controlling the power variation flowing through the LEDs. As shown in fig. 3, the utility power VACB forms a dc power supply through the filtering of the rectifier bridge DBB and the electrolytic capacitor CB, outputs a pulsating dc voltage VRECB to supply power to the LEDB, wherein the LEDB is formed by connecting one or more LEDs in series or in parallel, and the voltage reference VB, the operational amplifier EAB, the MOS transistor QB, the resistors RSB and R2 form a current source UB, and further includes a resistor R1 and a capacitor CF to detect and filter the signal of the pulsating dc voltage VRECB. When the pulsating direct current voltage VRECB is greater than the conduction voltage drop VLEDB of LEDB, the current flowing through LEDB decreases as the pulsating direct current voltage VRECB increases, and vice versa, achieving stable input power.

However, when the pulsating dc voltage VREC is decreased, as shown in fig. 4, when the pulsating dc voltage VREC is decreased to be lower than the conduction voltage drop VLED of the LED, the LED will become dark and even not be lit, or the current of the LED increases and decreases periodically (corresponding to the power frequency 50/60HZ), so that a low-frequency strobe is generated, the depth of the strobe decreases with the decrease of the mains voltage, and usually, when the mains voltage decreases by 10%, the depth of the strobe exceeds 10%, which affects the lighting effect of the lighting device.

Disclosure of Invention

It would be beneficial if the tolerance (tolerance) of a plurality of LED groups/arrays coupled in series-parallel to variations in the supply voltage could be facilitated to be increased, i.e. to tolerate a wider range of variations in the supply voltage.

It would be beneficial if the tolerance (tolerance) of a plurality of LED arrays coupled in series-parallel to variations in the supply voltage could be facilitated to be increased, i.e. to tolerate a wider range of variations in the supply voltage.

Floating/common ground circuit structure

In one embodiment of the present invention, a lighting load control circuit for driving an array of n lighting loads powered by a dc power source is provided, the lighting load control circuit comprising:

a control unit;

m switching units configured to respectively correspondingly couple m of the n light emitting loads when the control circuit drives/is applied to the n light emitting loads, respective control terminals of the m switching units being respectively connected to the control unit, controlled by the control unit to bypass the corresponding light emitting loads;

wherein m and n are integers, n is more than or equal to 2, m is more than or equal to 1, and m is less than or equal to n.

Alternatively, the light emitting load is a Light Emitting Diode (LED), an OLED, a polymer light emitting diode, or the like.

Further alternatively, the method, apparatus, device, etc. of any embodiment in the present application, which are exemplified by LED-based loads, may be applied to lighting loads, solid-state lighting loads, etc., and further, the words "LED", "LED array (or also referred to as" LED group ") and the like in any embodiment of the present invention may be replaced by lighting loads, solid-state lighting loads, lighting units, solid-state lighting units, etc.

Optionally, each lighting load, solid state lighting load or LED array may comprise a plurality of LED units, for example: a plurality of LED units in series, a plurality of LED units in parallel, and a plurality of LED units combined in series and parallel.

Optionally, in another embodiment of the present invention, a control circuit for an array of LEDs is further proposed, for driving an array of n LEDs coupled to each other (e.g., connected in series) and powered by a dc power supply, the control circuit comprising:

a control unit;

m switching units (or simply switches) configured to: when the control circuit is applied to (or integrated with) the n LED arrays, x of the m switch units are respectively (e.g., one-to-one) connected in parallel (or coupled in parallel) to x of the n LED arrays, and the remaining m-x switch units are respectively bridged between a) (a connection point between (adjacent) two of the m-x n LED arrays, and B) a common ground connection point (or bypass connection point).

Wherein the common ground connection point is located between the n LEDs (as a whole) and the output of the dc power supply. The control terminals of the m switch units are respectively connected to the control unit. n is more than or equal to 2, m is more than or equal to 1, n is more than or equal to m and more than or equal to x is more than or equal to 0, and x, m and n are integers.

Alternatively, if the m switching cells are N-type devices, the common ground connection point may be located: i) after the current outflow ends of the n LED arrays, 2) between the current outflow ends of the n LED arrays and the negative polarity output end of the dc power supply, or 3) (when a series circuit formed by the n LED arrays and the dc power supply operates) between the last LED array in the n LED arrays in the current direction and the negative polarity output end of the dc power supply. Alternatively, the x switching cells may also be arranged at least partially upstream of the m-x switching cells in the current direction.

Alternatively, if the m switching cells are P-type devices, the common ground connection point may be located: i) before the current inflow end of the n LED arrays, or 2) between the current inflow end of the n LED arrays and the positive polarity output end of the direct current power supply, or 3) between the first LED array and the positive polarity output end of the direct current power supply in the current direction when the n LED arrays are all conducted. Alternatively, the x switching cells may be arranged at least partially downstream of the m-x switching cells in the current flow direction.

Optionally, in another embodiment of the present invention, a control circuit for an array of LEDs is further proposed, for driving an array of n LEDs coupled to each other (e.g., connected in series) and powered by a dc power supply, the control circuit comprising: a control unit and m switching units. m switching units configured to: when the control circuit is applied to (or integrated with) n LED arrays, x switch units of the m switch units are respectively (e.g., one-to-one) connected in parallel (or coupled in parallel) to x LED arrays of the n LED arrays, and the remaining m-x switch units are respectively bridged between a) m-x connection points, and B) a common ground connection point (or bypass connection point).

Wherein these m-x connection points are located between (adjacent) two of the n LED arrays/between two each other. The common ground connection is between the n LEDs (as a whole) and the output of the dc power supply. The control terminals of the m switch units are respectively connected to the control unit. n is more than or equal to 2, m is more than or equal to 1, n is more than or equal to m and more than or equal to x is more than or equal to 0, and x, m and n are integers.

Alternatively, if the m switching cells are P-type devices, the common ground connection point may be located: i) before the current inflow end of the n LED arrays, or, 2) between the current inflow end of the n LED arrays and the positive polarity output end of the dc power supply, or 3) between the LED arrays at the first position along the current direction and the positive polarity output end of the dc power supply when the n LED arrays are all turned on. Alternatively, the x switching cells may be arranged at least partially downstream of the m-x switching cells in the current flow direction.

In one embodiment of the present invention, there is provided a control circuit for driving n LED arrays supplied by a dc power supply, the control circuit comprising:

a control unit;

the m switch units are configured to be respectively correspondingly coupled with the m LED arrays in the n LED arrays when the control circuit drives the n LED arrays, and the control ends of the m switch units are respectively connected to the control unit and controlled by the control unit to bypass the corresponding LED arrays;

wherein m and n are integers, n is more than or equal to 2, m is more than or equal to 1, and m is less than or equal to n. In addition, the control circuit can also be referred to as a driving control circuit in other embodiments.

Alternatively, the dc voltage may be from an energy storage device such as a battery, and may be a stable voltage, a constant voltage.

Of course, it should be understood that: although some embodiments of the present invention describe the related methods, devices, apparatuses, circuits, etc. with respect to the rectified ripple power, these embodiments can also be applied to general periodically-varying power, non-periodically-varying power, unstable power with voltage ripple, etc., or various modifications can be formed for these diversified variable and constant powers based on these embodiments, and the methods, devices, apparatuses, circuits, etc. in these modifications are all within the protection scope of the claims of the present invention.

Alternatively, in N LED arrays connected in series, the P pole (or positive pole) of each LED array may be connected to the N pole (or negative pole) of the LED array adjacent to it.

Optionally, in the control circuit of some embodiments, the m switching units bypass the corresponding one or more LED arrays by being controlled by selective conduction of the control unit. By turning on various possible combinations of the m switch units, different bypass loops (or sub-loops) and bypass loop currents therein are selectively established (enabled). If the m switch units are not conducted, a first loop (or called as a main loop) formed by the direct-current power supply and all the n LED arrays works.

Optionally, in the control circuit of some embodiments, x switch units of the m switch units are correspondingly (e.g., in a one-to-one correspondence) connected in parallel with x LED arrays of the m LED arrays, and the remaining m-x switch units are respectively and correspondingly connected across one end of the remaining m-x LED arrays of the m LED arrays and the dc power output terminal, where x is an integer, m is greater than or equal to 2, and m is greater than or equal to x is greater than or equal to 0. The m-x common ground switches may be directly connected to the dc power output terminal in a common ground manner, or may be indirectly connected to the dc power output terminal through a current limiting device (e.g., a current limiting resistor, a controlled current source) in the first loop, an LED array that is not bypassed, and other circuit units. Optionally, in the control circuit of some embodiments, the m-x switch units may be respectively turned on to allow a Loop back (Loop back to) of the dc power supply from a corresponding end of each of the m-x LED arrays to form a common ground bypass path (bypass path), so that a current may flow from a positive polarity end of the dc power supply, through a corresponding end of one of the m-x LED arrays, and back to a negative polarity end of the dc power supply. Of course, the m-x common ground switch units may be connected to the current limiting device prior to the common ground, and indirectly coupled/connected to the common ground or the power supply output terminal via the current limiting device.

Alternatively, if the m switching units are N-type devices, when the control circuit is connected to and drives the N LED arrays, the x LED arrays, the m-x LED arrays, and the current limiting device are sequentially arranged along the current direction, respective positive polarity ends of the m-x switching units are respectively connected to anodes of the corresponding LED arrays, and respective negative polarity ends of the m-x switching units are connected between the current limiting device and a negative electrode of the dc power supply; wherein x is an integer, m is more than or equal to 2, and m is more than or equal to x and more than or equal to 0.

Optionally, in the case that m switching units are N-type devices, the LED array and the current limiting device corresponding to/coupled with the m switching units are sequentially disposed along the current direction, wherein two ends of x switching units are both connected to the upstream of the current limiting device, and two ends of the remaining m-x switching units are respectively connected to the upstream and the downstream of the current limiting device, wherein x is an integer, m is greater than or equal to 2, and m is greater than or equal to x is greater than or equal to 0.

Optionally, in the case that m switching units are P-type devices, the current limiting device and the LED array corresponding to/coupled with the m switching units are sequentially disposed along a current direction, wherein two ends of x switching units are both connected to a downstream of the current limiting device, two ends of the remaining m-x switching units are respectively connected to an upstream and a downstream of the current limiting device, wherein x is an integer, m is greater than or equal to 2, and m is greater than or equal to x is greater than or equal to 0.

Among them, in view of the characteristics of their connection relationship, x switching cells may be referred to as floating switching cells, and the remaining m-x switching cells among the m switching cells may be referred to as common ground switching cells.

Optionally, the m switching units are NPN, N-type devices, and respective ports (e.g., current input/anode, or current output/cathode) of the m-x LED arrays are respectively coupled to the dc power supply through the corresponding switching units. Alternatively, in a first loop where the dc power supply supplies n LED arrays in series, the floating switches may be interleaved with the common ground switches, for example: the floating switch unit → the common ground switch unit → the floating switch unit → the common ground switch unit. The floating switching units may also be partly or entirely arranged before the common ground switching unit, i.e. between the common ground switching unit and the dc power supply, or upstream in the current direction, so that these floating switching units are not influenced/bypassed by the common ground switching unit.

Optionally, the m switching units are PNP, P-type devices, and respective ports (e.g., current input/anode, or current output/cathode) of m-x LED arrays of the m LED arrays that can be bypassed are respectively coupled to the dc power supply through the corresponding switching units. Alternatively, in a first loop in which the dc power supply supplies n LED arrays in series, the floating switch may be arranged in a unit interleaved with the common switch unit. The floating switching units may also be partly or fully arranged between the common ground switching unit and the dc power supply, i.e. downstream in the direction of the current, so that these floating switching units are not affected/bypassed by the common ground switching unit.

Optionally, the m switching units are NPN, N-type devices, and at least a part of the x switching units and the m-x switching units are sequentially connected in series along the current direction. Alternatively, a current limiting device may be provided in series with the n LED arrays in the first loop, for example, between the n LED arrays and the negative dc output of the dc power supply, the positive pole of each of the n LED arrays being connected to the negative pole of its adjacent LED array. Further alternatively, if the control circuit couples m LED arrays through m switch cells, the n-m LED arrays not coupled may be connected in series between the positive polarity end of the dc power supply and the LED array coupled with the m switch cells, i.e. the n-m LED arrays not bypassed are connected in series in the first loop at a position closer to the positive polarity end of the dc power supply.

Optionally, in the control circuit of some embodiments, x is 0, and the m switching units are all common-ground switching units.

Optionally, in the control circuit of some embodiments, m-x > 0, and the m switching units are all floating switching units.

Optionally, in the control circuit of some embodiments, m > x > 0, the m switching cells include both floating and common ground switching cells.

Alternatively, the value of x may be relatively small. For example: 5 > x > 0, 4 > x > 0, 3 > x > 0 or 2 > x > 0, making it easier for the control circuit to be integrated in one chip (chip) in case the number x of floating switch cells is smaller or the number of floating switch cells is smaller than the common ground switch cells, thereby obtaining a cost advantage because the floating switch cells cannot be connected in common ground, need to be isolated/insulated from each other, and are relatively low in manufacturability. In contrast, the common ground switch or the common ground bypass circuit is easier to integrate and lower in cost. However, the floating switch unit only bypasses the LED array connected in parallel therewith when conducting, and does not bypass the other LED arrays at the same time, whereas the common ground switch unit may bypass all the LED arrays behind its connection in the main loop. In contrast, when the output voltage of the dc power supply is low and insufficient to support simultaneous conduction of all the LED arrays, the common-ground switch unit may bypass a part of the LED arrays, and in the same case, the floating-ground switch unit may selectively conduct different combinations of the LED arrays according to the requirements under different dc power supply voltages, and in cooperation with a proper design, may conduct n LED arrays at least once within one period of the power supply voltage. This more flexible control capability of the x (floating) switch units for the lighting loads may be used in conjunction with a timer or other devices to support the (active) control of the bypass loop and the on/off state of the bypassed lighting loads at a certain frequency to form the alternate lighting of the corresponding lighting loads, and the frequency of this alternate lighting may be set to a higher frequency, for example, several tens of kHz, to reduce the low-frequency stroboscopic of the lighting loads, which is also applicable to the control circuit, the driving circuit, the lighting device, and the driving/controlling method in other embodiments.

Optionally, the m switching units are respectively controlled by the control unit, and are switched to two states of on and off, or may also have or be switched to a third state: as a linear current source for the regulating current (control current or process of variation of the control current).

Optionally, the control circuit in some embodiments further includes a current limiting device connected in the control circuit, for example, in series in the first loop, so that when the control circuit drives the n LED arrays, a series loop is formed with the n LED arrays and the dc power supply.

Optionally, the current limiting device is connected in series in the first loop, and is also connected in series with the n LED arrays, and the position of the current limiting device in the first loop (or the main loop) is not limited, for example, the current limiting device may be between the n LED arrays and the negative polarity output terminal of the dc power supply, or may be between the n LED arrays and the positive polarity output terminal of the dc power supply. The first loop is referred to herein as the main loop, the series loop, in other embodiments.

Optionally, in the control circuit in some embodiments, the current limiting device and at least part of the m switching units are configured to independently or jointly regulate the current flowing through at least part of the n LED arrays.

Optionally, in the control circuit in some embodiments, the current limiting device and at least part of the x (floating) switching units are configured to regulate the current flowing through at least part of the n LED arrays independently or jointly.

Optionally, the current limiting device has a control terminal connected to the control unit, the current limiting device and/or at least part of the m switching units being operable to regulate the respective currents in accordance with a control signal at the respective control terminal.

Optionally, the current limiting device has a control terminal connected to the control unit, and the current limiting device and/or at least part of the x (floating) switch units are operable to regulate the respective currents in accordance with control signals of the respective control terminals, thereby regulating the currents in the bypass loops in which the switch units are located.

Alternatively, m is greater than or equal to 2 and greater than or equal to 1, and n is greater than or equal to 2. The control circuit includes:

a first pin configured to couple a positive polarity output terminal of a dc power supply or a positive polarity terminal of a first LED array of the n LED arrays to the outside;

a second pin configured to externally couple a negative polarity end of a first LED array and a positive polarity end of a second LED array of the n LED arrays;

a third pin configured to couple a negative polarity output terminal of the dc power supply to the outside;

A fourth pin configured to couple a negative polarity end of a second LED array of the n LED arrays to the outside;

and the number of the first and second groups,

a positive polarity terminal of a first switch cell (e.g., one of the x floating switches or one of the m-x common ground switches) of the m switch cells is connected to the second pin, and a negative polarity terminal of the first switch cell is coupled to the third pin.

Optionally, the positive polarity terminal of the current limiting device is connected to the fourth pin; the negative terminal of which is connected to the third pin. Optionally, the third pin is grounded. The negative polarity terminal of the first switching unit is directly connected to the third pin. Alternatively, the negative polarity terminal of the first switching unit may also be indirectly connected/coupled to the third pin, i.e.: the negative polarity terminal of the first switching unit is connected to the fourth pin and is coupled to the third pin through a current limiting device. Optionally, the m switch units further include a second switch unit, and a positive polarity end of the second switch unit (for example, one of the x floating switches) is connected to the first pin; the negative polarity terminal of the second switching unit is connected to the second pin.

Alternatively, the current limiting device may be connected in series in the first loop in other manners, for example, the positive polarity terminal of the current limiting device is connected to the first pin; the negative polarity end of the first LED array is connected with the positive polarity end of the first LED array; and the negative polarity end of the first switch unit is directly connected to the third pin. Alternatively, the current limiting device may also be connected between the second pin and the negative polarity end of the first LED array, or between the second pin and the positive polarity end of the second LED array, in a direction consistent with the current flow.

Optionally, the n LED arrays further comprise a third LED array, i.e., m 2, n 3; the third LED array can be connected in series in the main circuit, and is not bypassed by any switching unit, and can maintain a normally bright state at a voltage level of a general dc power supply (for example, the voltage level of the dc power supply is at least higher than a conduction voltage drop of the third LED array), thereby improving energy conversion efficiency of the n LED arrays.

Optionally, the control circuit in some embodiments, further includes: the current limiting device comprises a first carrier and a second carrier which are electrically isolated from each other, wherein the second carrier is configured to carry a second switch unit, the first carrier is configured to carry a first switch unit, and the current limiting device and the control unit are arranged on the first carrier or the second carrier. Further alternatively, i) the first carrier and its carried circuit units/devices, 2) the second carrier and its carried circuit units/devices, both may be manufactured as one integrated circuit device, e.g. a package based on a dual base island frame.

Optionally, the control circuit in some embodiments further includes one or more current programming interfaces, which are respectively disposed in the current limiting device or one or more of the m bypasses corresponding to the m switching units. Further optionally, the current programming interface/interfaces is/are provided in the circuit of the current source in the respective current limiting device or the respective bypass, being part of the current limiting device or the respective current source. For example, a first current programming interface is configured to receive a first resistance that is operably connected from a periphery (peripheraly). The current regulation performance of the current source in the main loop and/or the bypass loop can be controlled by the first resistor, and further, the current or the power in the corresponding main loop/bypass loop can be limited/regulated. Further optionally, the current programming interface may include a fifth pin and/or a sixth pin that are externally provided, so that when a user of the control circuit uses the control circuit to manufacture a lighting device/lamp, a resistor with a certain resistance value is connected between the fifth pin and the sixth pin according to requirements such as power, and thus, the current/power of the bypass loop is set, and the power of the lamp can be configured in a customized manner in a manufacturing process. Of course, the second current programming interface can be disposed in the second switch unit, which is not described herein. In addition, it can be understood that: the sixth pin may be connected to a power ground, in which case only one pin, for example the fifth pin, is required to cooperate with the power ground (or be considered as the sixth pin), together receiving the first resistor which is operatively connected from the periphery (peripheraly).

Further, it would be beneficial in the context of power supply voltage variations if the power/luminous flux stabilization capability (capability for stabilization) of multiple LED arrays coupled in series-parallel could be facilitated to accommodate a wider range of power supply voltages.

For this reason, in the control circuit of another embodiment of the present invention, with respect to a pulsating direct-current voltage output by the direct-current power supply being an unstable electric power having a voltage ripple, the control unit is configured to: the current in the one or more switching units or current limiting devices that are turned on is regulated to vary in the opposite direction of the voltage (e.g., turn-on voltage drop) experienced by the pulsating dc voltage/n LED arrays. In other words, the current flowing through one or more LED arrays in the n LEDs, which are in a conducting state, or in a bypass loop (or shunt loop), is dynamically adjusted by one or more switching units or current limiting devices that are conducting, so as to vary in a reverse direction/negative correlation with the voltage that the n LED arrays divide in the main loop/bypass loop.

In the present application, the concept of the threshold such as the turn-on threshold, the full brightness threshold, etc. can be understood in a plurality of angles, and each understanding is not necessary for the embodiments in the present application, but only for a certain application scenario. For example, alternatively, at one of the angles, the related concepts may be understood as follows: the voltage experienced by the LED array, or the turn-on voltage drop of the LED array, may be considered as the turn-on threshold of the LED array, i.e. the minimum forward voltage capable of causing the LED array to emit light, or, since the product of the implementation may not configure the LED array to emit light only "and it is desirable to have sufficient forward turn-on voltage drop to generate sufficient light emission, since the voltage experienced by the LED array, or the turn-on voltage drop of the LED array has the" current-voltage curve "and" current-relative-brightness curve "shown in fig. 1, the voltage experienced by the LED array, or the turn-on voltage drop of the LED array may also be considered as: the voltage of the LED array that generates the luminous flux to satisfy the product requirement to be implemented, or the voltage to which the LED array is subjected, or the voltage drop of the LED array to be turned on, is between "the minimum forward voltage that enables the LED array to emit light" and "the voltage of the LED array that generates the luminous flux to satisfy the product requirement to be implemented". In addition, the LED array that is not turned on has no turn-on voltage drop or "sustained voltage" theoretically enough to drive it to emit light, but for convenience of description, it is assumed in the present specification that it has the same "sustained voltage" or "turn-on voltage drop". Current in the LED array, refers to: the current flowing in the LED array that is turned on in the corresponding loop is turned on, while the operating current is absent or negligible in the LED array that is not turned on. The power or total power of the n LED arrays, refers to: the power of the LED array that is turned on in the bypass/main loop is turned on, while the LED array that is not turned on has no operating power or power can be ignored. Further, for a lighting load or LED embodied in a commercial product, the photoelectric conversion parameter is substantially constant or substantially predictable, and therefore, it can be considered that: by controlling the (electrical) power of the LED array to remain constant, the luminous flux of the LEDs is indirectly controlled to remain substantially constant. For this reason, the description is omitted here or not. Optionally, in some embodiments, the voltage sustained by the LED array, or the conduction voltage drop of the LED array, may also be referred to as a conduction threshold, different numbers of LED arrays have different conduction thresholds, and the conduction threshold of all n series-connected LED arrays may be referred to as a full brightness threshold.

In addition, the turn-on threshold can also be understood from another point of view: the voltage value of the direct current power supply can make all or part of the n LED arrays be conducted and the luminous flux reach a preset value.

The predetermined value is the requirements of the product being implemented, typically a specified luminous flux value, for example 1000 lumens. From a third perspective, the turn-on threshold can also be understood as follows: the turn-on threshold is related to the LED array that the output dc voltage of the dc power supply can turn on/light up. If the DC voltage is below the turn-on threshold, fewer of the n LED arrays can be turned on. Alternatively, only the LED array group of "having the sum of lower turn-on voltage drops" of the n LED arrays can be turned on.

From a fourth perspective, the turn-on threshold can also be understood as follows: the turn-on threshold is related to the LED array that the output dc voltage of the dc power supply can turn on/light up. If the dc voltage is above this turn-on threshold, it is sufficient to turn on the first LED array group, and if the dc voltage is below this turn-on threshold, it is not sufficient to turn on the first LED array group, and may only turn on the second LED array group. The first LED array group has a higher sum of the conducting voltage drops than the second LED array group, or the first LED array group has a larger number of LED arrays than the second LED array group. If the first LED array group includes all n LED arrays in the lighting device, this turn-on threshold may also be referred to as a full brightness threshold. This means that: if the dc voltage is above the full bright threshold, it is sufficient to turn on all n LED arrays, and if the dc voltage is below the full bright threshold, only a portion of the n LED arrays can be turned on. Also optionally, the full brightness threshold in some embodiments may correspond to the first threshold in the control circuit, the lighting device.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: and the current in the LED array which is conducted in the n LED arrays is reduced along with the increase of the voltage borne by the pulsating direct current voltage/n LED arrays, or the current in the LED array which is conducted in the n LED arrays is increased along with the decrease of the voltage borne by the pulsating direct current voltage/n LED arrays.

Thus, the power to the n LED arrays is regulated to remain within a neighborhood of the first power value, which may be the range of power maintained by the first/main loop during operation, where the first power value is typically dictated by the requirements of the particular lighting implementation. Correspondingly, a first power value over the n LED arrays may result in a first luminous flux.

Optionally, in the control circuit in some embodiments, the control unit includes an electrical signal measurement unit, and is coupled to the control circuit (coupled to the main loop or the possible bypass circuit) to obtain a first electrical signal, where the first electrical signal reflects/represents the pulsating dc voltage or the conducting voltage drop of the n LED arrays, or has a positive/negative correlation with the pulsating dc voltage or the voltage borne by the n LED arrays. If the first electrical signal has a positive correlation with the voltage of the direct current power supply or the conduction voltage drop of the n LED arrays, the control unit is further configured to: 1) in response to the first electric signal being smaller than a first threshold, controlling at least one of the m switching units to conduct to establish a bypass; 2) and controlling all the m switch units to be turned off in response to the first electric signal being greater than or equal to the first threshold value. Alternatively, if the first electrical signal has a negative correlation with the voltage of the dc power supply or the turn-on voltage drop of the n LED arrays, the control unit is further configured to: in response to the first electric signal being larger than a first threshold, controlling at least one of the m switch units to conduct to establish a bypass; ii) controlling at least one of the m switching units to turn off in response to the first electrical signal being less than or equal to the first threshold value.

Optionally, in the control circuit in some embodiments, the control unit includes an electrical signal measurement unit, which is coupled to the control circuit (coupled to the main loop or the possible bypass circuit) to obtain a first electrical signal reflecting/positively correlating/negatively correlating the pulsating dc voltage or the on-voltage drop of the n LED arrays or the difference between the pulsating dc voltage and the on-voltage drop of the LED arrays. If there is a positive correlation between the first electrical signal and the voltage of the direct current power supply or the difference between the conduction voltage drop of the n LED arrays or the pulsating direct current voltage and the conduction voltage drop of the LED arrays, the control unit is further configured to: 1) in response to the first electric signal being smaller than a first threshold, controlling at least one of the M switch units to conduct to establish a bypass; 2) and controlling all the M switch units to be turned off in response to the first electric signal being greater than or equal to the first threshold value. Alternatively, if the first electrical signal has a negative correlation with the voltage of the dc power supply or the difference between the conduction voltage drop of the n LED arrays or the pulsating dc voltage and the conduction voltage drop of the LED arrays, the control unit is further configured to: in response to the first electric signal being larger than the first threshold, controlling at least one of the M switch units to conduct to establish a bypass; ii) controlling at least one of the M switching units to turn off in response to the first electrical signal being less than or equal to the first threshold value.

Alternatively, in some embodiments, the first electrical signal may be taken from both ends of a (derived from) dc power source, or obtained by a circuit coupled to the positive and negative polarity outputs of the dc power source.

Optionally, in the control circuit in some embodiments, in a state where at least one of the switching units is turned off, the first electrical signal may be acquired based on one or more circuit parameters in the control circuit. For example, the first electrical signal may be derived from at least one of a voltage across the current limiting device, a voltage at a control terminal of the current limiting device, and a current of the current limiting device. Optionally, in the control circuit in some embodiments, in a state where the at least one switching unit is turned on, the first electric signal is taken from at least one of a voltage across the current limiting device, a voltage at a control terminal of the current limiting device, and a current of the current limiting device. The control unit of the control circuit is configured to determine, by one or more circuit parameters: i) whether the dc voltage is sufficient to turn on all of the n LED arrays, or ii) the magnitude of the dc voltage relative to a first threshold. If the direct current voltage is larger than the first threshold value, all the n LED arrays can be conducted sufficiently, and if the direct current voltage is smaller than the first threshold value, only a part of the n LED arrays can be conducted. In particular, in the control circuit, a first electrical signal is generated based on one or more circuit parameters and compared with a first threshold value configured in the control unit.

Alternatively, in the control circuit in some embodiments, the first electrical signal may be taken from both ends of the at least one common ground switching unit.

Optionally, in the control circuit in some embodiments, the first threshold configured in the control circuit may correspond to one of: i) reflecting the value of the voltage sustained by the LED array with sufficient voltage/current/power to meet the required luminous flux when all the n LED arrays are turned on; ii) a voltage value of the dc power supply reflecting that the n LED arrays have sufficient voltage/current/power to meet the required luminous flux when all are turned on; iii) a value of the first electrical signal reflecting a luminous flux with sufficient voltage/current/power to meet the demand when all of the n LED arrays are turned on; iv) a full bright threshold.

Optionally, in the control circuit in some embodiments, the first threshold configured in the control circuit may correspond to one of: i) a value of the first electrical signal reflecting a minimum voltage of the dc power supply sufficient to turn on all of the n LED arrays, ii) a reference voltage value whose difference from the minimum voltage value is a constant positive value, iii) a voltage value of the dc power supply that allows the on-current/luminous flux of the n LED arrays to reach a predetermined value; iv) a minimum voltage of the dc power supply sufficient to turn on all of the n LED arrays, v) a value of a first electrical signal reflecting a voltage value of the dc power supply that causes luminous fluxes of the LEDs in the n LED arrays to reach a predetermined value; VI) a value of a first electrical signal reflecting a minimum voltage of the dc power supply when a luminous flux generated by the voltage/current/power across the n LED arrays reaches a predetermined value; VII) just enough dc voltage value to turn on all of the n LED arrays.

Optionally, when at least one of the n LED arrays is bypassed, the current flowing through the n LED arrays or the current flowing through the bypass loop/sub-loop is adjusted by the control unit to be larger than the current of the main loop when all the n LED arrays are turned on.

The control unit is further configured to: and adjusting the first bypass current in the at least one switched unit to be conducted to be larger than the current value flowing through the n LED arrays when the m switched units are all switched off, so that the product of the conduction voltage drop of the n LED arrays and the first bypass current is kept in the neighborhood of the first power value.

Optionally, in the control circuit or the driving/controlling method of any embodiment of the present application, x is 0, and the control unit is further configured to switch the m switching units to establish or cancel the bypass loop in response to a fluctuation of the first electric signal with respect to the first threshold. So that after a part of the n LED arrays is bypassed, the dc supply voltage is sufficient to turn on the other LED arrays.

Optionally, in the control circuit or the driving/controlling method of any embodiment of the present application, wherein m > x ≧ 1, m ≧ 2, the control unit is further configured to a) alternately turn off a plurality of the m switching units in response to the first electrical signal falling below a first threshold (e.g.: in the first period, the switch unit A is switched on, and the switch unit B is switched off; the switch unit B is switched on and the switch unit A is switched off in a second period; the switch unit a is turned on and the switch unit B is turned off in the third period) to alternately turn on the corresponding plurality of LED arrays; or b) in response to the first electrical signal falling below the first threshold, complementarily switching the on-state or the off-state of a plurality of switching cells including at least one of the x switching cells and at least one of the m-x switching cells, thereby establishing a plurality of alternating bypass loops. For example, when a first part of the switch units in the plurality of switch units are in an on state, a second part of the switch units are in an off state, and when the second part of the switch units are in the on state, the first part of the switch units are in the off state. The first partial switching unit or the second partial switching unit includes at least one of x switching units. Optionally, the alternating conduction or the rotational conduction has a first predetermined frequency.

In the control circuit or the driving circuit/control method according to any embodiment of the present application, different portions of the n LED arrays, such as the first subset (subset) and the second subset (subset), are alternately/alternately turned on in a low voltage interval (having a lower voltage and not enough to turn on all the n LED arrays, such as the first voltage interval) of the dc power supply, while generally, the low voltage interval cannot simultaneously turn on the LED arrays in the union/union (union) of the first subset and the second subset, optionally, the first subset and the second subset each have: when the LED array is positioned in the low-voltage interval, the direct-current power supply conducts the maximum number of the LED arrays in the n LED arrays. Alternatively, the number of LED arrays in the union of the first subset and the second subset is greater than the (e.g., maximum) number of LED arrays that the dc power supply can conduct in the low voltage interval. To this extent, the electric energy that DC power supply provided in the low-voltage interval releases for the light energy through more LED array, therefore also can bring bigger LED light emitting area, suppresses the low frequency stroboflash/scintillation to a certain extent.

Further optionally, the number of LED arrays in the first subset is the same as the number of LED arrays in the second subset, which results in that the above-mentioned light energy released by the larger number of LED arrays forms a relatively constant light emitting area, in other words, the n LED arrays generate a stable power/luminous flux with a visually constant light emitting area, and the low frequency stroboflash/flicker is suppressed to some extent.

Still further optionally, the union of the first subset and the second subset covers (cover) all n LED arrays, so that during a change from the normal voltage interval of the dc power supply to e.g. the first voltage interval having a lower voltage value, the total light emitting area of the n LED arrays may remain substantially unchanged, improving the lighting experience. In other words, the power of the n LEDs is kept substantially unchanged by combining with the current regulation means, and the n LED arrays always stably generate stable power/luminous flux with the maximum possible light emitting area, thereby further suppressing the low-frequency stroboflash/flicker.

Optionally, the LED arrays in the subsets that are alternately turned on, such as the first subset and the second subset, are not identical, and there may or may not be an intersection between the two.

Optionally, the LED arrays in the first and second subsets that are alternately turned on are different, and there is no intersection between the two.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: when the first electrical signal is less than the first threshold value, coordinating (coordinating) the currents in the plurality of switching cells being switched (or, in other words, the currents in the plurality of alternately operating bypass loops) such that the power of the n LED arrays remains substantially constant before and after switching, all within a neighborhood of the first power value.

Optionally, the control unit is further configured to: the current in the first part of switch units switched from on to off state and the current in the second part of switch units switched from off to on state are synchronously controlled to make the sum of the powers of all the LED arrays in the loop in which the first part of switch units and the second part of switch units are located substantially constant, or in other words, make the sum of the powers of the n LED arrays substantially constant, so as to control the luminous flux of the n LED arrays to be substantially constant or to be kept within a neighborhood of a first luminous flux predetermined value, for example within a neighborhood of ± 5% or even less of the first luminous flux predetermined value.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: the current in the plurality of alternating bypass loops is coordinated by the plurality of switching units such that the power of the LED arrays in the plurality of alternating bypass loops is each maintained within the vicinity of the first power value.

Optionally, in the control circuit in some embodiments, wherein the plurality of alternating bypass loops includes a first bypass loop and a second bypass loop, if the LED array in the n LED arrays located in the first bypass loop has a larger conduction voltage drop than the LED array in the second bypass loop, the current in the second bypass loop is adjusted to be larger than the current in the first bypass loop, so that the relative rate of change of the power between the LED array in the second bypass loop and the LED array in the first bypass loop is smaller than a first predetermined percentage, and the first predetermined percentage is a value smaller than 10%, 5%, or 2%.

Alternatively (alternatively), if the LED array conduction voltage drop in the first bypass loop is substantially equal to the LED array in the second bypass loop (e.g. the relative rate of change of the two during the switching process does not exceed a first predetermined percentage), the control unit is further configured to: adjusting the current in the second bypass loop to be substantially equal to the current in the first bypass loop (e.g., the relative rate of change of the two during the switching process does not exceed a first predetermined percentage) such that the relative rate of change of the power of the LED array in the second bypass loop and the LED array in the first bypass loop is less than a first predetermined percentage, the first predetermined percentage being a value less than 10%, 5%, or 2%; and

optionally, the number of LED arrays in the union of the LED arrays in the first bypass loop and the LED arrays in the second bypass loop is greater than the maximum number of n LED arrays that can be turned on by the dc power supply when the first electrical signal is smaller than the first threshold.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: when m > x ≧ 1, coordinating currents in the current limiting device and the plurality of switching units that are switched during fluctuation of the first electrical signal with respect to a first threshold value such that power of the n LED arrays remains within a neighborhood of the first power value in a state where the plurality of switching units are all turned off and at least partially turned on

Optionally, in the control circuit in some embodiments, the control unit is further configured to: when x is 0, coordinating the current in the current limiting device and the currents in the m switching units during fluctuations of the first electrical signal with respect to the first threshold value such that the power of the n LED arrays remains within a neighborhood of the first power value in a state where the m switching units are all off and at least partially on.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: during the transition when a plurality of switching units are switched,

i) synchronously controlling the current in a first part of switch units in the plurality of switch units to be reduced along with the increase of the current in a second part of switch units in the plurality of switch units, so that the power reduction of the LED arrays corresponding to the first part of switch units is compensated/offset by the power increase of the LED arrays corresponding to the second part of switch units; and the number of the first and second groups,

ii) synchronously controlling the current in a first part of the switch units in the plurality of switch units to increase along with the decrease of the current in a second part of the switch units in the plurality of switch units, so that the power decrease of the LED arrays corresponding to the second part of the switch units is compensated/offset by the power increase of the LED arrays corresponding to the first part of the switch units.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: during the transition in switching between the first bypass loop and the second bypass loop, i) synchronously controlling the current in the first bypass loop to decrease with increasing second bypass loop current, such that the power drop of the LED array in the first bypass loop is compensated/cancelled by the power increase of the LED array in the second bypass loop; and ii) synchronously controlling the current in the first bypass loop to increase as the current in the second bypass loop decreases such that the power drop of the LED array in the second bypass loop is compensated/offset by the power increase of the LED array in the first bypass loop.

Here, the current regulation during the switching process will be described by taking only the transition process of switching between the first bypass circuit and the second bypass circuit as an example. The current regulation means may be adapted to switch between any two or more loops in the control circuit, for example, between the main loop (or the first loop/series loop) and the bypass loop. In the control circuit in the related embodiments, the control unit is further configured to: during a transition in switching between the first loop and the bypass loop, i) synchronously controlling the current in the first loop to decrease as the bypass loop current increases such that the power drop of the LED array in the first loop is compensated/offset by the power increase of the LED array in the bypass loop; and ii) synchronously controlling the current in the first loop to increase as the current in the bypass loop decreases such that the power drop of the LED array in the bypass loop is compensated/offset by the power increase of the LED array in the first loop.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: and controlling the current in the first part of switch units to increase synchronously before the descending amplitude of the current in the second part of switch units relative to the current before the transition process begins exceeds a preset amplitude value in the transition process of switching conduction from the second part of switch units to the first part of switch units.

Optionally, in the control circuit in some embodiments, the control unit is further configured to: controlling the current in the second partial switch unit to increase synchronously before the falling amplitude of the current in the first partial switch unit relative to the current before the transition process begins exceeds a preset amplitude value in the transition process of switching on from the first partial switch unit to the second partial switch unit

Optionally, the preset amplitude is any value less than 5%.

Optionally, in the control circuit in some embodiments, the union of the LED arrays in each of the plurality of alternating bypass loops includes or includes all of the n LED arrays.

Optionally, in the control circuit in some embodiments, the union of the LED arrays that are alternately turned on includes all of the n LED arrays.

Optionally, in the control circuit in some embodiments, a union of the n-m LED arrays that are not bypassed and the LED arrays that are turned on alternately includes all the n LED arrays.

Optionally, in the control circuit in some embodiments, any one of the following three: i) an LED array turned on by each switching group of the plurality of switching cells being switched, ii) a union of the n-m LED arrays and the LED array turned on by each switching group of the plurality of switching cells being switched, or iii) an LED array in each of the plurality of alternating bypass loops, the LED array capable of being lit in the n LED arrays corresponding to a maximum or next largest number of outputs of the dc power supply. Among them, the plurality of switching units (sw1, sw2, sw3) being switched may be divided into a plurality of switching groups, for example: 3 switching groups sw1, sw2 and sw3 respectively establish 1 bypass loop when the switching groups are turned on, and when the control circuit controls n LED arrays, the n LED arrays have three bypasses. Or may be divided into two switch groups 1) sw1, 2) sw2 and sw 3. When the two groups of switches are conducted alternately, two bypass loops are established alternately.

The plurality of switch units or the m switch units are provided with a first switching group, and the n LED arrays can be lighted corresponding to the output of the largest number or next largest number of direct current power supplies.

Optionally, in the control circuit in some embodiments, the union of the LED arrays in each of the plurality of alternate bypass loops corresponds to all of the n LED arrays; alternatively, a plurality of alternating bypass loops, covering/including all n LED arrays.

Optionally, the switching unit is a field effect transistor, a triode, a transistor, a power transistor, or a MOS transistor.

Optionally, in the control circuit in some embodiments, m > 1, the control unit further includes a timing logic circuit in addition to the electrical signal measuring unit, an input end of the timing logic circuit is connected to the electrical signal measuring unit, and an output end of the timing logic circuit is connected to the control end of the switching unit and/or the control end of the current limiting device; generating at least two time signals complementary in time/waveform to control the at least two switching units/bypass loops to be alternately conducted in response to the first electric signal being lower than a first threshold value; or specifically, in response to the first electrical signal being lower than the first threshold, establishing a first bypass loop for a time corresponding to the first time signal, then canceling the first bypass loop, establishing a second bypass loop for a time corresponding to the second time signal, then canceling the second bypass loop, establishing the first bypass loop for a time corresponding to the first time signal, and thus alternately turning on the first bypass loop and the second bypass loop; or, when the time signal is greater than two, for example, three, in response to the first electrical signal being lower than the first threshold, establishing a first bypass loop for a time corresponding to the first time signal, then canceling the first bypass loop, establishing a second bypass loop for a time corresponding to the second time signal, then canceling the second bypass loop, establishing a third bypass loop for a time corresponding to the third time signal, then canceling the third bypass loop, establishing the first bypass loop for a time corresponding to the first time signal, and thus cyclically conducting the first bypass loop, the second bypass loop, and the third bypass loop.

Optionally, in the control unit in some embodiments, the timing logic circuit further includes: a timer (or other circuits with timing/time delay functions, such as an oscillator, a frequency generator, a clock generator, etc., which are not described in detail here) and at least one flip-flop. The electric signal measuring unit, the timer and the at least one trigger are sequentially connected; the electric signal measuring unit is configured to output a comparison signal according to the magnitude relation between the first electric signal and the first threshold; the timer responds to the comparison signal and reaches a preset timing threshold to generate at least one timing signal related to time, the output end of at least one trigger is respectively connected with the control end of at least one switch unit, responds to the at least one timing signal and outputs at least one time signal to control the on or off of the at least one switch unit.

Optionally, in the control unit in some embodiments, the comparison signal is input to the control terminal of the at least one switching unit, and the at least one switching unit is turned on or off in response to the input comparison signal.

Optionally, in the control unit in some embodiments, an output of the electrical signal measurement unit is coupled to an input terminal of a timing logic circuit, the timing logic circuit is coupled to control terminals of a first part of the m switch units and a second part of the m switch units, respectively, and the electrical signal measurement unit is configured to: if the first electric signal is detected to indicate that the output voltage of the direct current power supply is located in a first voltage interval, outputting a first comparison signal to the timing logic circuit, and the timing logic circuit is configured to: and in response to the comparison signal, controlling/coordinating the first part of switch units and the second part of switch units to be alternately/alternately turned on at a first preset frequency, so that corresponding first part of LED arrays and corresponding second part of LED arrays in the n LED arrays are alternately/alternately turned off. Or, it may also be understood that the timing logic is configured to: and in response to the comparison signal from the electric signal measurement unit, controlling/coordinating the first part of switch units and the second part of switch units to be alternately/alternately turned off at a first preset frequency so as to alternately/alternately turn on the corresponding first part of LED arrays and the corresponding second part of LED arrays.

Further optionally, the control unit may further comprise a flip-flop, and an output of the timer is connected to an input terminal of the flip-flop, i.e. indirectly coupled to a control terminal of the first part of the switching units and/or the second part of the switching units through the flip-flop, and controls/coordinates the two parts of the switching units.

A flip-flop is herein understood to be a term for a flip-flop circuit or device, such as an R-S flip-flop, a JK flip-flop, a D flip-flop, a T flip-flop, etc., or other circuits or devices that can perform the same function, such as other circuits or devices having logic for a set/reset function.

The first predetermined frequency, which is substantially equal in value to the frequency of the alternating/rotational conduction of the plurality of switching units and the corresponding plurality of bypass loops or the plurality of portions of the LED array controlled by the timer, can be set to any value of [0.5kHz,50kHz ], or any value of [0.5kHz,5kHz ], [5kHz,10kHz ], [20kHz,40kHz ], [60kHz,100kHz ], [100kHz,500kHz ], [10kHz,50kHz ] through configuration of circuit parameters of the timing logic circuit 06A, generally if the first predetermined frequency is located at [20kHz,50kHz ], for example 30kHz, the overall performance is good, for example, stroboflash is reduced to a large extent while the generated electromagnetic interference is also not too large. Here, the exemplary structures of the timer and the trigger in the pair of control units described above may also be applied to any other related embodiments of the present invention.

The first predetermined frequency, which may be set by configuration of circuit parameters of the timing logic circuit, is substantially equal in value to the frequency of the alternating/rotational conduction of the plurality of switching cells and the corresponding plurality of bypass loops or plurality of portions of the LED array controlled by the timing logic circuit. When the first predetermined frequency is set to be high, human eyes cannot easily or cannot sense, for example, stroboflash larger than 3125HZ can be considered safe so as to exempt deep inspection, alternation/rotation larger than audio frequency (about 20KHZ) can avoid generating noise which is heard by human ears and is caused by energy change, alternation/rotation larger than 40K can avoid interference on infrared equipment and the like, however, the frequency is high, the energy change generated by alternation/rotation conduction easily causes unacceptable electromagnetic interference, and a more precise design is relatively needed; in addition, since it is not easy to implement a large-capacity capacitor in the chip manufacturing process, the first predetermined frequency needs to be set in consideration of various factors. Generally speaking, if the first predetermined frequency is set at [4kHz,30kHz ], [50kHz,100kHz ], the overall performance is better, and the strobe frequency, the electromagnetic interference intensity, the manufacturability and other factors are considered.

Optionally, in the control circuit of some embodiments, the control unit further comprises a timing logic circuit. An output of the electrical signal measurement unit is coupled to an input of the timing logic circuit, respective control terminals of the plurality of switch units are respectively coupled to an output of the timing logic unit, the electrical signal measurement unit is configured to: and outputting a first comparison signal to the timing logic circuit in response to the first electrical signal being less than the first threshold. The timing logic circuit is configured to cyclically output a plurality of control signals complementary in time at a first predetermined frequency in response to the first comparison signal. The plurality of switch units are operable to be switched on alternately at a first predetermined frequency according to a plurality of control signals respectively; alternatively, a plurality of control signals complementary in time are generated in response to the first comparison signal at a first predetermined frequency cycle, and are alternately input to the control terminals of the plurality of switching units (respectively). Wherein the first electrical signal is positively correlated to the pulsating direct current voltage (or the difference between the pulsating direct current and the conduction voltage drop of the LED array).

Optionally, in the control circuit of some embodiments, the electrical signal measurement unit further comprises a second comparator. The second comparator is coupled to the one or more switching units through the signal processing unit, respectively, so as to adapt a second comparison signal output by the second comparator to the control terminal of the one or more switching units. The inputs of the second comparator are configured to the second electrical signal and the first threshold, respectively.

Further optionally, the electrical signal measurement unit further comprises an integration unit. The second comparator, the integration unit, the signal processing unit and the one or more switching units are connected in sequence, and the integration unit controls the on and off of the one or more switching units and the switching of the current regulation state through the signal processing unit. Gradual transitions of one or more switching units between different states can be achieved by means of the integration unit, thereby reducing stroboscopic effects. Optionally, in the control circuit of some embodiments, the electrical signal measurement unit further comprises a first comparator. The second comparator, the integrating unit, and the first comparator are connected in sequence, an output end of the first comparator is coupled to the control ends of the one or more switching units, for example, directly coupled to the control ends of the one or more switching units, or indirectly coupled to the control ends of the one or more switching units through the signal processing unit, and the control signals respectively directed to the one or more switching units and output by the first comparator are correspondingly transmitted to, or distributed to, the control ends of the plurality of switching units through the signal processing unit.

Optionally, in the control circuit of some embodiments, the signal processing unit further comprises a timing logic circuit. The first comparison signal generated by the electrical signal measurement unit is input to the timing logic circuit, the control terminals of the plurality of switch units are respectively coupled to the output of the timing logic unit, and the electrical signal measurement unit is configured to: in response to the first electrical signal being less than the first threshold, the first comparison signal is input to the timing logic circuit. The timing logic circuit is configured to cyclically output a plurality of control signals complementary in time at a first predetermined frequency in response to the first comparison signal. The plurality of switch units are operable to be switched on alternately at a first predetermined frequency according to a plurality of control signals respectively; alternatively, a plurality of control signals complementary in time are generated in response to the first comparison signal at a first predetermined frequency cycle, and are alternately input to the control terminals of the plurality of switching units (respectively). Wherein the first electrical signal is positively correlated to the pulsating direct current voltage (or the difference between the pulsating direct current and the conduction voltage drop of the LED array).

The second comparator is configured to receive the second electrical signal and the first threshold and output a comparison result to the integration unit.

The first comparator is configured to compare the first electrical signal with an output of the integrating unit.

Wherein the second electrical signal reflects: the minimum value of the pulsating direct current voltage, or the minimum value of the difference between the pulsating direct current voltage and the voltage endured by the LED array. The at least one electrical signal includes a first electrical signal and a second electrical signal. Alternatively, the first electrical signal may be an instantaneous value reflecting the pulsating dc voltage in real time, and the second electrical signal may be a minimum value reflecting only the pulsating dc voltage. The second electrical signal may be obtained (derived from) based on the first electrical signal.

Alternatively, in the control circuit of some embodiments, the input of the electrical signal measurement unit is coupled to the control circuit (at some location within or outside) to obtain a characteristic reflecting the pulsating direct current voltage, which may be at least one of i) a maximum value, ii) a minimum value, iii) an average value, or iiii) an effective value of the pulsating direct current voltage.

The output end of the electric signal measuring unit is coupled to the control ends of the m switching units. It is assumed that when the minimum value of the pulsating dc voltage is higher than the turn-on threshold, the pulsating dc voltage is sufficient to turn on p LED arrays of the n LED arrays in a full period, and at this time, there are y switch units of the m switch units which are controlled by the control unit to be kept on so as to allow p LED arrays of the (enable) n LED arrays to be turned on and lighted, if y is 0, it means that all m switch units are turned off and correspondingly all n LED arrays are lighted. The control unit is configured to: z of the m switch cells remain on for a full cycle of the pulsating direct current voltage in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the turn-on threshold.

In the control circuit of some embodiments, z of the m switch cells are held on such that a minimum value of the pulsating direct current voltage is sufficient to light q of the n LED arrays, q being a maximum number of LED arrays that the minimum value of the pulsating direct current voltage below a turn-on threshold can light up of the n LED arrays; or the conduction voltage drop of the q LED arrays connected in series is the largest current pulsating direct current voltage (in a whole period) in the combination of all the LED arrays which can be conducted in the n LED arrays. And y of the m switch cells are held conductive, q ≦ p ≦ n, optionally 0 ≦ y ≦ z ≦ m. Of course, in some cases, z may be larger than y depending on the connection positions of the floating switch and the common ground switch in the z switch cells in the control circuit. But z switching elements are turned on, which results in more LED arrays being bypassed to accommodate the decreasing minimum pulsating dc voltage than y switching elements are turned on.

Specifically, in some embodiments, it is assumed that x is 0, m is 1, n is 2, q is 1, p is 2, and y is 0. When the control circuit is used/applied to the n LED arrays, the positive polarity end of the pulsating direct current voltage, the first LED array of the n LED arrays, and the second LED array are connected in sequence to form a series circuit. The second switch unit of the m switch units is connected between the following 1) and 2): 1) the junction of the first LED array and the second LED array, and 2) the negative polarity end of the pulsating dc voltage. The second switching unit is thereby kept conductive for a full period of the pulsating direct voltage in response to at least one electrical signal indicating that the minimum value of the pulsating direct voltage falls below the conduction threshold, whereby the first LED array is individually illuminated and the second LED array is not illuminated during a full period of each pulsating period of the subsequent pulsating direct voltage. Depending on the circuit configuration, the value of the conduction voltage drop of each LED array, etc., the conduction threshold may comprise a plurality of specific values, for example, the full brightness threshold in the present embodiment. Here, the state of locking the first LED array to be independently lighted may last for at least one pulse period until the minimum value of the pulse voltage changes to a certain extent again within several pulse periods to cross some threshold values or voltage intervals of the conduction threshold values again.

Optionally, in the control circuit of another embodiment of the present invention, the electrical signal measuring unit is coupled to the control circuit to obtain at least one electrical signal reflecting the characteristics of the pulsating direct current voltage. The at least one electrical signal, for example, may include at least one of the second electrical signal and the first electrical signal. The second electric signal is used for reflecting the minimum value of the pulsating direct current voltage or the voltage value of the trough part, and the first electric signal is used for reflecting the pulsating direct current voltage or the voltage born by the n LED arrays.

The electric signal measuring units are respectively coupled to the control ends of one or more of the m switching units. The electrical signal measurement unit is configured to: whether the output voltage of the direct current power supply (for example, near the trough position of the output voltage) is enough to turn on the n LED arrays is judged according to at least one electric signal.

The control unit is configured to control the m switch units to keep the first part of the LED arrays on in a full period in at least one pulse period of the DC power supply in response to the at least one electrical signal reflecting that the output voltage of the DC power supply is insufficient to turn on the n LED arrays. Thus, during the at least one pulsing period, the portion of the LED array can be stably illuminated without strobing due to (low frequency) switching of the LED array.

Optionally, in the control circuit of an embodiment of the present invention, the electrical signal measurement unit further includes a second comparator, and output terminals of the second comparator are respectively coupled to the m switching units or some of the switching units; the second comparator is configured to receive the second electrical signal and the first threshold and output a comparison result for the two.

Optionally, in the control circuit according to an embodiment of the present invention, the dc power supply outputs a pulsating voltage, and the control unit is configured to, in response to the second electrical signal reflecting that the pulsating voltage, such as a valley portion, is insufficient to turn on the n LED arrays, gradually turn i) all of the n LEDs on into ii) the first portion of the LED arrays to be individually turned on through a plurality of pulsating cycles, wherein the gradual transition is smooth and gradual, the former gradually decreases (fade out), and the latter gradually increases (fade in) so that the luminous flux does not change abruptly.

Optionally, in the control circuit of an embodiment of the present invention, the electric signal measuring unit further includes an integrating unit connected between the second comparator and the m switching units. The integration unit is operable to control the average value of the currents in the first part of the LED arrays and the average value of the currents in the n LED arrays to increase and decrease cycle by cycle, respectively, in a plurality of ripple cycles according to the output of the second comparator. The change of the average value here may be embodied as a change of a duty ratio of a current in the first partial LED array or the n LED arrays. Under the action of the integration unit, after the conversion of a plurality of periods, the duty ratio of the state that the n LED arrays are all conducted in each pulse period gradually becomes zero, and the duty ratio of the state that the first part of the LED arrays are singly conducted in each pulse period is 100%, namely, the state occupies the whole time of each pulse period.

Optionally, in the control circuit of an embodiment of the present invention, the electric signal measurement unit further includes a first comparator connected between the integration unit and the m switching units. The control unit further comprises a signal processing unit which is respectively connected to the control ends of the m switch units and transmits signals from the first comparator and other circuit modules to the control ends of the m switch units, or transmits the signals to the control ends of the m switch units after further processing of the signal processing unit. The first comparator is configured to receive the first electrical signal and an output of the integration unit. The output of the integration unit may have a periodically varying amplitude, for example a sawtooth wave. Optionally, in the control circuit of an embodiment of the present invention, the signal processing unit includes a timing logic circuit connected between the control terminals of the m switching units and the output terminal of the first comparator, so that, if the output of the first comparator is high, which represents that the output of the integrating unit is greater than the first electric signal, the timing logic circuit cyclically outputs control signals complementary in time to at least part of the m switching units at a first predetermined frequency in response to the output of the high level. Thereby controlling the cyclic lighting of a plurality of parts of the n LED arrays. For example, within the control circuit, the timing logic circuit alternately sends temporally complementary control signals to i) the switching element corresponding to at least one of the first subset of LED arrays, and 2) the switching element corresponding to the second subset of the n LED arrays, to control the on-off state of the associated switching element.

Optionally, in the control circuit of some embodiments, the electrical signal measurement unit, the integration unit, and the m switching units are coupled in sequence, such that, by the integration unit and its cooperation with the electrical signal measurement unit and the switching units, the control unit is operable to: in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the conduction threshold, the first locking state in which the y switching cells are kept conductive is switched/transitioned step by step to a second locking state in which the z switching cells are kept conductive over a plurality of pulsation cycles.

Optionally, in the control circuit of some embodiments, wherein the transition/switchover/transition process from the first locking state to the second locking state further comprises coordinating a current in the z switch cells to a current in the y switch cells to change in reverse:

coordinating i) the current or the average value thereof in z switching cells to increase over a plurality of cycles, and ii) the current or the average value thereof in y switching cells to decrease synchronously over a plurality of ripple cycles.

Optionally, in the control circuit of some embodiments, coordinating the current in the z switch cells to vary inversely with the current in the y switch cells further comprises:

the duty cycle/amplitude of the conduction current in the y switching elements is adjusted in a decreasing manner cycle by cycle within a plurality of ripple cycles, and the duty cycle/amplitude of the conduction current in the z switching elements is adjusted in a decreasing manner cycle by cycle in synchronism.

Optionally, z switching cells, at least partially selected from x switching cells. Alternatively, the z switching cells include at least one of the x switching cells. Preferably, the z switch cells comprise at least one of the m-x switch cells in addition to the at least one floating switch.

In the control circuit of some embodiments, the electrical signal measurement unit, the timing logic circuit, and the m switch units are coupled in sequence such that, through the timing logic circuit and its cooperation with the electrical signal measurement unit and the m switch units, the control unit is operable to: in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the turn-on threshold, z switching cells are dynamically selected/configured among the m switching cells and turned on by the time-complementary control signals cyclically output by the timing logic circuit at the first predetermined frequency. So that the number of switching elements that are turned on at each instant remains z, although in total the number of switching elements acted on by the control signal that cycles at the first predetermined frequency is more than z. This makes it possible to turn on only q LED arrays at most due to the reduction of the pulsating dc voltage, but the number of LED arrays actually available for releasing luminous flux is larger than q, and if the voltage reduction is not so large and z switching units are appropriately configured, the n LED arrays can all keep releasing luminous flux to the outside, improving the lighting performance.

Specifically, in some embodiments, the n LED arrays driven by the control circuit further include a third LED array connected in series in a series circuit formed by the first LED array, the second LED array and the dc power supply. The m switching units further include a first switching unit. When the control circuit is applied to the first LED array, the second LED array and the third LED array in the series circuit, the first switching unit will correspond to the first LED array and be connected in parallel with the first LED array. Thus, in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the full bright threshold (e.g., insufficient to simultaneously turn on the first LED array and the second LED array, but one of them may be individually turned on), the first LED array and the second LED array are alternately illuminated at the first predetermined frequency by the time-complementary control signals alternately output by the timing logic circuit to the control terminals of the first LED array and the second LED array, respectively, at the first predetermined frequency. In addition, the third LED array is not bypassed by any switch unit, so that the LED array can be in a normally-on state.

It should be noted that the coupling between the timing logic circuit and the switch unit (or the control terminal thereof), the coupling between the integration unit and the switch unit (or the control terminal thereof), and the coupling between the plurality of modules/units/components in other embodiments are not limited to direct electrical connection/electrical coupling, and may also form coupling through other indirect connection means, and details are not described herein.

Here, the exemplary structures of the electric signal measuring unit, the timing logic circuit, the timer and the flip-flop in the pair of control units described above may also be applied to other related embodiments of the present invention.

Optionally, in the control circuit of some embodiments, wherein the control unit is further configured to: i) switching between the series circuit and the plurality of bypass circuits is performed stepwise over successive plural pulse periods of the first electric signal in response to a change/rise in the lowest value of the first electric signal with respect to the first threshold; or ii) switching between the series loop and the plurality of bypass loops is done step by step through successive multiple pulsing cycles of the first electrical signal in response to a change in the lowest value of the first electrical signal across the first threshold.

Alternatively, the response of the lowest value of the first electrical signal to a change in the first threshold value may be delayed to form a different degree of "non-timely response" to ignore abrupt changes in electrical energy.

Optionally, in the control circuit of some embodiments, the control unit is further configured to: A) gradually adjusting, by a plurality of pulsation periods, the relative ratio of i) the duration of the plurality of bypass loops switched on to ii) the duration of the series loop in switching between the series loop and the plurality of bypass loops switched on; or B) gradually adjusting the duty ratio/value/average value of a) the currents in the plurality of bypass loops which are alternately conducted and B) the currents in the series loop in each pulse period in the switching between the series loop and the plurality of bypass loops which are alternately conducted.

Optionally, in the control circuit of some embodiments, wherein the first electrical signal is positively correlated with the pulsating direct current voltage; and the control unit is further configured to: switching on the series circuit at or near a maximum value of the first electrical signal over a plurality of pulse periods; when the serial loop is cut off, the plurality of bypass loops are switched on in turn; wherein i) the current in the series loop is complementary in time domain or pulse shape to ii) the current in the plurality of bypass loops.

Optionally, in the control circuit of some embodiments, the control unit is further configured to:

i) coordinating the decreasing of the duty ratio/value/average value of the current in the bypass loops in each of the plurality of pulse periods, and synchronously, the increasing of the duty ratio/value/average value of the current in the series loop in each of the plurality of pulse periods; or

ii) coordinating the increasing duty cycle/value/average value of the currents in the plurality of bypass loops in each of the plurality of ripple periods, and synchronously, the decreasing duty cycle/value/average value of the currents in the series loop in each of the plurality of ripple periods; or

iii) coordinating the decreasing duty cycle/average/amplitude of the current pulses in the plurality of bypass loops with the increasing duty cycle/average/amplitude of the current pulses in the series loop synchronously over a plurality of ripple periods; or

iiii) coordinating the duty cycle/average/amplitude of the current pulses in the plurality of bypass loops to increase and, synchronously, the duty cycle/average/amplitude of the current pulses in the series loop to decrease over a plurality of ripple cycles.

Optionally, in the control circuit of some embodiments, the LED arrays in the plurality of bypass loops have or do not have an intersection and have the same conduction voltage drop.

Optionally, in the control circuit of some embodiments, the plurality of bypass loops are respectively configured to have the maximum number or the next largest number of the pulsating direct-current voltages corresponding to the lowest value of the first electrical signal that can be conducted in the n LED arrays. The LED arrays in the bypass loops which are conducted alternately are combined to cover n or n-1 LED arrays, wherein the plurality of pulse cycles comprise any number of pulse cycles in the range of 3-1000, or the plurality of pulse cycles lasts for 1 ms-1000 ms.

Optionally, in the control circuit of some embodiments, the control unit further includes: a timer and an integration unit coupled to each other; the control unit is further configured to: a) adjusting, by the integration unit, the full brightness threshold to increment/decrement over a plurality of pulsing periods based at least in part on the timing signal from the timer; and, b) triggering a switch between the series loop and the plurality of bypass loops based at least in part on the increasing/decreasing full bright threshold.

Optionally, in the control circuit of some embodiments, the control unit further includes a first comparator coupled to the integration unit; the first comparator triggers, in accordance with the input of the integration unit and the first electric signal, i) switching between the series circuit and the plurality of bypass circuits, or, ii) turning on or off of the m-x switching units and the current limiting device.

Optionally, in the control circuit of some embodiments, the control unit is further configured to: 1) in the switching between the series circuit and the plurality of alternately conducting bypass circuits, the relative ratio of i) the duration of the plurality of alternately conducting bypass circuits to ii) the duration of the series circuit is gradually adjusted by a plurality of pulsation periods. Alternatively, the control unit is further configured to: 2) in switching between the series circuit and the alternately conducting multiple bypass circuits, the duty ratio/value/average value of a) the current in the alternately conducting multiple bypass circuits and b) the current in the series circuit in each pulse period is gradually adjusted.

Optionally, in the control circuit of some embodiments, wherein the control unit is further configured to: the switching between the series circuit and the bypass circuit is performed stepwise during successive periods of a plurality of pulses of the first electrical signal in response to fluctuations/rises of the lowest value of the first electrical signal relative to the first threshold value. Alternatively, the control unit is further configured to: switching between the series circuit and the bypass circuit is done step by step through successive multiple pulsing cycles of the first electrical signal in response to a change in the lowest value of the first electrical signal across the first threshold.

Optionally, in the control circuit of some embodiments, the control unit is further configured to: in the switching between the series circuit and the bypass circuit, the relative proportions of i) the duration of the bypass circuit switched on by turns and ii) the duration of the series circuit are gradually adjusted by a plurality of pulsation cycles. Alternatively, the control unit is further configured to: in the switching between the series circuit and the alternately conducting bypass circuit, the duty cycle/value/average value of a) the current in the alternately conducting bypass circuit and b) the current in the series circuit in each pulse period is gradually adjusted.

Optionally, in the control circuit of some embodiments, the first electrical signal is positively correlated with the pulsating direct current voltage; and the control unit is further configured to: switching on the series circuit at or near a maximum value of the first electrical signal over a plurality of pulse periods; when the series loop is cut off, the bypass loop is conducted; wherein i) the current in the series loop is complementary in time domain or pulse shape to ii) the current in the bypass loop.

i) coordinating the decreasing of the duty ratio/value/average value of the current in the bypass loop in each of the plurality of pulsation cycles, and synchronously, the increasing of the duty ratio/value/average value of the current in the series loop in each of the plurality of pulsation cycles; or

ii) coordinating the duty cycle/value/average value of the current in the bypass loop to increase in each of the plurality of ripple periods, and synchronously, the duty cycle/value/average value of the current in the series loop to decrease in each of the plurality of ripple periods; or

iii) coordinating the decreasing duty cycle/average/amplitude of the current pulses in the bypass loop with the increasing duty cycle/average/amplitude of the current pulses in the series loop in synchronism over a plurality of ripple cycles; or

iiii) coordinating the duty cycle/average/amplitude of the current pulses in the bypass loop to increase and, synchronously, the duty cycle/average/amplitude of the current pulses in the series loop to decrease over a plurality of ripple cycles.

Optionally, in the control circuit of some embodiments, the bypass loop is configured to have the maximum number or the next largest number of the n LED arrays that the pulsating dc voltage corresponding to the lowest value of the first electrical signal can conduct.

In an embodiment of the present invention, there is also provided a lighting device, including the control circuit of any of the embodiments herein, which may be integrated as a chip or an integrated circuit; and, also includes n LED arrays coupled peripherally to the chip or integrated circuit.

Optionally, the lighting device in some embodiments further includes a first resistor connected to the first switch unit and the bypass circuit/loop thereof through the current programming interface.

Optionally, the lighting device in some embodiments further comprises a dc power supply, which includes a rectifying circuit configured to receive input power, such as mains or other ac power, and rectify the input power for output to the n LED arrays.

Optionally, the electric signal measuring unit includes a voltage detecting circuit connected in parallel to an output of the rectifying circuit or the n LED arrays to detect the first electric signal by a corresponding voltage signal; alternatively, the electrical signal measuring unit is connected in series to at least part of the n LED arrays and/or the m switching units or current limiting devices to detect the first electrical signal by the corresponding current signal.

Alternatively, when the current of the LED arrays in the bypass loop is adjusted by the linear current source/switch unit in the bypass loop, the current can be adjusted in an opposite direction or in a negative correlation with the conduction voltage drop of the n LED arrays in the bypass loop, that is, the current value in the bypass loop is increased as the conduction voltage drop of the n LED arrays is reduced, so as to maintain the power of the LED arrays in the bypass loop, or the light output/luminous flux is substantially constant, in other words, the reduction of the power, light output/luminous flux of the n LED arrays caused by the voltage drop of the dc power supply is substantially compensated by adjusting the current of the n LED arrays.

Optionally, in the lighting apparatus in some embodiments, at least one of the m switching units and/or the current limiting device is configured as part of the voltage detection circuit.

Optionally, in some embodiments of the lighting device, the output terminal of the dc power source is connected to the electrolytic capacitor, and may store electric energy to some extent, for example, the value may be: several muF to several tens of muF. If the common ground switch unit and the floating ground switch unit are reconfigured appropriately, and the current regulation method is adopted, even in the limit situation of the voltage zero crossing point of the external direct current power supply (such as commercial power), all the LED groups are generally not completely extinguished, so that the stroboscopic phenomenon is reduced to a greater extent.

Optionally, in the lighting device in some embodiments, n ≧ 2, conduction voltage drops of at least two of the n LED arrays are the same, and the at least two LED arrays can be turned on by a corresponding switch unit of the m switch units in a rotating/rotating (poling) manner.

Optionally, in the lighting device in some embodiments, at least a part of the n-m LED arrays not coupled with the m switching units are connected in series before/upstream of the m LED arrays in the current direction. That is, when m is smaller than N, the switch unit and the LED array are respectively NPN or N-type, and some LEDs of the N LED arrays that cannot be bypassed by the m switches are connected in series in the (main) loop at a position closer to the positive polarity output terminal of the power supply, and therefore, the LEDs cannot be bypassed, and therefore, the LEDs are generally in a normally bright state, and the energy conversion efficiency of the whole loop can be improved. Additionally, in some embodiments, the switching unit or current limiting device may be operable to regulate current flowing therethrough, or may also be referred to as a current source.

Optionally, in the lighting device in some embodiments, the LED arrays that can be bypassed by the first partial switch unit and the LED arrays that can be bypassed by the second partial switch unit have the same conduction voltage drop. Correspondingly, during the switching process of the first part of switch units and the second part of switch units, the currents of the two bypasses can keep the same value, namely, the power of the lighting device can be kept unchanged. This does not generate noise due to a large adjustment of the current during switching, reducing the design requirements for the drive circuit.

Optionally, in some embodiments, the lighting device further comprises a switch unit coupled to the dc power supply, wherein the switch unit is configured to couple the m switch units to the n-m LED arrays.

Optionally, in some embodiments of the lighting device, the n-m LED arrays are located between the dc power source and the m-x switching units in a series circuit.

In an embodiment of the present invention, there is also provided a control method for an LED array for driving n LED arrays supplied with a dc power, including:

selectively bypassing the n LED arrays to accommodate the dc power supply when the dc power supply is low enough to not turn on the n LED arrays; wherein the selective bypass may establish at least one bypass loop for at least part of the n LED arrays.

When the dc power supply is sufficient to turn on the n LED arrays, selective bypassing of the n LED arrays is eliminated to establish a first loop comprising the dc power supply and all of the n LED arrays.

Optionally, the step of selectively bypassing at least one of the n LED arrays to accommodate the dc power supply further comprises at least one of the following steps a), B):

A) a bypass is established for a first subset of the n LED arrays respectively across each of the first subset of LED arrays.

B) And establishing a bypass connected across the second part of the LED arrays in the n LED arrays so as to integrally bypass the second part of the LED arrays to loop back the direct current power supply.

Alternatively, the step of selectively bypassing the n LED arrays to accommodate the dc power supply may further comprise at least one of the following steps a), b):

a) each of a first subset of the n LED arrays is bypassed separately.

b) A second portion of the LED arrays located on one side of the n LED arrays in series are entirely bypassed to allow the other ones of the n LED arrays except the second portion of the LED arrays to establish a closed loop with the DC power supply.

Wherein the at least one bypass loop includes two types of bypass loops: a first type bypass circuit and a second type bypass circuit. The bypass loop for bypassing the first part of the LED array is of a first type, or is referred to as a floating loop. Optionally, the bypass loop for bypassing the second part of the LED array belongs to a second type bypass loop, or is called a common ground loop.

Optionally, the method for controlling an LED array of some embodiments further includes the steps of: the current flowing through at least part of the n LED arrays is coordinated, e.g. by a current source in at least one bypass loop, such that the power value of the n LED arrays remains in the neighborhood of the first power value. The neighborhood of the first power value is also the power range that the first loop/main loop maintains during operation, so that the main loop and the bypass loop switch over each other without substantially affecting the power or luminous flux of the LED array.

Here, it should be understood that: the luminous flux of the LED and the power of the LED have strong correlation, and the luminous flux output of the n LED arrays is controlled to be basically constant by controlling the power of the LED to be basically constant.

Correspondingly, in the control method of the LED array of some embodiments, the method may further include the steps of:

the power of the n LED arrays within the neighborhood of the first power value is converted into luminous flux/lumens emitted by the n LED arrays within the neighborhood of the first luminous flux value.

Alternatively, the neighborhood of the first luminous flux, the neighborhood of the first power value, may be set relatively small, e.g. within ± 5% or 2% or even less of a certain normally operating power value/lumen value of the LED array, thereby achieving a certain degree of constant power, constant lumen.

Optionally, in the control method of an LED array of some embodiments, the step of coordinating currents further includes: the current of the first loop and the current in the at least one bypass loop formed by the selectively bypassed LED arrays are adjusted in association or in coordination such that the power of each of the n LED arrays is maintained at a first power value in the vicinity of the first power value during the establishment of the first loop and the at least one bypass loop.

Optionally, in the LED array control method of some embodiments, the dc power supply outputs a pulsating dc voltage, and the step of regulating the current further includes at least one of the following three steps:

i) and adjusting the current in the first loop to be in negative correlation change with the pulsating direct current voltage or the average value of the pulsating direct current voltage.

ii) the current regulating each of the at least one bypass loop and the conducting voltage drop of the LED array in the bypass loop are varied inversely/inversely proportionally.

iii) if at least one of the n LED arrays is bypassed, regulating the current flowing through the bypass loop to be larger than the current in the first loop when the n LED arrays are all on.

Optionally, the method for controlling an LED array of some embodiments further includes:

S-1) switching between the first loop and the at least one bypass loop in response to a voltage of the DC power source fluctuating around a full bright threshold, or as an output voltage of the DC power source fluctuates around a full bright threshold.

S-2) coordinating the current of the first loop and the current of the at least one bypass loop such that the power of the n LED arrays remains within a neighborhood of the first power value.

Optionally, the step S-2) further comprises:

s-2-1) responding to the first loop switching to the first type bypass loop, adjusting the current in the first type bypass loop to be larger than the current of the first loop, so that the power of the n LED arrays is kept in the neighborhood of the first power value before and after (or including) the switching process from the first loop to the first type bypass loop; wherein the bypass loop of the first type corresponds to the first part of the LED array or is used to bypass the first part of the LED array in a first manner; or

S-2-2) in response to the first loop switching to the second-type bypass loop, adjusting a current in the second-type bypass loop to be greater than a current of the first loop, such that a power of the n LED arrays remains within a neighborhood of the first power value before, after (or also including during, e.g., a transition in switching) a switching process of the first loop to the second-type bypass loop; wherein the second type bypass loop corresponds to the second part of the LED array or is for bypassing the second part of the LED array in a second manner; or

S-2-3) in response to the first loop switching to the third type bypass loop, adjusting the current in the third type bypass loop to be larger than the current of the first loop, so that the power of the n LED arrays is kept within the neighborhood of the first power value before, after (or during the switching process, such as the transition process of switching) the first loop to the third type bypass loop; wherein the third type bypass loop corresponds to the first part of the LED array and the second part of the LED array, or is used for synchronously bypassing the first part of the LED array and the second part of the LED array in a third way.

Optionally, the first partial LED array and the second partial LED array may not intersect with each other, or may intersect with each other.

The step S-1) further comprises the following steps:

and in response to the voltage of the direct current power supply being lower than a full lighting threshold, turning on at least one bypass loop to light the largest or next-largest number of the n LED arrays that the voltage of the direct current power supply can light. This allows a smaller number of LED arrays to be extinguished while maximizing the use of the voltage of the dc power supply.

Optionally, the method for controlling the LED array of some embodiments further comprises one of the following two steps:

I) and in response to the first loop being switched to one of the first type bypass loop, the second type bypass loop or the third type bypass loop, at least two of the first type bypass loop, the second type bypass loop and the third type bypass loop are conducted alternately. Or

II) when the voltage of the direct current power supply is lower than a full-bright threshold value, at least two of the first type bypass loop, the second type bypass loop and the third type bypass loop are conducted alternately.

Optionally, the control method of the LED array of some embodiments further comprises one or more of the following 3 steps:

1) in response to the first loop being switched to the first type bypass loop, alternately conducting the plurality of first type bypass loops; or

2) In response to the first loop switching to a second-type bypass loop, alternately conducting a plurality of second-type bypass loops; or

3) In response to the first loop being switched to the bypass loop of the third type, alternately switching on the plurality of bypass loops of the third type;

optionally, in the LED array control method of some embodiments, the step of alternately turning on further includes any one of the following steps: step i) coordinating (coordination) the currents of at least two of the bypass loops of the first type, of the second type, and of the third type, so that the power of the n LED arrays is kept in the neighborhood of the first power value during the alternating conduction; or, step ii) coordinates the currents of any one of a) a plurality of bypass loops of the first type, b) a plurality of bypass loops of the second type, and c) a plurality of bypass loops of the third type, so that the power of the n LED arrays is kept in the neighborhood of the first power value in the process of alternately conducting.

Optionally, in the LED array control method of some embodiments, the step of current coordination further includes:

step AA), during the switching from the bypass loop of the first type to the bypass loop of the second type, dynamically controlling the current in the bypass loop of the first type to decrease synchronously with the increase in the current in the bypass loop of the second type, so that the decrease in power in the bypass loop of the first type is compensated/counteracted by the increase in power in the bypass loop of the second type, and

step BB), during the switching from the second type bypass loop to the first type bypass loop, dynamically controlling the current in the second type bypass loop to decrease synchronously with the increase of the current in the first type bypass loop, so that the decrease of the power in the second type bypass loop is compensated/counteracted by the increase of the power in the first type bypass loop.

Step CC), during the switching from the first loop to one of the bypass loops, dynamically controlling the current in the bypass loop to increase synchronously with the decrease of the current in the first loop, such that the decrease of the power in the first loop is compensated/counteracted by the increase of the power in the bypass loop, and

step DD), during the switching from one bypass loop to the first loop, dynamically controlling the current in the bypass loop to decrease synchronously with the increase of the current in the first loop, so that the decrease of the power in the bypass loop is compensated/offset by the increase of the power in the first loop.

step EE) during the transition from the second-type bypass circuit to the first-type bypass circuit, before the current in the second-type bypass circuit drops by more than a preset amplitude value relative to the current before the transition starts, the current in the first-type bypass circuit is controlled to increase synchronously. And/or

And controlling the current in the second type bypass loop to increase synchronously before the descending amplitude of the current in the first type bypass loop relative to the current before the transition process starts exceeds a preset amplitude value in the transition process of switching from the first type bypass loop to the second type bypass loop.

Step FF) controls the synchronous increase of the current in the bypass loop before the descending amplitude of the current in the first loop relative to the current before the transition process starts exceeds a preset amplitude value in the transition process of switching from the first loop to the bypass loop. And/or

During a transition from a bypass loop to the first loop, the current in the bypass loop is controlled to decrease synchronously before the rise of the current in the first loop relative to the rise before the start of the transition exceeds a predetermined magnitude.

The preset amplitude may be any value between 0.1% and 5%, or any value in the adjacent range such as 3% to 10%, 0.01% to 3%, etc., and the amplitude here and some amplitudes and data ranges of other embodiments in the present application may be different according to different applications of the related method or the lighting device and the driving circuit, and are not limited to the data ranges/intervals that have been explicitly mentioned in the present application.

Optionally, in the LED array control method of some embodiments, the step of alternately turning on further includes:

alternately conducting the first type bypass loop and the second type bypass loop, thereby distributing the luminous flux of the n LED arrays on the maximum light-emitting area; or

The first-type bypass circuit and the second-type bypass circuit are alternately turned on to light all the n LED arrays in a single alternate turn-on period. Alternatively (optionally), the maximum area of the n LED arrays that can emit light can be understood as the normal light emitting area of the lighting device with the n LED arrays at rated power.

In an embodiment of the present invention, a method for controlling an LED array is further provided, including: at a driving circuit for driving n LED arrays powered by a direct current power supply, or at a lighting device having n LED arrays:

SA-1): when the voltage of the direct current power supply is higher than a full-bright threshold value and is enough to conduct the n LED arrays, driving the n LED arrays to be lightened;

SA-2): when the direct current power supply is lower than the full brightness threshold value and is not enough to conduct all the n LED arrays, only a part of the LED arrays (for example, a first part of the LED arrays) in the n LED arrays are driven to be lightened.

SA-1) when the voltage of the direct current power supply is higher than a full-bright threshold value and is enough to turn on the n LED arrays, driving the n LED arrays to be lightened;

SA-2) driving the n LED arrays to be partially lit when the voltage of the DC power supply is below a full-on threshold and insufficient to turn on the n LED arrays; alternatively, some and all of the n LED arrays are correspondingly/alternately illuminated in response to fluctuations in the voltage of the dc power supply relative to a full illumination threshold.

In an embodiment of the present invention, a method for controlling an LED array is further provided, including: at a driving circuit for driving n LED arrays in series, or at a lighting device having n LED arrays:

SA-1) supplying power to the n LED arrays through a direct current power supply;

SA-2) correspondingly lighting part of the n LED arrays and all the n LED arrays according to the voltage of the direct current power supply relative to the full lighting threshold; or, in response to the voltage of the direct current power supply being lower than/higher than the full-bright threshold, correspondingly/respectively lighting part of or all of the n LED arrays.

SA-1): detecting the voltage of the direct current power supply; the voltage of the direct current power supply higher than the full-brightness threshold value is enough to conduct the n LED arrays, and the voltage of the direct current power supply lower than the full-brightness threshold value is not enough to conduct all the n LED arrays;

SA-2) in response to/with a change in voltage of the dc power supply relative to a full bright threshold, respectively illuminate some or all of the n LED arrays.

Alternatively, the detection of the voltage of the direct current power supply may be performed by acquiring an electric signal proportional or positive/negative correlated to the voltage of the direct current power supply, without being limited to directly measuring the value of the voltage of the direct current power supply. For details, it is described in other related embodiments, and is not repeated herein.

Optionally, in the LED array control method according to some embodiments of the present invention, step SA-2) or the like may further include the sub-steps of:

SA-2-1) regulates the current through the n LED arrays substantially in reverse/negative dependence on the conduction voltage drop of the n LED arrays such that the power of the n LED arrays is maintained in the vicinity of the first power value. Here, the n LED arrays may be all turned on, or only some of the n LED arrays may be turned on.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2-1) or similar steps therein may further comprise the sub-steps of:

SA-2-1-1, the currents flowing i) when the n LED arrays are all switched on, and ii) when the partial LED arrays are switched on individually are coordinated such that the power of the n LED arrays that are all switched on and the power of the partial LED arrays that are switched on individually are both kept within the neighborhood of the first power value, in other words such that the power of the n LED arrays remains substantially constant during the period from the time when the n LED arrays are all switched on to the time when only some of the LEDs are switched on.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2-1-1) or similar steps therein may further comprise the sub-steps of:

in response to some of the LED arrays being individually illuminated, increasing the current in some of the LED arrays to greater than the current through which the n LED arrays are fully turned on to maintain the power of the n LED arrays in the vicinity of the first power value.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2-1-1) or similar steps therein may further include the sub-steps of:

I) when the voltage of the direct current power supply is higher than a full-bright threshold value, the current in the n LED arrays is increased along with the reduction of the voltage of the direct current power supply; reducing the current in the n LED arrays as the voltage of the dc power supply increases; and

II) when part of the LED arrays are conducted independently or the voltage of the direct current power supply is lower than a full brightness threshold value, increasing the current in the part of the LED arrays along with the reduction of the conduction voltage drop of the part of the LED arrays; reducing current in a portion of the LED array as a conduction voltage drop of the portion of the LED array increases;

thus, during the variation of the voltage of the direct current power supply, the power of the n LED arrays is kept within the neighborhood of the first power value.

The invention also provides a control method of the LED array, which comprises the following steps: at a driving circuit for driving an array of n mutually coupled LEDs powered by a dc power supply:

SA-1): in response to/if the output voltage of the DC power supply is greater than or equal to a turn-on threshold, driving to illuminate i) all of the n LED arrays, or ii) one of a first set of at least one partial LED array of the n LED arrays (one of a first at least one section of the n LED arrays);

SA-2): and in response to/if the output voltage of the direct current power supply is lower than the conduction threshold, only one of at least one partial LED array of a second group of the n LED arrays is driven to be lighted (one of a second LED least one section of the n LED arrays).

SA-1): in response to/if the output voltage of the dc power supply is greater than or equal to the turn-on threshold, driving to illuminate one of i) all n LED arrays, or ii) a first set of at least one partial LED array of the n LED arrays;

SA-2): and in response to/if the output voltage of the direct current power supply is lower than the conduction threshold, driving to light one of a second group of at least one partial LED array in the n LED arrays.

Optionally, in some embodiments, the number of LED arrays in each/any part of the first set of at least one partial LED arrays is greater than/equal to the number of LED arrays in each/any part of the second set of at least one partial LED arrays; and/or

The conducting voltage drop of the LED array in each/any part of the first group of at least one part of the LED arrays is larger than/equal to the conducting voltage drop of the LED array in each/any part of the second group of at least one part of the LED arrays.

Optionally, in some embodiments, one of the second set of at least one partial LED array has a maximum/next largest number or a maximum/next largest on-state voltage drop in the second set of at least one partial LED array.

Alternatively, in some embodiments, the turn-on threshold may take different specific values, such as threshold a (70 volts), threshold B (180 volts), and so on, depending on different operating states of the driving circuit, different configurations of the dc power supply, and so on. The turn-on threshold may comprise a full bright threshold (e.g., 215 volts).

The invention also provides a control method of the LED array, which comprises the following steps: at a drive circuit for driving n LED arrays powered by a dc power supply:

SA-1): driving to light p of the n LED arrays in response to/if the output voltage of the dc power supply is greater than or equal to a turn-on threshold;

SA-2): and responding to/if the output voltage of the direct current power supply is lower than a conduction threshold value, and driving and lighting q LED arrays in the n LED arrays, wherein p and q are integers, and p is more than or equal to q and is less than or equal to n.

Here, the n LED arrays have a certain association/cooperation relationship with each other in terms of light emission, and may be coupled with each other, for example, at least partially connected in series, at least partially connected in parallel, connected in series and parallel, and so on. The particular manner of connection between the LED arrays does not constitute a limitation on the method class embodiments of the present invention. The control method, the driving method and the like of the embodiment of the invention can be applied to any LED array and LED array group which are associated to emit light. The statements herein regarding the broad applicability of the method of this embodiment also apply to other method embodiments of the present invention, and further description thereof may be omitted here or may not be repeated here.

It should be understood that: in step SA-2) or the like, driving to light q LED arrays means: the other n-q of the n LED arrays are extinguished/bypassed. Wherein, p LED arrays, q LED arrays are a proper subset of n LED arrays. The p LED arrays and the q LED arrays are selected from the n LED arrays, and may be a fixed/determined LED array combination of the n LED arrays, or may be indeterminate and non-fixed, or p and q LED arrays dynamically selected/dynamically configured from the n LED arrays, or p or q LED arrays dynamically alternated among the n LED arrays. For example: n-3, q-2, the n LED arrays include [ a1, a2, A3], the q LED arrays may be [ a1, a2] at the previous time, and the q LED arrays may be [ a1, A3] at the next time. It can be understood that: only a fraction of the 3 LED arrays, i.e. 2 LEDs, are coupled to the control circuit at the same time during the output period of the dc power supply, and thus are sufficiently turned on by the dc power supply.

Here, it should be noted that: in the control method, the driving circuit or the control circuit according to some embodiments of the present invention, more diversified descriptions are provided from the perspective of driving to light q LED arrays, and certainly, the related control method, the driving circuit and the control circuit may also be described from the perspective of the other n-q extinguished LED arrays. It should be understood that the embodiments are included in the scope of the present invention and all such embodiments are considered to be described in the present application. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications. The q LED arrays driven to be turned on are turned off corresponding to the q floating switch units in the control circuit, or a certain number of the floating switch units and the common ground switch are switched to an off state in cooperation, and the n-q LED arrays turned off are turned on corresponding to the n-q floating switches in the control circuit, or a certain number of the floating switch units and the common ground switch are switched to an on state in cooperation. In some embodiments of the present application, although a detailed description is typically selected for a viewing angle at which the LED array is turned on/off, an operation manner and a control method of the corresponding switch unit are also (implicitly) disclosed. It should be understood that the embodiments are included in the scope of the present invention and all should be considered as described in the present application. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications.

Alternatively, in some embodiments, q < p; and/or the conducting voltage drop of the p LED arrays is larger than that of the q LED arrays.

Optionally, in some embodiments, wherein the q LED arrays have a maximum/next largest number of the n LED arrays that the output voltage of the dc power supply below the turn-on threshold can turn on.

Optionally, in some embodiments, wherein the p LED arrays have a maximum/next largest number that can be turned on in the n LED arrays when the output voltage of the dc power supply is above a turn-on threshold.

Optionally, in some embodiments, the turn-on threshold comprises a full-on threshold, and the output voltage of the dc power supply above the full-on threshold is sufficient to turn on all of the n LED arrays.

SA-1): in response to/if the output voltage of the dc power supply is greater than or equal to the turn-on threshold, drivingly illuminating i) all n LED arrays, or ii) a larger (larger) portion of the n LED arrays;

SA-2): and in response to/if the output voltage of the direct current power supply is lower than the conduction threshold, driving to light a smaller part of the n LED arrays.

SA-1): in response to/if the output voltage of the dc power supply is greater than or equal to the turn-on threshold, driving to illuminate i) all n LED arrays, or ii) a greater portion of the n LED arrays;

SA-2): and in response to/if the output voltage of the direct current power supply is lower than the conduction threshold value, only a smaller part of the n LED arrays is driven to be lighted.

The invention also provides a control method of the LED array, which comprises the following steps: at a drive circuit for driving a series of n LED arrays powered by a dc power supply:

SA-1): driving the n LED arrays to be fully illuminated in response to/if the output voltage of the dc power supply is above a full on threshold sufficient to turn on the n LED arrays;

SA-2): only a portion of the LED arrays driving the n LED arrays are illuminated in response to/if the output voltage of the dc power supply is below a full on threshold insufficient to turn on all of the n LED arrays.

Optionally, in some embodiments of the present invention, the magnitude of the output voltage of the dc power supply is variable, and such voltage variation may be periodic or aperiodic. Correspondingly, step SA-2) further comprises step SA-2-NO): and in response to the amplitude of the output voltage of the direct current power supply falling below a full brightness threshold value, only a part of the n LED arrays is driven to be lighted.

Optionally, in some embodiments of the present invention, the dc power supply outputs a rectified pulsating dc voltage, and step SA-2) further comprises step SA-2-NO): in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, driving only a portion of the n LED arrays to be illuminated in each of at least one pulsating cycle of the pulsating direct current voltage;

optionally, in some embodiments of the present invention, the q LED arrays, or the partial LED array is a first partial LED array of the n LED arrays, may be turned on/lit by a minimum voltage of the pulsating dc voltage in each pulsating period.

Optionally, in some embodiments of the present invention, the partial LED arrays are a plurality of partial LED arrays in the n LED arrays, and may be turned on/lit by the minimum voltage of the pulsating dc voltage, for example, in each pulsating cycle.

Optionally, in some embodiments of the present invention, the q LED arrays are part of the n LED arrays that are dynamically rotated, and may be turned on/lit by the minimum voltage of the pulsating direct current voltage (in each pulsating period).

Optionally, in some embodiments of the present invention, the first part of the LED arrays has the maximum number or the next largest number of the n LED arrays that the lowest voltage in the pulsating period of the pulsating dc voltage can conduct. Or, the plurality of partial LED arrays respectively have the maximum number or the next largest number of the n LED arrays which can be conducted by the lowest voltage in the pulse period of the pulse direct-current voltage.

Optionally, in some embodiments of the present invention, the number of LED arrays in the union of the plurality of partial LED arrays is n or n-1.

Optionally, some embodiments of the invention further comprise the step of: coordinating i) currents when the n LED arrays are all turned on, and ii) currents when the first portion of the LED arrays are individually turned on, such that a total power of the n LED arrays remains within a neighborhood of the first power value.

Optionally, in some embodiments of the invention, step SA-2-NO) further comprises step SA-2-NO-c): in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, actively controlling the plurality of partial LED arrays to be cycled on/on at a first predetermined frequency within or across one or more of the at least one pulsating cycle.

Here, it should be noted that: whether the pulsating direct current voltage falls below the full-bright threshold can be determined by measuring whether the trough portion/lowest value of the pulsating direct current voltage is less than the full-bright threshold. The specific detecting and determining means does not limit the present invention, for example, all the determination of the variation of the pulsating dc voltage with respect to the full-bright threshold value by the minimum value of the pulsating dc voltage within a certain period of time in the present invention may be instead to determine the variation of the pulsating dc voltage with respect to the full-bright threshold value directly or in real time by using the (instantaneous/current) value of the pulsating dc voltage, and similarly, the control method of some embodiments in the present invention is not only applicable to the pulsating voltage, but also applicable to other forms of variable voltage (with or without periodicity). Even if the voltage has a periodic variable voltage, the steps of step-by-step switching, high-frequency rotation, and the like between the LED arrays in different parts in the control method according to some embodiments of the present invention may be performed synchronously or asynchronously with the period of the output voltage of the dc power supply, which is also applicable to other embodiments of the present invention and will not be described again. The steps of other related embodiments may also be modified based on the determination result. In addition, a hysteresis/hysteresis method may be used to detect and determine whether a dc voltage such as a ripple voltage crosses a voltage range or a conduction threshold. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications.

Optionally, in some embodiments of the present invention, the output voltage of the dc power supply is variable, and if the output voltage crosses the turn-on threshold, it means that the output voltage goes from one voltage interval to another voltage interval, and the combinations of the LED arrays that can be turned on in the two voltage intervals are different, for example, the two different voltage intervals correspond to the first group of at least one LED array and the second group of at least one LED array respectively, the first group of at least one LED array includes the first group of LED arrays, and the second group of at least one LED array includes the second group of LED arrays. Correspondingly, step SA-2) further comprises step SA-2-NO-x): in response to the output voltage crossing/crossing the conduction threshold, transition from driving the first set of LED arrays to being illuminated to driving the second set of LED arrays to be illuminated. And the number of the second group to the LED arrays is less than or greater than that of the first group of the LED arrays, or the sum of the conduction voltage drops of the second group of the LED arrays is less than or greater than that of the first group of the LED arrays.

Optionally, the turn-on threshold is a full bright threshold. The output voltage falls below the full bright threshold and enters a first voltage interval, and in a subsequent period of time, the output voltage is below the full bright threshold and above the first bypass threshold, which may be referred to as the first voltage interval. The first group of LED arrays may include all of the n LED arrays, and the second group of LED arrays includes a part of the n LED arrays. Correspondingly, step SA-2-NO-x) further comprises step SA-2-NO):

In response to the output voltage falling below a full bright threshold, driving only a portion of the LED array to be illuminated; or

In response to the output voltage (of the dc power supply) falling within the first voltage interval, the driver LED array is individually illuminated for a duration in which the output voltage is within the first voltage interval.

Wherein, the minimum value of the output voltage of the dc power supply is sufficient to turn on the partial LED array, or the first voltage interval corresponds to the partial LED array, that is: the conduction voltage drop of the partial LED array is basically within the first voltage interval.

Optionally, in some embodiments of the present invention, the partial LED array is a first partial LED array of the n LED arrays, and the output voltage below a full lighting threshold is sufficient to turn on/light the first partial LED array; or the following steps: the voltage value in the first voltage interval is enough to turn on/light the first part of the LED array.

Optionally, in some embodiments of the present invention, the partial LED arrays are a plurality of partial LED arrays in the n LED arrays, and may be respectively turned on/lit by the output voltage within the first voltage interval, which is lower than the full-on threshold.

Optionally, in some embodiments of the invention, the first part of the LED array has: the maximum quantity or the next largest quantity of the output voltages with the voltage value or the output voltages below the full-bright threshold value in the first voltage interval can be conducted in the n LED arrays; or,

The plurality of partial LED arrays respectively have: and the maximum quantity or the next largest quantity of the output voltages with the voltage values or below the full-bright threshold value in the first voltage interval can be conducted in the n LED arrays.

Optionally, in some embodiments of the invention, step SA-2-NO) further comprises step SA-2-NO-c): in response to the output voltage falling below the full bright threshold, the plurality of partial LED arrays are controlled to be cycled on/on at a first predetermined frequency for a duration in which the output voltage is below the full bright threshold or within a first voltage interval.

Optionally, in some embodiments of the invention, step SA-2-NO) further comprises step SA-2-NO-c): in response to the output voltage falling below the full bright threshold or within the first voltage interval, controlling the plurality of portions of the n LED arrays to be cyclically turned on/on at a first predetermined frequency for a duration in which the output voltage is below the full bright threshold or within the first voltage interval.

Optionally, in some embodiments of the present invention, the plurality of partial LED arrays further comprises a first partial LED array and a second partial LED array, and the step SA-2-NO-c) further comprises the steps of:

In response to the output voltage falling below the full bright threshold or within the first voltage interval, the first partial LED array and the second partial LED array are controlled to be alternately or alternately turned on/lit at a first predetermined frequency for a duration in which the output voltage is below the full bright threshold or within the first voltage interval.

Optionally, the method of some embodiments further comprises the step SA-2-NO-cc): switching illumination between the first and second sets of LED arrays is performed over a first time period in response to a change in the output voltage of the DC power supply across the turn-on threshold.

Optionally, in some embodiments of the present invention, the turn-on threshold is a full bright threshold, and step SA-2-NO-cc) further comprises step SA-3-NO): in response to the change of the output voltage of the direct current power supply crossing the full-bright threshold value, switching and lighting between the n LED arrays and a part of the LED arrays is carried out through a first time period; or

In response to a change in the output voltage of the DC power supply across the full brightness threshold, gradually making each transition between the n LED arrays and the partial LED array over a first time period; or

Each transition between the n LED arrays and the partial LED array is completed step by step through a first time period in response to a change in the output voltage of the dc power supply across the full brightness threshold.

Wherein the first time period has a certain duration, for example 0.1 to 1 second/2 seconds.

Optionally, step SA-2-NO-cc) of the method of some embodiments further comprises step SA-3-NO-bb): during the transition between the first and second sets of LED arrays, the current in the first set of LED arrays (or the average thereof) and the current in the second set of LED arrays (or the average thereof) are coordinated to vary in reverse during a first period of time, for example: decreasing and increasing, respectively.

Optionally, in some embodiments of the present invention, the conduction threshold is a full bright threshold, and the step SA-3-NO-bb) or SA-3-NO) further comprises the step SA-3-NO-1):

in a first time period (or a first time period for short), coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively decreasing and increasing; or

Coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively increasing and decreasing in a first time period; or

And coordinating the current or the average value of the current in the n LED arrays which are all conducted with the current or the average value of the current in the partial LED arrays which are conducted separately, and respectively presenting an overall ascending trend and an overall descending trend in the first time period.

Optionally, the first time period is divided into a plurality of time slots, in each of which both the first group of the LED array and the second group of the at least one LED are turned on substantially complementarily in time, the step SA-3-NO-bb) of the method of some embodiments further comprising the step SA-3-NO-bb): the relative proportion of time that the first group of LED arrays are turned on in a plurality of time slots is coordinated to be decreased or increased respectively. Wherein the plurality of slots may be evenly divided or unevenly divided.

Optionally, in some embodiments of the present invention, the first group of LED arrays is all n LED arrays, and the second group of LED arrays is a part of the n LED arrays. Step SA-3-NO-bb) or step SA-3-NO) further comprises step SA-3-NO-1):

coordinating relative proportion of the working time of the n LED arrays which are all conducted and the working time of the partial LED arrays which are conducted separately in the conversion process between the n LED arrays and the partial LED arrays, and decreasing or increasing in a plurality of time slots; or

In a first time period, the duration of time for coordinating the n LED arrays to be fully conducted is increased/decreased time slot by time slot, and correspondingly, the duration of time for which the partial LED arrays are separately conducted is decreased/increased time slot by time slot;

Wherein the separately turned on partial LED array is the first partial LED array or each of a plurality of partial LED arrays turned on alternately.

Optionally, the step SA-3-NO-bb) further comprises the step SA-3-NO-bb-2) adjusting the duty cycle/magnitude of the current in the state where the first group of LED arrays are turned on slot by slot in a plurality of time slots in response to the output voltage falling below the turn-on threshold or within the first voltage interval, and synchronously adjusting the duty cycle/magnitude of the current in the state where the second group of LED arrays are turned on slot by slot in an incremental manner.

In response to the output voltage rising to within a voltage interval above the turn-on threshold or higher, the duty cycle/magnitude of the current in the state where the first group of LED arrays are turned on is adjusted incrementally from time slot to time slot over a plurality of time slots, and the duty cycle/magnitude of the current in the state where the second group of LED arrays are turned on is adjusted incrementally from time slot to time slot in synchronization.

Of course, it should be understood that: in each time slot, the first group of LED arrays and the second group of LED arrays are complementarily conducted, and when the second group of LED arrays is conducted, other LED arrays in the n LEDs are not conducted; while when the first group of LED arrays is turned on, the other LED arrays of the n LEDs will not be turned on.

Optionally, in some embodiments of the invention, step SA-3-NO-bb-2) or step SA-3-NO-1) further comprises any of the following sub-steps:

SA-3-NO-1a) in response to the output voltage falling below a full bright threshold, incrementally adjusting the duty cycle/magnitude of current in a state where the n LED arrays are fully turned on slot by slot over a plurality of time slots, and, synchronously, incrementally adjusting the duty cycle/magnitude of current in a state where the first portion of LED arrays are individually turned on slot by slot; or,

SA-3-NO-1b) in response to the output voltage rising above the full bright threshold, incrementally adjusting the duty cycle/magnitude of current in the fully on state of the n LED arrays by time slot over a plurality of time slots, and, synchronously, incrementally adjusting the duty cycle/magnitude of current in the individually on state of the first portion of LED arrays by time slot;

SA-3-NO-1c) in response to the output voltage falling below the full bright threshold, incrementally adjusting the duty cycle/magnitude of current in a fully on state of the n LED arrays from time slot to time slot over the plurality of time slots, and, synchronously, incrementally adjusting the duty cycle/magnitude of current during the alternating on state of the plurality of partial LED arrays from time slot to time slot; or,

SA-3-NO-1d) in response to the output voltage rising above the full bright threshold, incrementally adjusting the duty cycle/amplitude of current in the fully on state of the n LED arrays on a time slot by time slot basis over the plurality of time slots, and, synchronously, incrementally adjusting the duty cycle/amplitude of current during the alternate on state of the plurality of partial LED arrays on a time slot by time slot basis;

Wherein the plurality of time slots are adjacent to/correspond to at least one time slot in a time domain, and the current of the n LED arrays in the fully turned-on state and the current of the first partial LED array in the individually turned-on state are complementary in time/waveform, or the current of the n LED arrays in the fully turned-on state and the current of the plurality of partial LED arrays in the alternately turned-on state are complementary in time/waveform.

Optionally, in some embodiments of the invention, the first predetermined frequency at least partially provides a self-timer/frequency generator, step SA-3-NO-bb-2), step SA-3-NO-1a), SA-3-NO-1b), SA-3-NO-1c) or SA-3-NO-1d) further comprises the steps of:

the full bright threshold/turn-on threshold is adjusted incrementally/decrementally with the time slot of the output voltage by the integration unit according to the input from the timer.

Optionally, in some embodiments of the invention, the first period of time has a duration, for example, 0.05 seconds to 3 seconds. The first time period comprises any number of time slots from 5 to 1000.

Optionally, in some embodiments of the invention, step SA-2) further comprises step SA-2-FX): the plurality of partial LED arrays in the first group of LED arrays are controlled to alternately/alternately illuminate at a first predetermined frequency and/or the plurality of partial LED arrays in the second group of LED arrays are controlled to alternately/alternately illuminate at a first predetermined frequency.

Optionally, in some embodiments of the invention, step SA-2) further comprises step SA-2-F): the LED arrays of the plurality of portions of the n LED arrays are controlled to be alternately/alternately lit at a first predetermined frequency.

Optionally, the method in some embodiments of the invention further comprises the steps SA-2-F1): keeping at least one LED array of the n arrays other than the rotated plurality of partial LED arrays normally on.

Optionally, in some embodiments of the present invention, each of the plurality of partial LED arrays is configured to have a maximum number or a next largest number of the n LED arrays that the output voltage can be turned on;

I) a union of the plurality of partial LED arrays and at least one normally-on LED array, or, II) a union of the plurality of partial LED arrays, including n or n-1 of the n LED arrays; and the LED arrays of the plurality of portions have the same conduction voltage drop.

Optionally, the method of some embodiments of the invention, further comprises steps SA-2-F2X): in response to the change/rise of the output voltage relative to the conduction threshold, gradually performing switching lighting between the first group of LED arrays and the second group of LED arrays in a first time period; or

Switching between the first and second sets of LED arrays on is done step by step through a plurality of time slots within a first time period in response to a change in the output voltage across the turn-on threshold.

Optionally, steps SA-2-F2X) further comprise step SA-2-F25X): gradually adjusting, over a plurality of time slots, the relative proportion of i) the duration of time that the n LED arrays are fully illuminated, and ii) the duration of time that a plurality of partial LED arrays in the first group of LED arrays are alternately illuminated; or,

gradually adjusting, over a plurality of time slots, the relative ratio of i) the duration of the rotational illumination of the plurality of partial LED arrays in the first group of LED arrays to ii) the duration of the rotational illumination of the plurality of partial LED arrays in the second group of LED arrays; or

The relative proportions of i) the current (or average) used to drive the alternating illumination of the plurality of partial LED arrays in the first group of LED arrays and ii) the current (or average) used to drive the alternating illumination of the plurality of partial LED arrays in the second group of LED arrays are gradually adjusted over a plurality of time slots.

Wherein i) the current for alternately illuminating a plurality of partial LED arrays in the first group of LED arrays and ii) the current for alternately illuminating a plurality of partial LED arrays in the second group of LED arrays are complementary in time domain or pulse waveform.

Optionally, the turn-on threshold in the above embodiment is a full bright threshold. Correspondingly, steps SA-2-F2X) of the method of the related embodiment further include steps SA-2-F2): in response to the change/rise of the output voltage relative to the full-bright threshold, gradually performing switching lighting between the n LED arrays and the partial LED arrays in a first period; or

Switching between the n LED arrays and the partial LED array on is done step by step through a plurality of time slots in response to a change in the output voltage across the full bright threshold.

Optionally, in some embodiments of the invention, step SA-2-F25X) or step SA-2-F2) further comprises step SA-2-F25):

gradually adjusting, over a plurality of time slots, the relative ratio of i) the duration of time that a portion of the LED arrays are alternately illuminated to ii) the duration of time that the n LED arrays are fully illuminated; or,

the duty ratio/value/average value in each pulse period of a) the current for alternately lighting part of the LED arrays and b) the current for lighting all the n LED arrays is gradually adjusted. Wherein i) the currents for lighting a portion of the LED arrays are rotated, complementary to ii) the currents for lighting all n LED arrays, in the time domain or in a pulse waveform.

Optionally. Step SA-2-F25X) in the method of some embodiments further comprises at least one of the following sub-steps:

i) coordinating the decreasing of the duty ratio/value/average value of the current for driving the plurality of partial LED arrays in the first group of LED arrays to be alternately lighted in each of the plurality of time slots, and synchronously, the increasing of the duty ratio/value/average value of the current for driving the plurality of partial LED arrays in the second group of LED arrays to be alternately lighted in each of the plurality of time slots; or

ii) coordinating the increasing of the duty cycle/value/average value of the current for driving the alternating lighting of the plurality of partial LED arrays in the first group of LED arrays in the respective plurality of time slots, and synchronously, the decreasing of the duty cycle/value/average value of the current for driving the alternating lighting of the plurality of partial LED arrays in the second group of LED arrays in the respective plurality of time slots.

iii) coordinating (in a plurality of time slots) the decreasing pulse width/average/amplitude of the current pulses for alternately illuminating the plurality of partial LED arrays in the first group of LED arrays, synchronously with the increasing pulse width/average/amplitude of the current pulses for alternately illuminating the plurality of partial LED arrays in the second group of LED arrays; or

iiii) coordinating (in a plurality of time slots) the incremental pulse width/average/amplitude of the current pulses for alternately illuminating the plurality of partial LED arrays of the first group of LED arrays and, synchronously, the incremental pulse width/average/amplitude of the current pulses for alternately illuminating the plurality of partial LED arrays of the second group of LED arrays.

Optionally, in some embodiments of the present invention, the magnitude of the output voltage of the dc power supply is variable, and such voltage variation may be periodic or aperiodic. Correspondingly, step SA-2) further comprises step SA-2-NO): in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, only a portion of the n LED arrays are driven to be illuminated in each of at least one pulsating cycle of the pulsating direct current voltage.

Optionally, in some embodiments of the invention, step SA-2-NO) further comprises step SA-2-NO-c): in response to the pulsating direct current voltage falling below a full bright threshold, portions of the plurality of n LED arrays are actively controlled to be cycled on/on at a first predetermined frequency within each of the at least one pulsating cycle or across one or more of the at least one pulsating cycle.

Optionally, in some embodiments of the present invention, the plurality of partial LED arrays further comprises a first partial LED array and a second partial LED array, and the step SA-2-NO-c) further comprises the steps of: the first and second partial LED arrays are actively controlled to alternately or alternately conduct/illuminate at a first predetermined frequency within each of the at least one pulsing period or across one or more of the at least one pulsing period in response to the pulsating dc voltage falling below the full brightness threshold.

Optionally, some embodiments of the invention further comprise a step SA-3-NO), which step SA-3-NO) may be one of the following: 1) in response to the variation of the pulsating direct current voltage across the full brightness threshold, the conversion (or switching) lighting between the n LED arrays and the partial LED array is performed through a plurality of continuous pulsation periods. 2) Each transition between the n LED arrays and the partial LED array is made in steps over successive periods of the ripple in response to a change in the pulsating dc voltage across the full brightness threshold. 3) Each transition between the n LED arrays and the partial LED array is done step-wise through a succession of a plurality of pulsing periods in response to a change in the pulsating direct voltage across the full brightness threshold.

Optionally, in some embodiments of the present invention, step SA-3-NO) further comprises step SA-3-NO-1), and the step SA-3-NO-1) may be one of the following:

A) during the conversion process between the n LED arrays and the partial LED arrays, the average value of the current in the n LED arrays which are all conducted and the average value of the current in the partial LED arrays which are conducted separately are coordinated, and the average values are respectively decreased and increased in a plurality of pulse periods; or

B) Coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively increasing and decreasing in a plurality of pulse periods; or

C) And coordinating the current or the average value of the current in the n LED arrays which are all conducted with the current or the average value of the current in the partial LED arrays which are conducted separately, wherein the current or the average value of the current in the n LED arrays respectively shows an overall ascending trend and an overall descending trend in a plurality of pulse periods.

Optionally, in some embodiments of the invention, step SA-3-NO) further comprises step SA-3-NO-1):

a) coordinating relative proportions of on-time during which the n LED arrays are fully turned on and on-time during which the partial LED arrays are individually turned on during transitions between the n LED arrays and the partial LED arrays, the relative proportions being decreased or increased over a plurality of pulsing periods; or

b) In a plurality of pulse periods, coordinating that the duration of time that the n LED arrays are all turned on is increased/decreased cycle by cycle, and correspondingly, the duration of time that the partial LED arrays are individually turned on is decreased/increased cycle by cycle;

optionally, in some embodiments of the present invention, further comprising step SA-31-NO), the step may be one of: in response to a change in the lowest value of the pulsating direct current voltage across the full brightness threshold, during a transition between the n LED arrays and the individually conducting partial LED arrays,

A) coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively decreasing and increasing in a plurality of pulse periods; or

D) Coordinating the relative proportion of the on-time that the n LED arrays are fully turned on and the on-time that the separately turned on partial LED arrays are turned on, and decreasing or increasing in a plurality of pulse periods; or

E) In a plurality of pulsing periods, the duration of time during which the n LED arrays are coordinated to be fully turned on is incremented/decremented from period to period, and correspondingly, the duration of time during which the individually turned on partial LED arrays are turned on is decremented/incremented from period to period.

Optionally, in some embodiments of the invention, step SA-3-NO-1) or SA-31-NO) further comprises any one of the following four substeps:

SA-3-NO-1a) in response to the lowest value of the pulsating direct current voltage falling below a full brightness threshold, in a plurality of pulsating cycles, the duty ratio/amplitude of the current in the state that the n LED arrays are fully conducted is adjusted in a cycle-by-cycle decreasing manner, and the duty ratio/amplitude of the current in the state that the first part of the LED arrays are singly conducted is adjusted in a synchronous cycle-by-cycle increasing manner; or,

SA-3-NO-1b) in response to the lowest value of the pulsating direct current voltage rising above a full brightness threshold, in a plurality of pulsating cycles, the duty ratio/amplitude of the current in the state that the n LED arrays are fully conducted is adjusted in a cycle-by-cycle incremental manner, and the duty ratio/amplitude of the current in the state that the first part of the LED arrays are singly conducted is adjusted in a synchronous cycle-by-cycle incremental manner;

SA-3-NO-1c) in response to the lowest value of the pulsating direct current voltage falling below a full brightness threshold, in a plurality of pulsating periods, the duty ratio/amplitude of the current in the state that the n LED arrays are fully conducted is adjusted in a cycle-by-cycle decreasing manner, and the duty ratio/amplitude of the current in the process that the plurality of partial LED arrays are conducted alternately is adjusted in a synchronous cycle-by-cycle increasing manner; or,

SA-3-NO-1d) in response to the lowest value of the pulsating direct current voltage rising above a full brightness threshold, in a plurality of pulsating periods, the duty ratio/amplitude of the current in the state that the n LED arrays are fully conducted is adjusted in a cycle-by-cycle incremental manner, and the duty ratio/amplitude of the current in the process that the plurality of partial LED arrays are conducted alternately is adjusted in a synchronous cycle-by-cycle incremental manner;

in a local short period of time, for example, in a conversion process from "n LED arrays are all turned on" to "part of the LED arrays are turned on individually in at least one pulse cycle", a plurality of pulse cycles occupied by the conversion process (or referred to as a switching process) may be regarded as being located before the corresponding at least one pulse cycle in the time domain, and in a conversion process from "part of the LED arrays are turned on individually in at least one pulse cycle" to "n LED arrays are all turned on", a plurality of pulse cycles occupied by the conversion process may be regarded as being located after the corresponding at least one pulse cycle in the time domain. Whereas in a wider viewing angle i) a plurality of pulsating periods for switching the operation between the n LED arrays and the partial LED arrays, and ii) at least one pulsating period for keeping the partial LED arrays "locked"/operated individually, can be seen as occurring staggered in the time domain, e.g. in a one-to-one correspondence according to pulsating dc voltage variations, or in a one-to-many relationship. The current in the fully-on state of the n LED arrays and the current in the individually-on state of the (first) partial LED arrays are complementary in time/waveform, or the current in the fully-on state of the n LED arrays and the current in the process of the plurality of partial LED arrays being turned on alternately are complementary in time/waveform. Note that in this application, the text in parentheses or the text in parentheses is understood as optional text.

Optionally, in some embodiments of the present invention, the dc power supply outputs a rectified pulsating dc voltage, and step SA-2) further comprises step SA-2-NO):

in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, only a portion of the n LED arrays are driven to be illuminated in each of at least one pulsating cycle of the pulsating direct current voltage. Or,

in response to the lowest value of the pulsating direct current voltage falling below a full lighting threshold, actively controlling a portion of the n LED arrays to be individually lit during each of at least one pulsating cycle of the pulsating direct current voltage.

Wherein the partial LED arrays can definitely correspond to at least one LED array with the number less than or equal to n-1. From another perspective, partial LED arrays can also be understood as at least one LED array, with a fixed/locked number less than or equal to n-1, that is kept running during the corresponding voltage cycle and is no longer switched. That is, the n LED arrays are no longer passively (fully) voltage-adapted to the variation of the pulsating dc voltage by switching to other LED arrays or to all of the n LED arrays in order to optimize the power efficiency of the n LED arrays. At a certain time, the number of the LED arrays in a part of the LED arrays is less than or equal to n-1, but at different times, active rotation may be performed at a certain frequency (generally, a higher frequency is set to reduce low-frequency stroboscopic) under the active control of the control unit of the driving circuit, which may refer to the description of the related embodiments and is not repeated here. That is, even if some portion of the pulsating dc voltage is sufficient to turn on all n LED arrays, all n LED arrays are not controlled to be turned on.

Alternatively, it should be understood that: a first bypass threshold, or a second bypass threshold, may also be provided. When the pulsating direct current voltage drops from between the full lighting threshold and the first bypass threshold and is stabilized between the first bypass threshold and the second bypass threshold within a period of time, the LED arrays configuring the other part are kept to be lighted individually, in other words, in each pulsating period within the period of time, the corresponding LED arrays of the other part are actively controlled to be lighted individually, which is not repeated.

In other words, when the lowest value occurring in each period of the pulsating direct current voltage is detected to cross the full-bright threshold from top to bottom, namely to fall below the full-bright threshold, only part of the n LED arrays are kept to be driven and lighted. Further, then, in the case where the lowest value of the periodically occurring periods is below the full-on threshold, even if the pulsating direct-current voltage exceeds the full-on threshold for a part of the period in each period enough to turn on all of the n LED arrays, only a part of the n LED arrays is kept driven to be turned on. This avoids that different parts of the n LED arrays are switched on frequently with varying pulsating dc voltage, in particular across the full brightness threshold, and thus strobing.

Alternatively, in some embodiments of the present invention, the pulsating dc voltage periodically exhibits a lowest value during the pulsating change, and if the waveform of the pulsating dc voltage in a certain period is relatively stable, the lowest values in different pulsating cycles of the period are all equal or substantially equal, and this same lowest value may be the lowest value of the pulsating dc voltage. The partial LED arrays comprise a first partial LED array having a maximum or next largest number of n LED arrays that can be turned on with the lowest value of the pulsating dc voltage. Therefore, the energy supply of the direct current power supply is fully utilized, and the power utilization efficiency of the n LED arrays is improved.

Optionally, the method in some embodiments of the present invention, further comprising the step of: coordinating i) currents when the n LED arrays are all turned on, and ii) currents when the first portion of the LED arrays are individually turned on, such that a total power of the n LED arrays remains within a neighborhood of the first power value.

Optionally, in the method in some embodiments of the invention, the first portion is dynamically rotationally configured among the n LED arrays. In particular, the first portion of LED arrays is arranged in a first predetermined frequency of rotation/cycling, each configured as a different subset of the n LED arrays, in a different rotation/cycling period. Alternatively, the first portion of the LED arrays is arranged to be rotated/cycled at a first predetermined frequency, each corresponding to a different subset of the n LED arrays during a different rotation/cycling period. Alternatively, the first portion of the LED arrays is cyclically configured at a first predetermined frequency to include different subsets of the n LED arrays, respectively, in different cycles. Alternatively, the first portion of the LED arrays is arranged alternately at a first predetermined frequency, each comprising a different subset of the n LED arrays during a different alternate period.

Step SA-2-NO) further comprises the steps of: actively controlling the plurality of subsets of LED arrays to be cycled on/on at a first predetermined frequency within each of the at least one pulsing periods (in) or across (across) one or more of the at least one pulsing period in response to the lowest value of the pulsating dc voltage falling below a full bright threshold.

Optionally, in the method in some embodiments of the present invention, the plurality of LED array subsets are configured such that the number of their union is greater than the number of the first part of LED arrays.

Optionally, in the method in some embodiments of the invention, the number of LED arrays in the union of the plurality of LED array subsets is n or n-1.

Optionally, in the method in some embodiments of the present invention, the partial LED array further includes a second partial LED array of the n LED arrays, and the step SA-2-NO) further includes the steps of:

the first and second partial LED arrays are actively controlled to alternately or alternately conduct/illuminate at a first predetermined frequency within or across each of the at least one pulsing period in response to the lowest value of the pulsating dc voltage falling below a full brightness threshold.

Of course, in this and other similar embodiments, it is not excluded that there is a third partial LED array or a fourth partial LED array in the n LED arrays, and the first and second partial LED arrays are alternatively turned on under the active control of the control unit. This also applies to other similar embodiments or will not be described again.

Optionally, in the method in some embodiments of the present invention, the step SA-2-NO) further comprises the steps of:

actively controlling at a first predetermined frequency within or across each of the at least one pulsing periods, for example by a control unit comprising a timer, in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, or in response to the lowest value of the periodicity of the pulsating direct current voltage falling from above the full bright threshold to below the full bright threshold: i) at least one of the first partial LED arrays and ii) at least one of the n LED arrays other than the first partial LED array are alternately or alternately turned on/illuminated.

actively controlling at a first predetermined frequency within or across each of the at least one pulsing periods, for example by a control unit comprising a timer, in response to the lowest value of the pulsating direct current voltage falling below a full bright threshold, or in response to the lowest value of the periodicity of the pulsating direct current voltage falling from above the full bright threshold to below the full bright threshold: i) at least one of the partial LED arrays and ii) at least one of the n LED arrays other than the partial LED array are alternately or alternately turned on/lit.

It should be understood that components of the lighting apparatus, the control circuit, the control unit in the hardware devices such as the driving apparatus and the like in other embodiments of the present invention may be configured to perform the methods herein and in other embodiments of the present invention. Particularly in the lighting device and the driving device provided with the floating switch unit, different parts in the n LED arrays can be actively controlled to be lighted in high-frequency rotation, for example, at a first preset frequency through a timer or a pulse generator/counter included in the control unit.

Optionally, the method in some embodiments of the present invention further comprises a step SA-3-NO of one of the following three steps: a) in response to a change in the lowest value of the pulsating direct current voltage across the full bright threshold (e.g., the lowest value of the pulsating direct current voltage decreases from above the full bright threshold to below the full bright threshold, or increases from below the full bright threshold to above the full bright threshold), a changeover lighting between the n LED arrays and the partial LED arrays is performed through a plurality of successive pulsating cycles. b) Each transition between the n LED arrays and the partial LED array is made stepwise in successive pulse periods in response to a change in the lowest value of the pulsed dc voltage across the full brightness threshold. Or c) in response to a change in the lowest value of the pulsating direct current voltage across the full brightness threshold, each transition between the n LED arrays and the partial LED array is done step-by-step through a succession of a plurality of pulsating cycles.

Optionally, in step SA-3-NO), the plurality of pulsation cycles temporally precede the corresponding at least one pulsation cycle in some other embodiments. Specifically, in response to the occurrence of the condition/event (event) that the lowest value of the pulsating direct current voltage crosses the full lighting threshold, the switching lighting between the n LED arrays and the partial LED arrays is dispersed in a first plurality of pulsating cycles to be performed step by step, and after the switching process is completed in a gradual manner, only the partial LED array/the first partial LED array is lighted individually in each of the following first at least one pulsating cycles, and the other partial LED arrays are no longer passively switched to be lighted along with the fluctuation of the voltage. Wherein the first plurality of pulse cycles and the first at least one pulse cycle occur substantially consecutively in time, and from a time perspective, they may be considered to correspond one after the other.

Optionally, the current of the n LED arrays in the fully turned-on state and the current of the first part of LED arrays in the individually turned-on state are complementary in time/waveform, so that the stroboscopic can be reduced to a greater extent.

Here, the conversion process between the n LED arrays and the partial LED arrays is controlled to be performed in a step-by-step manner in a plurality of pulse periods extended/spanned (transition), rather than being performed in two or even the same pulse periods adjacent to each other in front and back. This further avoids abrupt brightness changes caused by sudden complete interchange/switching between the n LED arrays and the partial LED arrays (e.g. occurring within one pulse cycle). Furthermore, in other embodiments, by using a means that the locked part of the LED arrays are individually lit when the minimum pulsating dc voltage value falls below the full-on threshold, the occurrence of low-frequency stroboscopic phenomena when the minimum pulsating dc voltage value of the n LED arrays changes while continuously crossing (crossing) one or more voltage thresholds can be substantially eliminated. In addition, the change smoothness of the luminous flux of the LED array in the process of switching and lighting different parts of the n LED arrays or in the process of switching and lighting the n LED arrays and a certain part of the n LED arrays is improved.

Optionally, in the method in some embodiments of the invention, step SA-3-NO) further comprises step SA-3-NO-1):

coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively (cycle by cycle, or every 2-3 cycles) decreasing and increasing in a plurality of pulse cycles; or

Coordinating the average value of the currents in the n LED arrays which are all conducted and the average value of the currents in the partial LED arrays which are conducted separately, and respectively increasing and decreasing in a plurality of pulse periods; or

And coordinating the current or the average value of the current in the n LED arrays which are all conducted with the current or the average value of the current in the partial LED arrays which are conducted separately, wherein the current or the average value of the current in the n LED arrays respectively shows an overall ascending trend and an overall descending trend in a plurality of pulse periods.

It is of course understood that it is not excluded in this overall upward trend that the individual periods are even with the last period, or even slightly lower. The overall descending trend does not exclude the individual period from being equal to the previous period, or even slightly ascending.

coordinating the relative proportion of the on-time that n LED arrays are fully turned on to the on-time that a portion of the LED arrays are individually turned on, decreasing or increasing in a plurality of pulsing periods; or

In a plurality of pulsing periods, the duration of time during which the n LED arrays are coordinated to be fully turned on is incremented/decremented on a cycle-by-cycle basis, and correspondingly, the duration of time during which the partial LED arrays are individually turned on is decremented/incremented on a cycle-by-cycle basis.

Optionally, in the method in some embodiments of the present invention, the step SA-3-NO-1) further comprises any one of the following substeps:

SA-3-NO-1b) in response to the lowest value of the pulsating direct voltage rising above the full bright threshold, incrementally adjusting the duty cycle/amplitude of the current in the state where the n LED arrays are fully turned on cycle by cycle over a plurality of pulsating cycles, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current in the state where the first portion of the LED arrays are individually turned on cycle by cycle.

Optionally, in the method according to some embodiments of the invention, the first predetermined frequency at least partially provides a self-timer/frequency generator, SA-3-NO-1a) or SA-3-NO-1b), further comprising the steps of:

Optionally, the full bright threshold is adjusted incrementally/decrementally with the period of the pulsating dc voltage by the integration unit, according to an input from a timer.

Optionally, the first threshold value adjusted incrementally/decrementally with the period of the pulsating direct current voltage is generated by an integration operation in response to a magnitude comparison between the pulsating direct current voltage crossing the full bright threshold value and the full bright threshold value, and the first loop and the one bypass loop (or the at least two bypass loops operating alternately at the first frequency) are dynamically switched in response to the pulsating direct current voltage crossing the first threshold value.

Optionally, in the method in some embodiments of the present invention, the plurality of pulsation cycles includes any number of pulsation cycles from 5 to 1000, or the plurality of pulsation cycles lasts 1ms to 1000 ms.

It should be understood that: the determination of the magnitude relationship between the pulsating direct current voltage or the lowest value thereof and the full-bright threshold value can be performed by the control unit collecting electrical signals in some circuit modules in the driving circuit or the lighting device, and the specific electrical signal acquisition position, the determination logic and the setting method of the full-bright threshold value do not limit the present invention. In addition, when the control unit includes a timer and an integration unit coupled to each other, the control unit is operable to dynamically set the full bright threshold or other thresholds. And then the on duty ratio of the first part of LED arrays or the n LED arrays in each/corresponding pulse period is changed, which is also applicable to other embodiments, or is not described again.

In step SA-2) of some embodiments, only a first portion of the n LED arrays are driven to be illuminated in response to the output voltage of the dc power supply being below a full lighting threshold. More preferably, one or more of the first part of LED arrays may be actively controlled to alternately or alternately conduct/illuminate at a first predetermined frequency (e.g. 30kHz, etc.) higher than the mains frequency (typically the mains frequency, e.g. 50HZ or 60HZ) with a second part of the n LED arrays. Here, it should be understood that: with these steps and embodiments thereof, only a portion but not all of the n arrays are lit at any time/at any time during the pulsating cycle of the dc voltage. This ensures to some extent: although the direct current voltage is floated in the pulse period, if the conduction voltage drop of the part of the LED array is lower than the minimum value of the direct current voltage in the pulse period, the part of the LED array can be always driven to be lightened. This also reduces the flickering of the n LED arrays in the pulse period, since it is no longer possible to switch from a state in which part of the LED arrays are lit back to a state in which all n LEDs are lit (passively) as the value of the dc voltage increases from below the full lighting threshold to above the full lighting threshold.

From another perspective, with step SA-1 of some embodiments), when the dc voltage of the full cycle in the pulse cycle is higher than the full bright threshold, all n LED arrays are lit, and if the minimum value or a certain neighborhood of the minimum value occurring in the pulse cycle is lower than the full bright threshold, all n LED arrays are no longer attempted to be turned on by the dynamic configuration of the circuit during the full pulse cycle, although the maximum value and a certain neighborhood of the dc voltage in the pulse cycle may still be greater than the full bright threshold and thus sufficient to turn on all n LED arrays. Further alternatively, a plurality of partial LED arrays, such as a first partial LED array, a second partial LED array, or also a third partial LED array, etc., may be illuminated alternately/alternately at a first predetermined frequency. Still further, it optionally comprises the steps of: keeping at least one LED array of the n arrays other than the rotated plurality of partial LED arrays normally on. Optionally, the first part of LED array, the second part of LED array and the third part of LED array have the same turn-on voltage drop.

Optionally, if no normally bright LED array is configured, each part of the LED arrays in the plurality of parts of LED arrays may be respectively configured with a maximum number or a next largest number of the n LED arrays that can be turned on by the lowest value of the pulsating direct current voltage; on the other hand, if a normally-on LED array, which is not among the LED arrays of the plurality of portions, is configured in the n LED arrays, the number of LED arrays of each portion in the LED arrays of the plurality of portions, for example, the first LED array portion, and the normally-on LED array portion, that is, the sum of the number of the first LED array portion and the normally-on at least one LED array portion, may be configured to be the maximum number or the next largest number that the lowest value of the pulsating dc voltage can be turned on in the n LED arrays. This number configuration according to the on-state voltage drop of the n LED arrays allows to adapt (adapted for) the pulsating change of the dc voltage with respect to the full brightness threshold with maximum efficiency in the n LED arrays. Also, a) a union of a plurality of partial LED arrays that are rotated, or b) a union of a plurality of partial LED arrays and at least one LED array (if any) that is normally bright, the number of LED arrays in either of them may be configured to be n or n-1. This quantity configuration is such that: from the perspective of one or more successive pulsing periods, all n or n-1 arrays are in a state of being actively alternately lit or normally lit at a first predetermined frequency, and thus, the total light-emitting area of the n LED arrays may remain substantially unchanged as a whole, although at least a portion of the voltage values in the pulsing periods are below the full-on threshold, resulting in the dc voltage being insufficient to turn on all n LED arrays, relative to a case where the dc voltage is sufficient (the minimum voltage value in the pulsing periods is greater than the full-on threshold) and all n LED arrays are turned on.

Preferably, the process of switching/converting/transitioning between step SA-1) and step SA-2) is not accomplished in the following two ways: i) completing the conversion process in the first pulse cycle, for example, detecting that the lowest value of the direct current voltage is reduced below a full bright threshold value in the first pulse cycle; ii) the above-mentioned conversion process is completed in one cycle, or two cycles adjacent to each other, for example, in a first pulse cycle, if the dc voltage minimum is detected to be below the full brightness threshold, then in a second subsequent pulse cycle.

In some embodiments of the present invention, the assignment of the transition between "n LED arrays fully lit" and "partial LED arrays alternately lit" is done gradually/gradually over a plurality of pulsing periods. Specifically, for the above-mentioned conversion process from "n LED arrays are all lit" to "partial LED arrays are lit alternately" or from "partial LED arrays are lit alternately" to "n LED arrays are lit entirely", the method of the related embodiment may further include the step of gradually adjusting (e.g., incrementally or decreasingly) the relative ratio between the duration of "partial LED array is lit alternately" and the duration of "n LED arrays are lit entirely" through a plurality of consecutive pulsation cycles, or gradually adjusting the duty ratio/value/average value of the current corresponding to "partial LED array is lit alternately" and the current corresponding to "n LED arrays are lit entirely" in each pulsation cycle, for example, one is gradually increased and the other is gradually decreased.

Generally, in some commercial power application scenarios, the dc voltage is a pulsating dc voltage outputted after rectifying a commercial power input, the fluctuation of the commercial power is generally not more than ± 10% or ± 20%, and the fluctuation is sporadic or gradual, but not completely unpredictable, extremely severe, for example, although the commercial power varies between a higher level and a lower level, the frequency of the variation is not high, and the holding time at the high level and the low level is relatively long, for example, 1 hour, or occasionally a short fluctuation, for example, a voltage spike, may be filtered out by a suitable hardware device, for example, a capacitor, or even if not filtered out, because of the sporadic occurrence, may be accepted. Sometimes, the dc voltage, although overall at a low level, has a maximum value in its pulse period that is still greater than the full lighting threshold, i.e. sufficient to light all n LED arrays. The method of some embodiments of the invention will be further described herein, taking this case as an example, but it should be understood that: the method of the related embodiment of the invention is not limited to such fluctuations of the dc voltage with respect to the full bright threshold, but is also applicable to situations where the dc voltage drops to a lower level, for example where the maximum value of the dc voltage in its ripple period also drops below the full bright threshold, i.e. the dc voltage fluctuates with respect to other lower voltage thresholds or across lower voltage intervals. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications.

As above, since the maximum value and a certain neighborhood of the maximum value in the pulse period of the dc voltage are still greater than the full lighting threshold, in the process of the transition (or gradual transition) between the two states of "n LED arrays are all lit" and "part of LED arrays are alternately lit", all n LED arrays are lit by the dc voltage greater than the full lighting threshold in a plurality of pulse periods (for example, the greater dc voltage may be located in the neighborhood of the maximum value in each pulse period); some of the LED arrays are turned on (or alternately turned on) at a time other than when all of the n LED arrays are turned on. And i) the duty ratio/value/average value of the current for lighting part of the LED arrays in each of the plurality of pulse periods is reduced in a coordinated and rotating manner, and the duty ratio/value/average value of the current for lighting all the n LED arrays in each of the plurality of pulse periods is increased synchronously; or ii) the duty ratio/value/average value of the current for lighting part of the LED arrays in each plurality of pulse periods is increased in coordination with the rotation, and the duty ratio/value/average value of the current for lighting all the n LED arrays in each plurality of pulse periods is decreased synchronously. Alternatively, the method in some embodiments of the invention may further comprise the step of: a) in a plurality of pulse periods, the duty ratio/average value/amplitude of current pulses for lighting part of the LED arrays are reduced in a coordinated and rotating manner, and the duty ratio/average value/amplitude of current pulses for lighting all n LED arrays are increased synchronously; or b) coordinating the increasing of the duty ratio/average value/amplitude of the current pulse for alternately lighting part of the LED arrays in a plurality of pulse periods, and synchronously, decreasing the duty ratio/average value/amplitude of the current pulse for lighting all the n LED arrays.

Optionally, I) the current pulses for alternately illuminating a portion of the LED arrays are temporally complementary to ii) the current pulses for illuminating all n LED arrays (over successive multiple pulsing periods) such that the n LED arrays have only the two mutually switched states described above, and there is no fully extinguished state and thus stroboscopic.

In another embodiment of the present invention, a method for controlling an LED array is further provided, including: at a drive circuit for driving a series of n LED arrays powered by a dc power supply:

SA-1): the n LED arrays are provided with control signals/power,

SA-2): in response to the periodic voltage output by the dc power supply passing (transition) a plurality of conduction threshold changes (in some embodiments, the conduction threshold may also be referred to as a threshold), a plurality of LED arrays corresponding to the plurality of conduction thresholds (e.g., one-to-one correspondence) in the n LED arrays are alternately turned on by the control signal.

SA-1): a control signal is provided to the n LED arrays,

SA-2): in response to the variation of the minimum value of the periodic voltage output by the direct current power supply through a plurality of conduction thresholds, a plurality of groups of LED arrays corresponding to the plurality of conduction thresholds (for example, one-to-one correspondence) in the n LED arrays are respectively lightened by the control signal in a plurality of periods of the groups. That is, only one set of LED arrays is illuminated during a first plurality of cycles (aftermarket of period) until the voltage changes after the first plurality of cycles, such as reaching a first bypass threshold.

Optionally, in the method in some embodiments of the present invention, the plurality of conduction thresholds includes a full bright threshold corresponding to a high voltage group LED array in the plurality of groups of LED arrays, including all n LED arrays; and the plurality of conduction thresholds further comprise at least one conduction threshold lower than a full brightness threshold, the at least one conduction threshold respectively corresponds to at least one other low-voltage group LED array in the plurality of groups of LED arrays, and the number of the LED arrays in the at least one low-voltage group LED array is less than or equal to a proper subset of the n-1n LED arrays. That is, if the output voltage of the dc power supply is below the full bright threshold, it is not sufficient to turn on all n LED arrays.

Optionally, in the method in some embodiments of the present invention, the dc power supply outputs a pulsating dc voltage; each of the plurality of sets of multiple periods includes a plurality of pulse periods in succession. And, step SA-2) further comprises step SA-2-NO): switching between each two of the LED arrays in the plurality of groups through a plurality of groups of pulse cycles; the switching between every two of the multiple groups of LED arrays comprises switching from a high-voltage group of LED arrays to a first group of LED arrays in at least one low-voltage group of LED arrays, and/or switching between multiple low-voltage group of LED arrays included in at least one low-voltage group of LED arrays.

SA-1): the n LED arrays are provided with control signals/power,

SA-2): and responding to the change of the periodic voltage output by the direct current power supply among a plurality of voltage intervals, and alternately lighting a plurality of groups of LED arrays corresponding to the plurality of voltage intervals in the n LED arrays by the control signal.

SA-1): a control signal is provided to the n LED arrays,

SA-2): in response to the periodic voltage minimum value output by the direct current power supply changing among a plurality of voltage intervals, a plurality of groups of LED arrays corresponding to the voltage intervals (for example, one-to-one correspondence) in the n LED arrays are respectively lightened by the control signal in a plurality of groups of periods (multiple complexity of period). That is, in each of the plurality of cycles (each of the plurality of cycles), only one of the LED arrays is turned on until the voltage enters the second voltage interval from the first voltage interval after, for example, the first plurality of cycles, and then another LED array corresponding to the second voltage interval is turned on.

Optionally, in the method in some embodiments of the present invention, the multiple voltage intervals include a high voltage interval higher than a full brightness threshold, where the high voltage interval corresponds to a high voltage group LED array in the multiple groups of LED arrays, and includes all n LED arrays; and at least one low-voltage group LED array corresponding to at least one low-voltage interval which is lower than the full-bright threshold value in the plurality of voltage intervals is a proper subset of the n LED arrays. In other words, the plurality of voltage intervals includes a high voltage interval above a full bright threshold, corresponding to a full set of n LED arrays; and, a voltage interval of the plurality of voltage intervals below the full bright threshold corresponds to a proper subset of the n LED arrays. When the output voltage of the direct current power supply is in a voltage interval lower than a full-bright threshold value, all the n LED arrays are not enough to be conducted.

Here, similar to some other embodiments, the transition between each two of the LED arrays is performed and completed step by step (gradually) over multiple periods, rather than quickly and in real time in one period in response to the pulsating dc voltage crossing a certain threshold. By this switching means of the present embodiment, abrupt changes in luminous flux that may occur during switching are dispersed over multiple pulsing periods to homogenize and smooth out such changes in luminous flux, and thus, reduce the degree of variation in the emission of the LED array.

Optionally, in the method in some embodiments of the invention, step SA-2-NO) further comprises step SA-2-NO-1): coordinating i) the current or its average value in the group of LED arrays to which it is switched among the plurality of groups of LED arrays, and ii) the current or its average value in the group of LED arrays to which it is switched, increments and decrements, respectively, over a plurality of pulsing periods of the/switching occurring/corresponding group of the current group.

Optionally, in the method in some embodiments of the invention, the plurality of sets of the plurality of pulse cycles comprises a first plurality of pulse cycles, and the step SA-2-NO-1) further comprises any one of the following sub-steps:

i) When the output voltage of the direct current power supply falls into a first low-voltage interval of at least one low-voltage interval from the high-voltage interval, within a first group of a plurality of pulse cycles, the current or the average value of the current in the high-voltage group LED array is adjusted in a descending manner cycle by cycle, and the current or the average value of the current in the first group LED array is adjusted in a synchronous ascending manner cycle by cycle; or,

ii) when the output voltage of the dc power supply rises from a first low voltage interval of the at least one low voltage interval to a high voltage interval, incrementally adjusting the current or an average thereof in the high voltage group of LED arrays cycle by cycle over a first plurality of pulsing cycles, and, synchronously, incrementally adjusting the current or an average thereof in the first group of LED arrays cycle by cycle;

thus, it is preferred that the electrical power/luminous flux during conversion of the high voltage group LED array and the first group LED array remains substantially stable and the same as before switching.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2) or similar steps therein, and the sub-steps of these steps may further comprise any of 4 sub-steps including the alternative (alternative) two sub-steps in the following step SA-2-a) or the alternative (alternative) two sub-steps in SA-2-b):

SA-2-a) substep 1. in response to the voltage of the dc power source being in a first voltage interval, within the duration of the first voltage interval, e.g. by a periodic signal generated by a timer/frequency generator or a trigger signal generated by a re-coordinating trigger, etc., actively controlling the subset/portions of the n LED arrays corresponding to the first voltage interval to be cycled on/on; wherein the voltage of the DC power supply is within any voltage sub-interval or at any voltage level in the first voltage interval, and the subsets of the n LED arrays corresponding to the first voltage interval can be cyclically switched on (for example, at a high frequency of tens of k), or

Sub-step 2. actively controlling a plurality of subsets of the n arrays corresponding to the first voltage intervals to be cycled/turned on during the duration of each of the plurality of first voltage intervals, for example, by a periodic signal generated by a timer/frequency generator or a trigger signal generated by a coordinated flip-flop; wherein the voltage of the dc power source is within any voltage sub-interval or at any voltage level in the first voltage interval, and a plurality of subsets of the n LED arrays corresponding to the first voltage interval can be cyclically turned on (e.g. at a high frequency of several tens of k).

Wherein the first voltage interval has a voltage range below a full bright threshold; or,

SA-2-b) sub-step 3. periodically generating a first voltage interval in response to a voltage variation of the dc power source, actively controlling a plurality of subsets of the n arrays corresponding to the first voltage interval such that the plurality of subsets are cyclically turned on/illuminated; the frequency of the cyclic conduction is greater than, less than or equal to the frequency of the voltage change of the direct-current power supply; wherein the voltage of the DC power supply is within any voltage sub-interval or at any voltage level in the first voltage interval, and the subsets of the n LED arrays corresponding to the first voltage interval can be cyclically switched on (for example, at a high frequency of tens of k), or

Sub-step 4. during the duration of the first voltage intervals, actively controlling a plurality of subsets of the n arrays corresponding to the first voltage intervals to be alternately lighted; wherein one of the plurality of first voltage intervals, or two or more consecutive ones, correspond to only one of the plurality of subsets. In other words, only one of the subsets is lit up in 1 of the first voltage intervals, or 2-5 consecutive ones.

The first voltage interval has a voltage range below a full bright threshold. Of course, it is not excluded that a second voltage interval is also provided, below the lower limit of the first voltage interval (or may be referred to as a first bypass threshold), or lower. In other words, the first voltage interval may be defined by both the full bright threshold and the first bypass threshold as an upper limit (upper bound) and a lower limit (lower bound) of the first voltage interval, respectively. And entering a first voltage interval if the voltage of the direct current power supply is between the full brightness threshold and the second threshold. In other words, the voltage of the dc power supply falls below the full bright threshold into a first voltage interval, and if the dc voltage continues to fall below the first bypass threshold, into a second voltage interval lower than the first voltage interval. Correspondingly, the method of some embodiments of the present invention defined by the first voltage interval, the at least one voltage interval, may also be defined by steps based on a plurality of thresholds, such as the full bright threshold, the first bypass threshold, and the like. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications.

In addition, the alternate lighting means: the LED arrays of the plurality of subsets will be repeatedly lit up in sequence, i.e. sub-steps 4, etc. will be performed cyclically/repeatedly as the first voltage interval is repeated.

Optionally, the LED arrays in the subsets that are alternately switched on, such as the first subset and the second subset, or also the third subset, are not identical, and there may or may not be an intersection between the two.

Optionally, in the LED array control method of some embodiments of the present invention, the corresponding plurality of subsets of the first voltage interval among the n LED arrays includes a first subset/first partial LED array and a second subset/second partial LED array;

step SA-2-a) further comprises the sub-steps of:

SA-2-a-1) alternately turns on the first and second portions of LED arrays for the duration of the first voltage interval.

Step SA-2-b) further comprises the sub-steps of:

SA-2-b-1) in a cyclic manner, the first part of the LED array and the second part of the LED array are respectively conducted to two first voltage intervals which occur adjacently. For example, when the dc power supply outputs a pulsating dc voltage, first voltage intervals a and b occur twice in sequence in a first pulsating cycle, and are located on both sides of a peak value of a first pulsating wave, only a first part of LED arrays are turned on in the first voltage interval a, and a second part of LED arrays are turned on individually in the first voltage interval b; and in the subsequent pulse period, circularly conducting the first part of LED array and the second part of LED array in this way. In this case, the period of the cyclic conduction of the first and second LEDs can be regarded as the same as the period of the pulsating dc voltage of the dc power supply.

Of course, alternatively, in two different first voltage intervals a and b occurring successively in the first ripple period described above, only the first part of the LED array may be turned on, and in two first voltage intervals occurring in the subsequent second ripple period, only the second part of the LED array may be turned on, in which case the frequency of the cyclic conduction of the first part and the second part of the LEDs may be considered to be less than the frequency of the ripple dc voltage of the dc power supply. Further alternatively, in the single first voltage interval a in the first ripple period, the first partial LED array and the second partial LED array may be alternately turned on repeatedly (for example, several tens of times), and the alternating frequency thereof is greater than the frequency of the ripple dc voltage of the dc power supply.

The number of LED arrays in the union of the first part of LED arrays and the second part of LED arrays is greater than the maximum number of LED arrays in the n LED arrays that the first voltage interval is sufficient to light up. For example, the n LED arrays include 5 LED arrays: n1, N2, N3, N4, N5. Wherein, N1, N2 and N5 belong to the first part of LED array, and N1, N2, N3 and N4 belong to the second part of LED array. And only N1, N2, N3, N4 can be turned on because the first voltage interval is not enough to turn on all 5 Led arrays below the predetermined voltage threshold. In addition, the conduction voltage drop of N5 is lower than the sum of the conduction voltage drops of N3 and N4, so the first voltage interval is also enough to conduct the first part of the LED array. During the rotation, the union of the first part of LED arrays and the second part of LED arrays comprises N1, N2, N3, N4, N5. That is, if the rotation frequency is proper, all 5 LED arrays can have luminous flux generated in the first voltage interval. In other words, when the first part of LED arrays and the second part of LED arrays are turned on alternately, the LED arrays capable of emitting light in the n LED arrays are a union of the first part of LED arrays or the second part of LED arrays, and therefore, in terms of perception, the area capable of emitting light of the n LED arrays is larger than the area capable of emitting light when the first part of LED arrays or the second part of LED arrays are turned on individually.

Alternatively, in the LED array control method of some embodiments of the present invention, in step SA-2-a-1) or the like, the alternate frequency of the alternate conduction is any one of [0.5kHz,1000kHz ].

Optionally, in the LED array control method according to some embodiments of the present invention, the first part of LED arrays and the second part of LED arrays are both proper subsets of n LED arrays, and the first part of LED arrays and the second part of LED arrays have intersection or non-intersection.

Optionally, in the LED array control method according to some embodiments of the present invention, if the first part of LED arrays and the second part of LED arrays do not intersect, the control method further includes: when the output voltage of the direct current power supply is enough to turn on a first LED array in the n LED arrays, the first LED array is kept normally on, wherein the first LED array does not belong to the LED arrays of the first part/subset and does not belong to the LED arrays of the second part/subset. The first LED array is connected with the n LED arrays in series and keeps normally bright, so that the energy efficiency of the driving circuit where the n LED arrays are located is improved.

Optionally, in the LED array control method according to some embodiments of the present invention, the first part of LED arrays and the second part of LED arrays respectively include one or more LED arrays of the n LED arrays, or one or more LEDs of the n LED arrays connected in series except for the at least one LED array at the tail (e.g., one or more LED arrays connected to the negative pole of the power supply) to adapt to the first voltage interval.

Optionally, the control method/circuit structure related to the control method of some embodiments of the present application and herein may be referred to in the related description including the summary under the heading "floating/common ground circuit structure".

Optionally, in the LED array control method according to some embodiments of the present invention, the union of the first part of LED arrays and the second part of LED arrays covers/covers all of the n LED arrays or n-1, so that when the second part of LED arrays and the first part of LED arrays are alternately turned on, especially at a high frequency, a (light source) light emitting area can be maintained (substantially) the same as that of the n LED arrays when they are all turned on by a sufficient dc power supply voltage, and stroboscopic is greatly reduced.

Optionally, in some embodiments, the number of the first part of LED arrays is the maximum number/next largest number of LED arrays that can be lit in the n LED arrays in the first voltage interval, and the number of the second part of LED arrays is the next largest number/maximum number of LED arrays that can be lit in the n LED arrays in the first voltage interval. For example, the n LED arrays include 5 LED arrays: n1, N2, N3, N4, N5. Wherein, N1, N2 and N5 belong to the first part of LED array, and N1, N2, N3 and N4 belong to the second part of LED array. And only N1, N2, N3 and N4 can be conducted, and the number of the first voltage interval is 4, because the first voltage interval is not enough to conduct all 5 Led arrays. In addition, the conduction voltage drop of N5 is lower than the sum of the conduction voltage drops of N3 and N4, so the first voltage interval is also enough to conduct the first part of the LED array. During the rotation, the first part of the LED arrays has a first voltage interval, and the next largest number of LED arrays can be lit out of 5 LED arrays: 3, the number of the medicine is less than that of the medicine. The second part of the LED arrays has a first voltage interval of the maximum number of LED arrays that can be lit out of the 5 LED arrays: 4 of the Chinese herbal medicines.

Optionally, the number of the first part of LED arrays is the same as the number of the second part of LED arrays. For example, in the above-described embodiment, the n LED arrays include 5 LED arrays: n1, N2, N3, N4, N5. Wherein, N1, N2, N3 and N5 belong to the first part of LED array, and N1, N2, N3 and N4 belong to the second part of LED array. And because the power of the first part of LED arrays and the second part of LED arrays is kept basically the same, when the two parts of LED arrays are switched on, especially switched on by high frequency, the same power is always dispersed on the same number of LEDs, thereby avoiding the change of brightness/darkness caused by the repeated concentration/dispersion of the same energy.

Optionally, in the LED array control method according to some embodiments of the present invention, the dc power supply outputs rectified pulsating dc voltage, the first part of LED arrays and the second part of LED arrays have the same conduction voltage drop, and correspondingly, in the alternate conduction process, the currents flowing through the first part of LED arrays and the second part of LED arrays are controlled by the switching unit to be square waves with complementary shapes or trapezoid-like square waves with smoother rising and falling edges, and the amplitudes are substantially the same, and the duty ratios are 50%, which is more favorable for brightness uniformity and improves the light emitting effect. Of course, it is understood that if the conduction voltage drops of the first part of LED arrays and the second part of LED arrays are different, the waveforms of the currents flowing in the first part of LED arrays and the second part of LED arrays may still be complementary in shape, but the amplitudes may optionally be different in inverse proportion to the voltage, and the duty cycle may not be 50% any more, but may be 4:6 or other ratios. The purpose of this part is to adjust the power and luminous flux of the first part LED array and the second part LED array during the alternating conduction process, and the difference or stroboflash of the lighting effect caused by the alternating conduction is not substantially formed to the outside, and in this purpose, the values of the duty ratio, the current amplitude, etc. can be adjusted according to the needs, and are not limited to the exemplary values given above.

Optionally, in the LED array control method according to some embodiments of the present invention, the plurality of first voltage intervals occur periodically with the pulsating dc voltage. The first voltage intervals occur in the same voltage pulse period in time or are distributed in a plurality of continuous pulse periods.

Optionally, in the LED array control method according to some embodiments of the present invention, the step SA-2-a-1) or SA-2-b-1) or similar step may further include: SA-2-ab-1) coordinate the currents in the first and second partial LED arrays during the alternating conduction such that the power of the n LED arrays is maintained in the vicinity of the first power value.

Optionally, in the LED array control method according to some embodiments of the present invention, the step SA-2-a-1) or SA-2-b-1) or similar step may further include:

and adjusting the current in the first part of LED arrays and the second part of LED arrays according to the conducting voltage drops of the first part of LED arrays and the second part of LED arrays respectively, so that the relative change rate of the power of the first part of LED arrays and the second part of LED arrays is less than a preset percentage. Wherein the predetermined percentage is less than 10%, such as 0.5%, 2%, or 5%.

Optionally, in the LED array control method according to some embodiments of the present invention, step SA-2-ab-1) or similar steps may further include:

SA-2-ab-1-1), dynamically controlling the current in the first part of LED arrays to decrease synchronously with the current in the second part of LED arrays before and/or after and/or during the switching from the first part of LED arrays to the second part of LED arrays, such that the decrease in power or luminous flux of the first part of LED arrays is compensated/counteracted by the increase in power of the second part of LED arrays, and

SA-2-ab-1-2) for dynamically controlling the current in the second part of LED arrays to decrease synchronously with the current in the first part of LED arrays, during switching back and forth and/or from the second part of LED arrays to the first part of LED arrays, so that the power or luminous flux decrease of the second part of LED arrays is compensated/counteracted by the power increase of the first part of LED arrays.

Optionally, in the LED array control method according to some embodiments of the present invention, the step SA-2-ab-1-2) or the similar step may further include:

in the transition process of switching from the second part of LED arrays to the first part of LED arrays, controlling the current in the first part of LED arrays to increase synchronously before the descending amplitude of the current in the second part of LED arrays exceeds a preset amplitude value; and step SA-2-ab-1-1) further comprises:

And in the transition process of switching from the first part of LED arrays to the second part of LED arrays, controlling the current in the second part of LED arrays to increase synchronously before the descending amplitude of the current in the first part of LED arrays exceeds a preset amplitude value. The preset amplitude value is optionally any value between 0% and 5%.

The methods in some embodiments of the invention may be implemented in a driver circuit or a control circuit in some embodiments. For example, when m is 1 and x is 0 in the driving circuit, i.e. there is only one common ground switch, there is no floating ground switch, and both the current limiting device and the common ground switch can be implemented as linear current sources. The control method for n (e.g., 2) LED arrays implemented based on the driving/control circuit of these embodiments may include the steps of:

detecting a signal related to an external power supply voltage within the driving circuit; and judging the magnitude relation between the voltage at the two ends of the external power supply and the conduction voltage drop of the first load and the conduction voltage drop of the second load according to the signal, and controlling the conduction or the cut-off of the first current source according to the judgment result.

Optionally, in the control method of some embodiments, the controlling of the first current source further includes:

controlling the first current source to be switched off in response to the external power supply voltage being greater than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load to form a second energy loop: external power source → first load → second current source → external power source; and

In response to the external power supply voltage being less than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load, controlling the first current source to conduct to form a first energy loop: external power → first load → first current source → external power.

Optionally, the control method in some embodiments further includes the steps of:

before and after switching of the first energy loop and the second energy loop, coordinating the current of the first current source and the current of the second current source such that a rate of change of a sum of the power of the first load and the second load does not exceed a predetermined percentage.

Optionally, in the control method of some embodiments, wherein the first load and the second load are lighting loads, the step of coordinating the currents further comprises:

adjusting currents in the first load and the second load according to conduction voltage drops of the first load and the second load respectively, so that the change rate of the sum of the luminous fluxes of the first load and the second load before and after switching is smaller than a preset percentage; the predetermined percentage is less than 10%.

Optionally, in some embodiments, the control method further comprises: synchronously controlling the current in the first current source to decrease with the current in the second current source during the transition of the switching of the first energy loop and the second energy loop, so that the decrease of the first load power is compensated by the increase of the second load power; alternatively, the current in the first current source is controlled synchronously to increase with decreasing current in the second current source, so that the decrease in power of the second load is compensated by the increase in power of the first load.

Optionally, in some embodiments, the control method further comprises:

during a transition from the second energy circuit to the first energy circuit, adjusting the current in the first current source to increase synchronously before the current in the second current source decreases by more than a predetermined percentage relative to the current before the transition begins; and/or

During a transition from the first energy loop to the second energy loop, the current in the second current source is controlled to increase synchronously before the current in the first current source decreases by more than a predetermined percentage relative to the current before the transition begins.

Optionally, in some embodiments, the control method further comprises:

the current controlling the second current source in the second energy loop decreases with an increase of the external supply voltage or an average value thereof, and/or,

the current of the first current source in the first energy loop is controlled to be larger than the current of the second current source in the second energy loop.

Optionally, the control method in some embodiments, wherein the external power source provides a rectified pulsating direct current voltage; and, the control method further comprises the steps of:

Step S8-1) if the lowest value of the pulsating direct current voltage is sufficient to turn on the first load and the second load, controlling the first current source to be turned off to keep operating the second energy loop during a corresponding pulsation period of the external power source: external power source → first load → second current source → external power source;

step S8-2) if the lowest value of the pulsating direct current voltage is not enough to turn on the first load and the second load, controlling the first current source to turn on to keep operating the first energy loop during a corresponding pulsation period of the external power source: external power → first load → first current source → external power.

Optionally, the control method in some embodiments, further comprising step S8-3):

switching the second energy circuit and the first energy circuit through a plurality of continuous pulse cycles in response to the lowest value of the pulsating direct current voltage crossing the sum of the conduction voltage drops of the first load and the second load; or

Switching between the second energy circuit and the first energy circuit in steps over successive periods of the ripple in response to the lowest value of the pulsating direct voltage crossing the sum of the conduction voltage drops of the first load and the second load; or

Each switching between the second energy circuit and the first energy circuit is done in steps through a consecutive plurality of ripple cycles in response to a change in the lowest value of the pulsating direct voltage across the sum of the conduction voltage drops of the first load and the second load.

Optionally, in the control method of some embodiments, the method further includes, during the switching between the second energy circuit and the first energy circuit, the steps of:

coordinating the average value of the current in the second energy loop with the average value of the current in the first energy loop, and respectively decreasing and increasing in a plurality of pulse periods; or

The current or the average value thereof in the second energy loop is coordinated to be monotonically increased and monotonically decreased respectively in a plurality of pulsation periods with the current or the average value thereof in the first energy loop.

Optionally, in some embodiments, the control method further includes, during the switching between the second energy circuit and the first energy circuit, the step of:

coordinating the relative proportion of the second energy circuit operating time to the first energy circuit operating time to decrement or increment over a plurality of pulse periods; or

In a plurality of pulsation cycles, the operating time of the second energy circuit is coordinated to be incremented/decremented cycle by cycle, and correspondingly, the operating time of the first energy circuit is decremented/incremented cycle by cycle.

Optionally, in some embodiments, the control method further comprises:

SA-3-NO-1a) in response to the lowest value of the pulsating dc voltage falling below the sum of the conduction voltage drops of the first and second loads, adjusting the duty cycle/amplitude of the current in the second energy loop progressively cycle by cycle over a plurality of pulsation cycles, and, synchronously, adjusting the duty cycle/amplitude of the current in the first energy loop progressively cycle by cycle; or,

SA-3-NO-1b) in response to the lowest value of the pulsating dc voltage rising above the sum of the conduction voltage drops of the first and second loads, incrementally adjusting the duty cycle/amplitude of the current in the second energy loop cycle by cycle over a plurality of pulsation cycles, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current in the first energy loop cycle by cycle;

wherein the current in the second energy loop and the current in the first energy loop are complementary in time/waveform, and the plurality of pulse periods comprise any number of pulse periods from 5 to 1000, or the plurality of pulse periods last from 1ms to 1000 ms.

The methods in some embodiments of the invention may be implemented in a driver circuit or a control circuit in some embodiments. For example, when m is 1 and x is 1 in the driving circuit, that is, 1 common-ground switching unit and 1 floating-ground switching unit are configured, and these two switching units are respectively used for coupling 1 light-emitting load. While both the current limiting device and the common ground switch may be implemented as linear current sources. The control method for n (e.g. 2) LED arrays implemented based on the driving circuit or the control circuit of such an embodiment may include the steps of:

detecting a signal within the drive circuit associated with/reflecting the external supply voltage,

Judging the relationship between the external power voltage and the conduction voltage drop of the first load and the conduction voltage drop of the second load,

according to the judgment result, the switch and the first current source are controlled to be switched on or off, so that the switching between the following two modes is realized:

in the first mode: when the external power supply voltage is greater than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load, the change-over switch and the first current source are cut off to form a third energy loop, and the energy circulation path of the third energy loop is as follows: external power source → first load → second current source → external power source, supplying energy to the first load and the second load;

in the second mode: when the external power voltage is smaller than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load and larger than the larger value of the conduction voltage drop of the first load and the conduction voltage drop of the second load, controlling the change-over switch and the first current source so as to alternately switch between a first state and a second state at a first preset frequency;

the first state is that the switch is turned off and the first current source is turned on to form a first energy loop, and an energy circulation path of the first energy loop is as follows: external power source → first load → first current source → external power source; the second state is that the change-over switch is switched on and the first current source is cut off to form a second energy loop; the energy circulation path of the second energy loop is as follows: external power → change over switch → second load → second current source → external power.

Optionally, in the control method of some embodiments, the current of the second current source in the first mode is controlled to decrease with an increase in the external power supply voltage or an average value thereof, and/or the current of the first current source and the current of the second current source in the second mode are controlled to be larger than the current of the second current source in the first mode.

Optionally, in the control method of some embodiments, the external power supply provides a rectified pulsating direct current voltage; the first predetermined frequency is higher than the power frequency; thereby helping to reduce low frequency stroboscopic.

The first mode further comprises: if the lowest value of the pulsating direct current voltage is larger than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load, the change-over switch and the first current source are cut off so as to keep operating the third energy loop in the corresponding pulsation period of the external power supply;

the second mode further includes: and if the lowest value of the pulsating direct current voltage is smaller than the sum of the conduction voltage drop of the first load and the conduction voltage drop of the second load and is larger than the larger value of the conduction voltage drop of the first load and the conduction voltage drop of the second load, controlling the change-over switch and the first current source so as to keep alternately switching between the first state and the second state at a first preset frequency in the corresponding pulsating period of the external power supply.

Optionally, the control method of some embodiments further includes the steps of:

switching between the first mode and the second mode over successive periods of the ripple in response to a lowest value of the ripple DC voltage crossing a sum of the conduction voltage drops of the first load and the second load; or

Switching between the first mode and the second mode in steps over successive periods of the ripple in response to a lowest value of the pulsating direct voltage crossing a sum of the conduction voltage drops of the first load and the second load; or

Each transition between the first mode and the second mode is accomplished in steps through a succession of a plurality of ripple cycles in response to a change in the lowest value of the pulsating direct voltage across the sum of the conduction voltage drops of the first load and the second load.

Optionally, in the control method of some embodiments, the step of switching between the first mode and the second mode further includes:

coordinating the average value of the current in the first mode with the average value of the current in the second mode to respectively decrease and increase in a plurality of pulse periods; or

Coordinating i) the current or the average thereof in the first mode with ii) the current or the average thereof in the second mode to monotonically increase and monotonically decrease, respectively, over a plurality of ripple cycles.

coordinating the relative proportion of the second mode's on-time to the first mode's on-time, decreasing or increasing over a plurality of pulsing periods; or

The run time of the second mode is coordinated to be incremented/decremented cycle by cycle in a plurality of pulsing cycles, and correspondingly, the run time of the first mode is decremented/incremented cycle by cycle.

Optionally, in the control method of some embodiments, the step of coordinating the currents in the second mode and the first mode further includes:

SA-3-NO-1a) in response to a lowest value of the pulsating direct current voltage falling below a sum of conduction voltage drops of the first load and the second load and being greater than a larger value of the conduction voltage drop of the first load and the conduction voltage drop of the second load, adjusting the duty cycle/amplitude of the current in the first mode cycle by cycle in a decreasing manner over a plurality of pulsation cycles, and, synchronously, adjusting the duty cycle/amplitude of the current in the second mode cycle by cycle in an increasing manner; or,

SA-3-NO-1b) in response to the lowest value of the pulsating dc voltage rising above the sum of the conduction voltage drops of the first and second loads, incrementally adjusting the duty cycle/amplitude of the current of the first mode cycle by cycle over a plurality of pulsation cycles, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current of the second mode cycle by cycle;

Wherein the current of the second mode and the current of the first mode are complementary in time/waveform, and the plurality of ripple periods comprises any number of ripple periods from 5 to 1000, or the plurality of ripple periods for switching between the second mode and the first mode has a duration from 1ms to 1000 ms.

It should be understood that: the components, units, and modules of the driving circuit/device and the lighting device may be implemented as corresponding entity devices by hardware such as a comparator, a timer, a delay circuit, and a trigger, and may also be understood as functional modules that are necessary to implement the steps of the related program flow or the steps of the method. Therefore, in some embodiments of the present invention, the method may be implemented mainly by a computer program/method described in the specification, and in other embodiments, the method may be implemented as a related entity apparatus by hardware.

In another embodiment of the present invention, a driving device for use in a lighting device is also presented, comprising a control unit configured to perform any one of the control methods/control methods etc. or steps thereof in the present application.

In another embodiment of the present invention, there is also provided a driving circuit or a control circuit for use in a lighting device, including a control unit configured to: any one of the control methods/driving methods and the like or steps thereof in the present application is executed when the control circuit is operated or in an operating state.

In another embodiment of the present invention, there is also provided a lighting device, including: a control unit configured to: any one of the control methods/driving methods and the like in the present application or steps thereof is executed when the driving circuit or the control circuit is operated or in an operating state.

In another embodiment of the present invention, a lighting device is further proposed, which is configured to: any one of the control methods/driving methods and the like in the present application or steps thereof is executed when the lighting device is operated or in an operating state.

There is also provided in another embodiment of the present invention a lighting device, including one or more circuit modules configured to: any one of the control method/driving method and the like in the present application or steps thereof is independently or cooperatively performed when the lighting device is operated or in an operating state.

In another embodiment of the present invention, a driving apparatus for use in a lighting apparatus is also provided, including a physical (physical) or virtual (virtual) apparatus/module for performing any one of the control methods/control methods and the like in the present application or steps thereof.

In another embodiment of the present invention, a driving circuit for use in a lighting device is also presented, comprising: a physical circuit module for performing any one of the control methods/control methods in the present application or steps therein.

Of course, it will be understood that: the control circuit for implementing the driving/controlling method of the light emitting load such as the LED array in some embodiments of the present invention implements the control of the LED array by the floating or common ground type switch unit, and therefore, the controlling method of the light emitting load by the driving circuit or the control circuit and the controlling of the switch unit by the control unit inside the driving device are corresponding to each other. The control unit in the control circuit in some embodiments of the invention may also be configured to perform the method of controlling the switching unit. Since the control methods and steps for the switch units have higher correspondence and similarity with the control methods and steps for the LED arrays in some embodiments, further description is omitted.

Alternatively, the control unit in some embodiments may be implemented as a hardware circuit module or a programmable control unit, processor.

In another embodiment of the present invention, a computer-readable storage medium storing one or more programs is also presented, the one or more programs comprising instructions, which when executed by a processor/control unit, cause the processor/control unit to perform any of the methods of driving/controlling in the present application or steps thereof.

In another embodiment of the invention, a driving circuit for use in a lighting device is also proposed, comprising a storage medium as proposed in some other embodiments of the invention, and a processor/control unit.

In another embodiment of the present invention, there is also provided a lighting device including: any one of the driver circuits or driver devices, as set forth in some other embodiments of the present invention, and the n LED arrays are coupled to and controlled by the driver circuit.

Optionally, the lighting device of some embodiments of the present invention further includes an electrical signal measurement unit and a dc power supply, the dc power supply including a rectification circuit configured to receive ac input power and rectify the ac input power to output to the n LED arrays; and an electrical signal measuring unit coupled in the lighting device and configured to measure an output of the rectifying circuit in a voltage or current manner.

Optionally, the n LED arrays are composed of one or at least two parallel LED strings, each LED string being composed of a plurality of LED groups connected in series, each LED group being composed of at least one LED in any electrical configuration.

Optionally, in the lighting device of some embodiments, the output terminal of the dc power supply is connected across the electrolytic capacitor. The capacitance of the electrolytic capacitor can be 1 muF, 20 muF, or exceed the interval, and the capacitance is selected according to the stability of the DC power supply and other factors.

Optionally, in the lighting device of some embodiments, the LED array in the first type bypass loop and the LED array in the second type bypass loop have the same conduction voltage drop.

Optionally, in the lighting device of some embodiments, n ≧ 2, conduction voltage drops of at least two of the n LED arrays (e.g., LED a and LED b) are the same, respectively connected in the first type bypass loop and the second type bypass loop that are alternately conducted. By alternately turning on the LEDs a and b to alternately establish the first type bypass loop and the second type bypass loop, since the conduction voltage drops of the first type bypass loop and the second type bypass loop are the same, the currents in the first type bypass loop and the second type bypass loop are also adjusted to be substantially the same, so that the overall power of the n LEDs can be maintained.

An embodiment of the present application also proposes a lighting device comprising a plurality of lighting loads, for example: a first lighting load and a second lighting load. Optionally, the first and second lighting loads have different stroboscopic characteristics. For example, the second load may be an LED array in the second bypass loop in some other embodiments, or an LED array in the second partial LED array; the first load may be an array of LEDs in the first bypass loop in some other embodiments, or an array of LEDs in the first portion of an array of LEDs. The first load and the second load each comprise one LED or a plurality of LEDs, wherein the plurality of LEDs may be connected in series and/or in parallel. Optionally, the first light emitting load and the second light emitting load may also be controlled by the driving circuit in other embodiments of the present application, so as to have different or relatively close stroboscopic characteristics, and further, by overlapping/interleaving, dispersing, and/or arranging in a central symmetry manner one or more LED arrays in the first light emitting load and one or more LED arrays in the second light emitting load in some other embodiments, the presence of the LED arrays in the light emitting loads at the higher stroboscopic portions is weakened, and the overall lighting effect and the stroboscopic characteristics of the lighting apparatus are improved.

An embodiment of the present application further provides a lighting device, including a first load and a second load, where the second load may be an LED array in a second bypass loop in some other embodiments, or an LED array in a second partial LED array; the first load may be an array of LEDs in the first bypass loop in some other embodiments, or an array of LEDs in the first portion of an array of LEDs. The first load and the second load are each configured as a lighting load and each comprise one LED or a plurality of LEDs, wherein the plurality of LEDs may be connected in series and/or in parallel.

Optionally, the lighting device may further include a control circuit or a driving circuit in other embodiments of the present application to drive the first load and the second load.

Optionally, the lighting device of some embodiments further comprises a substrate configured to carry a first load and a second load; the plurality of LEDs of the first load and the plurality of LEDs of the second load are at least partially staggered, or the plurality of LEDs of the first load and the plurality of LEDs of the second load at least partially overlap in outline area.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load are at least partially dispersed (e.g., discretely/dispersedly arranged) within an outline area of the plurality of LEDs of the first load; or

The plurality of LEDs of the second load are distributed and at least partially wrapped around the plurality of LEDs of the first load.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load are at least partially dispersed in an outline area of the plurality of LEDs of the first load.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load are integrally distributed within the outline area of the plurality of LEDs of the first load, for example, there is an overlap between the outline area of the second load and the outline area of the first load of 60% to 100%.

Optionally, in the lighting device of some embodiments, the outline area of the plurality of LEDs of the second load is smaller than the outline area of the plurality of LEDs of the first load by at least a ratio of 10% to 40%.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load and the plurality of LEDs of the first load are substantially symmetrically distributed around a center of an overall outline area of the first load and the second load.

Alternatively, in the lighting device of some embodiments, the plurality of LEDs of the second load and the plurality of LEDs of the first load are respectively arranged in central symmetry; and the centers of symmetry of the plurality of LEDs of the second load and the centers of symmetry of the plurality of LEDs of the first load substantially coincide.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load and/or the plurality of LEDs of the first load are arranged in a rectangular, circular, annular, curved/linear, symmetrical or asymmetrical radial shape, or the only LEDs in the second load are arranged substantially at the symmetrical center of the plurality of LEDs of the first load.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the first load are distributed within a rectangular, circular, annular, curved/linear, symmetrical or asymmetrical radial area on the substrate of the lighting device, and the plurality of LEDs of the second load are distributed within the plurality of LEDs of the first load.

Optionally, in the lighting device of some embodiments, the plurality of LEDs of the second load are distributed in a rectangular, circular, annular, curved/linear, symmetrical or asymmetrical radial shape; and the plurality of LED outline/coverage areas of the second load are comparable to or smaller than the plurality of LEDs outline/coverage areas of the first load in area. It should be understood that: the outline/coverage area herein refers to an envelope or outline area of the second load or the plurality of LEDs in the first load as a whole, or in a whole, rather than a sum of positions where only all of the individual LEDs are located, and also includes an area/space between the LEDs, and the like.

Alternatively, in the lighting device of some embodiments, the plurality of LEDs of the second load and the plurality of LEDs of the first load are adjacently disposed correspondingly or in pairs.

Another embodiment of the present invention provides a control circuit for controlling an electrical circuit including n LED groups connected in series with a dc power supply, the control circuit including a control unit and m sub-switching units; n is greater than or equal to 2, m is greater than or equal to 1, m is less than or equal to n, and m and n are integers;

the control unit is respectively connected with the m sub-switch units and controls the sub-switch units to be switched on or switched off; when the sub-switch unit is switched on, the corresponding LED group is bypassed, and when the sub-switch unit is switched off, the corresponding LED group is switched on;

when the output voltage of the direct current power supply is larger than or equal to the sum of the conduction voltage drops of the n LED groups, the control unit cuts off the m sub-switch units to form a main loop comprising the n LED groups and the direct current power supply;

when the output voltage of the direct current power supply is smaller than the sum of the conducting voltage drops of the n LED groups, the control unit conducts at least one sub-switch unit and cuts off the rest sub-switch units to form a sub-loop comprising the conducted sub-switch units, the conducted LED groups and the direct current power supply, and the sum of the conducting voltage drops of the conducted LED groups is smaller than the output voltage of the direct current power supply.

Optionally, the current flowing through the main loop is a main loop current, the current flowing through the sub-loop is a sub-loop current, and the control unit controls the sub-loop current to be larger than the main loop current.

Optionally, the control unit turns on at least one sub-switch unit and turns off the remaining sub-switch units to form a sub-loop including the turned-on sub-switch unit, the turned-on LED group, and the dc power supply, including:

when the number of the sub-loops is larger than or equal to two, the control unit controls the control circuit to operate at least two different sub-loops selected from all the sub-loops in a rotating mode according to a rotating frequency.

Optionally, the LED groups turned on in the at least two different subcircuits include all n LED groups.

Optionally, all the sub-loops are respectively sorted into a first-level sub-loop, a second-level sub-loop and a priority sub-loop from high to low according to the closeness degree of the sum of the voltage drops of the conducted LED groups and the output voltage of the direct-current power supply;

the at least two different sub-loops include at least a first level priority sub-loop and a second level priority sub-loop.

Optionally, the m sub-switch units are respectively connected in parallel to two ends of the corresponding m LED groups.

Optionally, the control circuit further comprises at least one current limiting device connected in series to the electrical circuit; the impedance of the current limiting device sets the main loop current flowing through the main loop and the sub loop current flowing through the sub loop.

Optionally, the control circuit further comprises at least one current limiting device connected in series to the electrical circuit; the impedance of the current limiting device sets the main loop current flowing through the main loop.

Optionally, the current limiting device and at least one LED group adjacent to the current limiting device form at least one serial branch; x sub-switch units of the m sub-switch units are respectively connected in parallel at two ends of the serial branch, and the other m-x sub-switch units are respectively connected in parallel at two ends of the corresponding LED group; x is greater than or equal to 1 and less than or equal to m, x being an integer.

Optionally, when at least one of the x sub-switch units connected in parallel to the two ends of the serial branch is turned on, the control unit sets a sub-loop current flowing through the sub-loop by controlling the on-resistance of the turned-on sub-switch unit;

when the x branch switch units connected in parallel at the two ends of the serial branch circuit are all cut off, the impedance of the current limiting device sets the branch circuit current flowing through the branch circuit.

Optionally, the control unit controls the sub-loop current and/or the main loop current to enable the variation range of the output power of the direct current power supply not to exceed a first preset threshold;

and/or the presence of a gas in the gas,

the control unit controls the sub-loop current and/or the main loop current to enable the difference value between the light emitting quantity of the conducted LED groups of the sub-loop and the light emitting quantities of the n LED groups of the main loop not to exceed a second preset threshold value.

Optionally, the current limiting device comprises at least one resistor.

Optionally, the current limiting device includes a field effect transistor and/or a transistor, and the impedance of the current limiting device is implemented by controlling the conduction degree of the field effect transistor and/or the transistor through the control unit.

Optionally, the sub-switching unit comprises a field effect transistor and/or a triode.

Optionally, when the dc power supply is a pulsating dc power supply, the rotation frequency is greater than a pulsating frequency of a pulsating dc voltage output by the pulsating dc power supply.

Optionally, at least a portion of the control circuitry is integrated in one or more integrated circuits.

The invention also provides a driving circuit, which comprises the control circuit and an electric loop, wherein the electric loop comprises a direct current power supply and n LED groups which are connected in series.

Optionally, the dc power supply comprises a steady dc power supply or a pulsating dc power supply.

Optionally, the pulsating dc power supply includes a rectifier and an energy storage capacitor, wherein an input end of the rectifier is connected to the ac power, and an output end of the rectifier is connected in parallel to the energy storage capacitor.

Optionally, at least a portion of the control circuit and at least a portion of the rectifier are integrated in one or more integrated circuits.

The invention also provides a control method, which is realized by using the drive circuit, and the control method comprises the following steps:

Judging the magnitude relation between the output voltage of the direct-current power supply and the sum of the conduction voltage drops of the n LED groups;

when the output voltage of the direct current power supply is larger than or equal to the sum of the conduction voltage drops of the n LED groups, turning off the m sub-switch units in the control circuit to form a main loop comprising the n LED groups and the direct current power supply;

when the output voltage of the direct current power supply is smaller than the sum of the conducting voltage drops of the n LED groups, at least one sub-switch unit is conducted, and the rest sub-switch units are cut off to form a sub-loop comprising the conducted sub-switch units, the conducted LED groups and the direct current power supply; the sum of the voltage drops of the conducted LED groups is less than the output voltage of the direct current power supply.

Optionally, the current flowing through the main loop is a main loop current, the current flowing through the sub loop is a sub loop current, and the sub loop current is greater than the main loop current.

Optionally, turning on at least one sub-switch unit and turning off the remaining sub-switch units to form a sub-loop including the turned-on sub-switch unit, the turned-on LED group, and the dc power supply, includes:

when the number of the sub-loops is larger than or equal to two, the driving circuit is controlled to rotate at least two different sub-loops selected from all the sub-loops at a rotation frequency.

Optionally, all the sub-loops are respectively sorted into a first-level sub-loop, a second-level sub-loop and a priority sub-loop from high to low according to the closeness degree of the sum of the voltage drops of the conducted LED groups and the output voltage of the direct-current power supply; the at least two different sub-loops include at least a first level priority sub-loop and a second level priority sub-loop.

Optionally, when the m sub-switch units are respectively connected in parallel to two ends of the corresponding m LED groups, and the electrical loop is further connected in series with at least one current limiting device:

the control method sets a main loop current flowing through the main loop and a sub-loop current flowing through the sub-loop through the impedance of the current limiting device.

Optionally, the electrical circuit is further connected in series with at least one current limiting device, and the current limiting device and at least one LED group adjacent to the current limiting device form at least one series branch; the control method sets the main loop current flowing through the main loop through the impedance of the current limiting device.

Optionally, when x of the m sub-switch units are respectively connected in parallel to two ends of the serial branch, and the remaining m-x sub-switch units are respectively connected in parallel to two ends of the corresponding LED group:

the control method also comprises the steps that when at least one of the x sub-switch units connected in parallel at two ends of the serial branch circuit is conducted, the sub-loop current flowing through the sub-loop is set by controlling the conducting impedance of the conducted sub-switch unit;

The control method also sets the sub-loop current flowing through the sub-loop through the impedance of the current limiting device when the x sub-switch units connected in parallel at the two ends of the serial branch circuit are all cut off;

wherein x is greater than or equal to 1 and less than or equal to m, x being an integer.

Optionally, the sub-loop current and/or the main loop current are/is controlled, so that the variation range of the output power of the direct current power supply does not exceed a first preset threshold;

and/or the presence of a gas in the gas,

and controlling the sub-loop current and/or the main loop current to enable the difference value between the light emitting quantity of the conducted LED groups of the sub-loop and the light emitting quantities of the n LED groups of the main loop not to exceed a second preset threshold value.

Optionally, when the current limiting device comprises a fet and/or a transistor, the impedance of the current limiting device is achieved by controlling the conduction level of the fet and/or the transistor.

Some embodiments of the present invention further provide a lighting device, which is manufactured by using the aforementioned driving circuit.

Optionally, the switching elements in some embodiments are transistors, such as DMOS transistors.

Some embodiments of the present invention also provide a control circuit for driving an at least partially series connected array of n LEDs supplied by a dc power supply, the control circuit comprising:

A control unit;

m switching units configured to respectively correspondingly couple m of the n LED arrays when the control circuit is applied to the n LED arrays, respective control terminals of the m switching units being respectively connected to the control unit, controlled by the control unit to bypass the corresponding LED arrays;

Optionally, in the control circuit of some embodiments of the present invention, the dc power supply is a pulsating dc power supply, and the control unit is configured to, in response to that the output voltage of the dc power supply (for example, the voltage value of a part of waveforms therein) is not enough to turn on the n LED arrays, control at least part of the m switching units to be turned off so that the corresponding part of LED arrays keeps on for a full period in at least one pulsating cycle of the dc power supply, or may also be understood as: and controlling at least partial conduction of the m switch units to bypass the corresponding LED array, so that the other part of the LED arrays can keep full-period conduction in at least one pulse period of the direct current power supply.

Optionally, in the control circuit of some embodiments of the present invention, the control unit includes:

an electrical signal measuring unit configured to determine whether an output voltage of the direct current power supply is sufficient to turn on the n LED arrays; and

And the signal processing unit is respectively connected with the electric signal measuring unit and the at least one switch unit and is operable to control the switch unit according to the comparison result of the electric signal measuring unit.

Optionally, in the control circuit of some embodiments of the present invention, the dc power supply outputs a pulsating voltage, and the control unit is configured to, in response to that the valley portion voltage/partial voltage is insufficient to turn on n LED arrays in a single pulsation cycle, gradually complete a transition from turning on n LED arrays to turning on partial LED arrays through a plurality of subsequent pulsation cycles.

Optionally, in the control circuit of some embodiments of the present invention, the electric signal measuring unit includes:

an integration unit operable to output an integration signal varying with time according to a determination result of whether the output voltage of the direct current power supply is sufficient to turn on the n LED arrays; and

a first comparator connected with the integration unit and configured to control the switching unit to operate in an on, off or regulated current mode based on a comparison result of the integration signal and the first electric signal,

the first electrical signal reflects/represents the output voltage of the direct current power supply or the voltage borne by the n LED arrays, or the first electrical signal has positive correlation/negative correlation with the pulsating direct current voltage or the voltage borne by the n LED arrays.

Optionally, in the control circuit of some embodiments of the present invention, the signal processing unit is configured to control the average value of the currents in the partial LED arrays and the average value of the currents in the n LED arrays to increase and decrease, respectively, in accordance with a change in the integrated signal over a plurality of pulsation periods.

Optionally, in the control circuit of some embodiments of the present invention, the signal processing unit is further configured to: coordinating the relative proportion of the on-time that n LED arrays are fully turned on to the on-time that some LED arrays are individually turned on, the relative proportions are sequentially decreased by a plurality of pulsing periods.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

In addition, it should be understood that: the circuit structure of some embodiments of the present invention may be changed or modified according to the principle of equivalent transformation of circuits. For example: current sources (also referred to as switching cells in some embodiments) are transformed into voltage sources, series configurations into parallel configurations, etc., to achieve more varied embodiments, but such variations and modifications are within the scope of the present disclosure. The applicant reserves the right to divide, actively modify, continue, and partially continue applications for these more varied variations.

The present invention has been described in relation to particular examples, which are intended in all respects to be illustrative rather than restrictive. Alternative examples will become apparent to those skilled in the art to which the present invention pertains without departing from its scope.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects set forth above, together with other advantages which are obvious and inherent to the system and method. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

The positive progress effects of the invention are as follows: when the output voltage of the direct current power supply is greater than or equal to the sum of the conduction voltage drops of all the LED groups, all the LED groups are conducted; and under the condition that the output voltage of the direct-current power supply is less than the sum of the conduction voltage drops of all the LED groups, the sub-loop is selected to conduct part of the LED groups in the circuit by controlling the conduction or the cut-off of the sub-switch unit. Furthermore, the change of the output power of the direct current power supply and/or the change of the LED luminous quantity do not exceed a preset threshold value by setting the sub-loop current to be larger than the main loop current, so that the change of the LED luminous quantity is reduced or even eliminated. Further, when the operating conditions of the plurality of sub-loops are met, the plurality of sub-loops are sorted into a first-level sub-loop, a second-level sub-loop and a higher-level priority sub-loop from high to low according to the proximity degree of the sum of voltage drops of the conducted LED groups and the output voltage of the direct-current power supply, and the driving circuit is controlled to operate at least two different sub-loops selected from the plurality of sub-loops in a rotating mode through a rotating frequency. The selected LED groups conducted in the sub-loop comprise all the LED groups, so that all the LED groups can be lightened. And meanwhile, the sub-loop current is controlled to be larger than the main loop current, and the sub-loop current of the low-priority sub-loop is controlled to be larger than the sub-loop current of the high-priority sub-loop, so that the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed a preset threshold when the main loop or any sub-loop runs. Furthermore, the change of the LED light emitting quantity does not exceed the preset threshold value, so that the light emitting stroboflash of the LED is reduced, and the harm to human eyes is reduced.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

FIG. 1 is a graph of a prior art LED parameter relationship;

FIG. 2 is a circuit diagram of a driving circuit in the prior art;

FIG. 3 is a circuit diagram of another driving circuit in the prior art;

FIG. 4 is a diagram illustrating a voltage-current relationship of a driving circuit in the prior art;

fig. 5 is a schematic circuit configuration diagram of a control circuit and a drive circuit according to embodiment 1 of the present invention;

fig. 6 is a schematic circuit diagram of a control circuit and a driving circuit when the current limiting device of embodiment 2 of the present invention is at least one of a field effect transistor and a triode;

fig. 7 is a schematic circuit diagram of a control circuit and a driving circuit when m is equal to n is equal to 3 according to embodiment 2 of the present invention;

fig. 8 is a schematic circuit diagram of a control circuit and a driving circuit in embodiment 2 of the present invention when n is 2 and m is 1;

fig. 9 is a schematic circuit diagram of a control circuit and a driving circuit when the current limiting device of embodiment 2 of the present invention is a resistor;

Fig. 10 is a schematic circuit configuration diagram of a control circuit and a drive circuit according to embodiment 3 of the present invention;

fig. 11 is a schematic circuit diagram of a control circuit and a driving circuit in embodiment 3 of the present invention when n is 2 and m is 1;

FIG. 12 is a flowchart of a control method according to embodiment 4 of the present invention;

FIG. 13 is a flowchart of a control method according to embodiment 5 of the present invention;

fig. 14 is a flowchart of a control method of a first circuit configuration according to embodiment 6 of the present invention;

fig. 15 is a flowchart of a control method of a second circuit configuration according to embodiment 6 of the present invention;

FIG. 16 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source operating at the pulsating DC voltage in another embodiment of the present invention;

FIG. 17 is a current waveform diagram of a switch unit or a corresponding LED array in a transition state of switching according to another embodiment of the present invention;

fig. 18 is a schematic circuit configuration diagram of a current source in a driving circuit according to another embodiment of the present invention;

fig. 19A is a functional block diagram (function block diagram) of a control circuit in a driving circuit according to another embodiment of the present invention;

FIG. 19B is a functional block diagram (function block diagram) of a control circuit with a timer according to another embodiment of the present invention;

FIG. 20 is an electrical waveform of an alternatively conducting switch unit or corresponding LED array in another embodiment of the present invention;

FIG. 21 is a functional block diagram of a driver circuit with a control circuit according to another embodiment of the present invention;

FIG. 22 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source that is alternately turned on at high frequency under the pulsating DC voltage in accordance with another embodiment of the present invention;

FIG. 23 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source operating at the pulsating DC voltage in another embodiment of the present invention;

FIG. 24 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source that is alternately turned on at the pulsating DC voltage in accordance with another embodiment of the present invention;

FIG. 25 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source that is alternately turned on at the pulsating DC voltage in accordance with another embodiment of the present invention;

FIG. 26 is a diagram of a pulsating DC voltage waveform and current regulation waveform of a switching unit/current source that is alternately turned on at the pulsating DC voltage in accordance with another embodiment of the present invention;

FIG. 27 is a functional block diagram of a driving circuit and a lighting device capable of operating the control method in other embodiments of the present invention in another embodiment of the present invention;

FIGS. 27 a-27 c are schematic diagrams of various variations of an LED array of FIG. 27 and other embodiments of the invention;

FIG. 28 is a schematic diagram of two LED sets with different stroboscopic characteristics of the n LEDs according to another embodiment of the present invention;

FIG. 29 is a schematic diagram of two LED groups with different stroboscopic characteristics among n LEDs according to another embodiment of the present invention;

FIG. 30 is a schematic diagram of two LED sets with different stroboscopic characteristics of n LEDs according to another embodiment of the present invention;

FIG. 31 is a schematic diagram of a switch unit/current source with a current programming interface reserved inside for receiving an external resistor according to an embodiment of the present invention;

FIG. 32 is a schematic diagram of a switch unit/current source with a current programming interface reserved inside for receiving an external resistor according to an embodiment of the present invention;

FIG. 33 is a diagram of a package frame structure adopted by the driving circuit according to an embodiment of the invention;

FIG. 34 is a schematic diagram of voltages at different levels provided by a DC power supply for powering a lighting load and a driving circuit thereof and corresponding regulated currents in the lighting load according to an embodiment of the present invention;

FIG. 35 is a waveform illustrating a first voltage interval during which two LED arrays are alternately turned on;

FIGS. 36a and 36b are functional block diagrams of two hardware circuits of a driving circuit/lighting device according to another embodiment of the present invention;

FIG. 37 is a schematic diagram of two LED sets with different stroboscopic characteristics of n LEDs according to another embodiment of the present invention;

fig. 38 is a schematic circuit diagram of a driving circuit and a control circuit when n is 2, m is 2, and x is 1 according to another embodiment of the present invention;

fig. 39 is a schematic circuit diagram of a driving circuit and a control circuit when n is 2, m is 2, and x is 1 according to another embodiment of the present invention;

fig. 40 is a schematic circuit diagram of a control circuit and a driving circuit when m is equal to n is equal to 3 according to another embodiment of the present invention;

FIG. 41 is a schematic diagram of a control unit in the control circuit according to another embodiment of the present invention;

FIG. 42A is a schematic diagram of a control unit in a control circuit according to another embodiment of the present invention;

FIG. 42B is a diagram illustrating a control unit of the control circuit according to another embodiment of the present invention;

FIG. 43 is a waveform diagram of the current change during a ramp transition for the driving circuit shown in FIG. 11;

FIG. 44 is a waveform of another current change during a ramp transition for the drive circuit shown in FIG. 11;

FIG. 45 is a schematic circuit diagram of a control circuit and a driving circuit according to another embodiment of the present invention;

FIG. 46 is a waveform diagram of the current change during a ramp transition for the drive circuit shown in FIG. 45;

FIG. 47 is another waveform of current change during a ramp transition for the drive circuit shown in FIG. 45;

fig. 48 is a waveform diagram of a current change during a gradation transition of the driving circuit shown in fig. 27.

Detailed Description

Reference will now be made in detail to the embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of various described embodiments. It will be apparent, however, to one skilled in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail as not to unnecessarily obscure aspects of the embodiments.

The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms "comprises," "comprising," "includes," and/or "including," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

As used herein, the term "if" is optionally to be interpreted to mean "when.. or" ("where" or "upon") or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrase "if it is determined.. -." or "if [ the stated condition or event ] is detected" is optionally to be construed to mean "upon determining. -. or" in response to determining. -. or "upon detecting [ the stated condition or event ]" or "in response to detecting [ the stated condition or event ]", depending on the context.

The word "by" as used in this application may be construed as "by" (by), "by" (by virtual of) or "by" (by means of) depending on the context. The words "if", as used herein, may be interpreted as "at … …" or "at … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, "when … …" or "when … …" in some embodiments may also be interpreted as conditional assumptions such as "if", "like", etc., depending on context. Similarly, the phrases "if (a stated condition or event)", "if determined" or "if detected (a stated condition or event)" may be construed as "when determined" or "in response to a determination" or "when detected (a stated condition or event)", depending on the context. Similarly, the phrase "in response to (a stated condition or event)" in some embodiments may be interpreted as "in response to detecting (a stated condition or event)" or "in response to detecting (a stated condition or event)", depending on the context.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, a first may also be termed a second, and vice versa, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at …" or "when …" or "in response to a determination", depending on the context.

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.

LED

As a general light emitting device, an LED, that is, a light emitting diode, is widely used in the field of lighting, and it is common to fix an LED chip on a base or a frame, for example, under the package names 2835, 3030, and the like. In addition to the one LED chip or a plurality of LED chips connected in series, there are also packages using COB method, that is, a plurality of LED chips are directly attached to a metal substrate to be connected.

LED array

To accommodate different lighting needs, multiple LEDs are often used in combination to build a diverse lighting scene. When a plurality of LEDs are used in combination, the plurality of LEDs may be divided into a plurality of LED arrays (which may also be referred to as LED groups or LED segments) according to one or more combinations of differences in arrangement positions in space, differences in functions realized in an illumination scene, or differences in connection positions in the same circuit.

When the division logic of the plurality of LEDs is changed, the plurality of LED arrays formed by the division thereof are changed accordingly.

Taking the example of dividing the LED arrays according to the difference of the connection positions of the LEDs in the same circuit, each LED array includes at least one LED, and when a plurality of LEDs are included in one LED array, the plurality of LEDs may be directly connected in parallel, in series, or in a combination of series and parallel, or indirectly connected through another device (e.g., a resistor).

Stroboscopic device

The lighting device may produce flickering light, which may cause serious illnesses such as headaches, visual disturbances, or in extreme cases, seizure. Even if the glints are not perceptible, for example at a frequency of 100HZ, your eyes may not be consciously looking at it, but the brain may still be able to detect and react to it with negative consequences and have an impact on operations that are very dependent on lighting effects, such as interfering with camera shots, often rolling shutter images displayed on a cell phone screen.

Since the grid (or utility) is a 50/60HZ periodically fluctuating ac voltage, the corresponding energy frequency is 100/120HZ, which makes almost all types of lamps susceptible to periodic flicker, including incandescent, halogen, and even LED light bulbs. But the effect of each light is different. Where the LED responds faster to current changes, so flicker is more pronounced.

Commonly used terms characterizing the degree of Flicker include strobe depth, strobe percentage, fluctuation depth, strobe index, etc., one measure of which is the amplitude of the fluctuation of the periodic light, e.g., strobe depth (Percent Flicker) equals the difference between the maximum and minimum light output over a switching period divided by the sum of the maximum and minimum light output, and strobe index (Flicker index) equals the amount of excess average light output over a switching period divided by the total light output. The lower the strobe depth and the strobe index, the smaller the light fluctuation or resulting strobe effect; another measure is the frequency of light fluctuations, which are generally more likely to cause discomfort and affect operation at lower frequencies (e.g. 100HZ), and somewhat better, e.g. regulations that do not limit fluctuations above 3125HZ, i.e. high frequency exemptions, because to some extent they have substantially no effect on the environment and the user.

For convenience of description, in some embodiments of the present disclosure, the periodic flashing of the light may be referred to as stroboscopic, and the stroboscopic with the frequency less than 3125HZ is divided into low-frequency stroboscopic and the stroboscopic with the frequency greater than 3125HZ is divided into high-frequency stroboscopic.

Technical prejudice

The technical bias means the understanding of the technical problem, which is generally existed in a certain technical field in a certain period of time and deviates from the objective fact, and guides people to avoid considering the possibility of other aspects and hinders people to research and develop the technical field. The invention overcomes the technical bias of the technicians in the field, and adopts the technical means abandoned by people due to the technical bias: the number of the conducted LEDs is changed and/or the current flowing through the conducted LEDs is adjusted, so that the technical problem that the lighting device generates low-frequency stroboflash is solved to a certain extent.

Lighting devices are powered by the ac grid (mains), typically lighting devices are required to have low frequency stroboscopic, and lighting devices of greater power (e.g. greater than 25W) are required to have higher power factor (or lower input current harmonics), which requires different schemes to be deployed, common approaches to lighting devices driven by linearly regulated current sources (linear current sources) include:

the first means is as follows: comprising a single segment (or single) LED array with an energy storage capacitor connected in parallel at the ac rectified output to produce a smooth pulsating dc voltage, as shown in fig. 2. When the grid voltage is a rated value and the pulsating direct current voltage is greater than the conduction voltage drop of the LED, the current flowing through the LED is controlled by the current source to be a stable value, the light emission is stable and has no stroboflash, however, when the grid voltage is low, periodically, the pulsating direct current voltage is smaller than the conduction voltage drop of the LED in a part of time interval, the current flowing through the LED is reduced even to be zero, and as shown in fig. 3, low-frequency stroboflash is generated. Thus, the disadvantages of a lighting device comprising a single segment LED array are: the conduction voltage drop of the configured LED array cannot be too high, otherwise the adaptive capacity of the LED array to the voltage fluctuation of an alternating current power grid can be influenced, and further, the LED array cannot emit light enough to generate low-frequency stroboflash when the voltage of the power grid is lower; when the conduction voltage drop of the configured LED array is low, the efficiency of the lighting device is low; that is, in the prior art, the lighting device including the single-segment LED array cannot take into account the reduction of the low-frequency stroboscopic, the improvement of the efficiency, and the adaptation to the wide-range mains supply fluctuation.

The second means: the LED array comprises a plurality of sections (or a plurality of sections) of LED arrays, and an energy storage capacitor is not connected in parallel at the output end of the AC rectifier. The principle is as follows: in response to a gradual rise of the ac rectified voltage (instantaneous value), the LED arrays at higher potentials in the loop are sequentially turned on, so that the turn-on voltage drop of the LED arrays that are turned on gradually increases, and in response to a gradual fall of the ac rectified voltage (instantaneous value), the LED arrays at lower potentials in the loop are sequentially bypassed, so that the turn-on voltage drop of the corresponding LED arrays gradually falls, and the current of the LED arrays that are turned on is adjusted to be positively correlated with the ac rectified voltage value corresponding to the ac rectified voltage (instantaneous value), which is advantageous for achieving a higher power factor and a lower current harmonic. Because the output end of the rectifier is not provided with the parallel energy storage capacitor, all the LED arrays do not have current to flow at or near the periodic zero crossing point moment of the alternating current, and low-frequency stroboflash is generated.

The third means: and on the basis of the second means, an energy storage capacitor is connected in parallel with the alternating current rectification output end. If the capacity of the energy storage capacitor is large enough, when the commercial power is stable, the change amplitude of the pulsating direct current voltage output by rectification is small, all the multiple sections of LEDs are conducted, and stroboflash is basically avoided. However, when the utility power is reduced to a certain range, it is inevitable that a part of the LEDs is turned on and another part of the LEDs is turned off periodically, that is, when the grid voltage is low, a low-frequency strobe is generated. Similarly, the conduction voltage drop of the configured LED array cannot be too high, which may affect the adaptability of the LED array to ac power grid voltage fluctuation, and further cause insufficient light emission to generate low-frequency stroboflash when the power grid voltage is low; when the conduction voltage drop of the configured LED array is low, the efficiency of the lighting device is low; that is, in the prior art, the lighting device including the multi-segment LED array cannot take into account the reduction of the low-frequency stroboflash, the improvement of the efficiency, and the adaptation to the wide-range commercial power fluctuation.

As shown in fig. 3, it is also known to those skilled in the art to detect the average value of the rectified voltage through the resistor R1, the resistor R2, the capacitor CF or the like to control the power flowing through the LED to decrease with the increase of the input voltage, and trade the light emitting amount of the LED for the relatively stable input power, however, the resistor R1 inevitably introduces more or less pulsating components of the rectified voltage, which causes the current of the LED to vary with the pulsating period of the rectified voltage, resulting in low frequency strobing, and on the other hand, when the pulsating dc voltage of the rectified output is periodically low enough to drive the LED array, the problem of low frequency strobing still cannot be solved.

The power factor of the first means is lower, but the low-frequency stroboscopic effect is lower under the rated voltage of the power grid; the second approach has a higher power factor but low frequency stroboscopic; the third means is a compromise result of the first means and the second means, and in combination with the constant power means as shown in fig. 3, this brings a habitual thinking to those skilled in the art: for linear current source driven lighting devices, the purpose of varying the LED drive current is to achieve a higher power factor or lower current harmonics, or to achieve a constant power at the ac mains input, while the latter sacrifices the amount of light emitted by the lighting device more or less and increases the low frequency stroboscopic.

In particular, it is known that changing the current of an LED changes the amount of light emitted by the LED, which in turn causes stroboscopic effects. This is certainly true on the premise that the LED on is not changed, and therefore, those skilled in the art always tend to reduce the stroboflash by controlling the current of the LED to be constant. The commonly used means are: the method is characterized in that a large-capacity energy storage capacitor and a stable current source are connected in series with the LED in parallel, such as the first means and the third means, or the LED with lower conduction voltage drop is used, and the improvement of low-frequency stroboflash is obtained by compromising the energy conversion efficiency. One of ordinary skill in the art ignores an important fact: the lighting device is a luminary whose luminous effect is generated by all the luminous sources (single LED) inside. The technical prejudice and the limited innovation that the skilled person only focuses on the strobing of the fixed/localized luminous sources, rather than the strobing of the entire luminous body.

Furthermore, it is also always desirable by those skilled in the art to: it is also a technical prejudice that the current of the LEDs inside the lighting device, which is driven by a linear current source, is as stable and as ripple-free as possible. Strobing of the lighting device is due to periodic light fluctuations, not to high or low luminous flux, and unacceptable strobing is also strobing only in a certain frequency range, not in the full frequency range. The improvement of the lighting effect of the lighting device is usually only required to improve the stroboflash in a specific frequency range.

Thus, it is generally accepted by those skilled in the art that: for a lighting device powered by mains supply, the linear current source driving scheme cannot give consideration to three indexes of energy conversion efficiency, light emitting stroboflash and wide-range mains supply fluctuation adaptation. This general recognition limits those skilled in the art to innovating linear current source drive schemes.

And, increasingly sophisticated and cost-effective switching power supply solutions for driving lighting devices are known to have many advantages over linear current sources in terms of technical maturity, versatility, flexibility, even insulation safety, etc., which also limits the power of those skilled in the art to make innovations to linear current sources.

Moreover, generally, the stroboscopic test for lighting devices in the field is performed at a rated voltage, and the actual grid voltage fluctuates within a certain range, which leads those skilled in the art to further neglect the potential problem in such a practical application: strobing of the lighting device may frequently occur in real mains application scenarios.

Based on the above habitual cognition and technical prejudices, the development and innovation of linear current sources are limited. At present, no prior art proposes: the low-frequency stroboscopic of the lighting device is improved by changing the number of the conducted LEDs and adjusting the current of the conducted LEDs. Because this is generally not believed to be beneficial in improving strobing, those skilled in the art have no motivation to improve low frequency strobing by adjusting the current.

When recognizing the above-mentioned potential needs, the inventor of the present invention overcomes the technical bias of those skilled in the art, and adopts the technical means of adjusting the current and adjusting the LED array to be turned on, which is abandoned by the technical bias, thereby solving the technical problem of eliminating or reducing the stroboflash of the lighting devices such as LEDs, and improving the energy conversion efficiency and the capability of adapting to the grid voltage variation.

The inventors of the present invention have first realized that by bypassing a part of the LEDs to accommodate a wide range of mains fluctuations, then realized that by alternately/alternatingly bypassing different LED loops by the switching unit, all LEDs can be lit up during one ac rectified voltage period to improve the lighting effect of the lighting device, and then realized that by controlling the current in the loop containing the LED array with less conduction to be larger, the power can be maintained substantially constant, and/or, when powered by a mains rectified pulsating dc voltage, by controlling the driving circuit to continuously run in one fixed loop or in at least two bypass loops with alternating/alternating conduction at a certain frequency during at least one pulsating period, and to control the gradual transition between the different loops during mains fluctuations to reduce or eliminate low frequency strobes and improve the lighting effect, and then further through trial and error, determining that the low-frequency stroboflash is remarkably effective to be improved, and further improving the illumination effect through specific and limited arrangement of the LED arrays on the positions, finally forming the complete concept of the invention, and the switch unit is structurally configured to be floating and common ground so as to be easily implemented into a whole integrated circuit package body, and a package frame of a double-base island is purposefully designed.

Alternatively, one aspect of the invention is contemplated as follows: firstly, a part of LEDs can be bypassed to adapt to wide-range mains supply fluctuation; secondly, different LED loops are bypassed alternately by the switch unit, so that all LEDs can be lightened in an alternating current rectification voltage period to improve the light emitting effect of the lighting device; thirdly, the power is kept constant by controlling the current of the loop containing fewer conducted LED arrays to be larger, and/or, when the power is supplied by the pulsating direct-current voltage rectified by the mains supply, the driving circuit is controlled to continuously run in a fixed loop or run in at least two bypass loops which are alternatively/alternately conducted at a certain frequency in at least one pulsating period, and the gradual change conversion between different loops is controlled when the mains supply fluctuates, so that the low-frequency stroboflash is reduced or eliminated, and the lighting effect is improved; fourthly, the effect of improving the low-frequency stroboflash is obviously determined through repeated tests; fifthly, the low-frequency stroboscopic is further improved by carrying out specific and restrictive arrangement on the LED arrays on the positions; sixthly, the switch unit is configured to be both floating ground and common ground on the electrical structure, so as to be easily implemented into a whole integrated circuit package; and seventhly, designing a double-base island packaging frame corresponding to the structures of the floating ground and the common ground.

The driving circuit in some embodiments of the present invention allows a power supply voltage of a dc power supply or the like to be higher or not higher than a conduction voltage drop of the n LED arrays, when the power supply voltage is higher than the conduction voltage drop of the LEDs, all the LED currents are stably controlled to a small value by the current source connected in series to the LED main loop, when the power supply voltage is not higher than the conduction voltage drop of the LEDs, a part of the LEDs are bypassed, and the current of the other remaining part of the LEDs is controlled to a large value, the more the LEDs bypassed, the larger the current of the other remaining part of the LEDs, and a proper value is configured according to the number of the other remaining part of the LEDs, so that a larger approximately constant light emitting amount of the LEDs can be obtained, and/or, when the power supply is performed by a pulsating dc voltage rectified by a mains supply, the driving circuit is controlled to continuously operate in the main loop for at least one pulsating period corresponding to a mains voltage value or a mains voltage range, or a fixed bypass loop, or at least two fixed bypass loops which are alternatively/alternatively conducted at a certain frequency, and when the commercial power voltage value or the commercial power voltage range is changed and needs to be converted into different loops, the conversion process between the different loops is controlled to be gradual conversion, so that the low-frequency stroboflash is reduced or eliminated, and the luminous effect is improved.

When the supply voltage changes periodically, for example, the pulsating dc voltage output from the ac power supply after rectification and filtering, the possible operation modes are:

1) the pulsating direct current voltage is always greater than the conduction voltage drop of the n LED arrays, and the current of the LED arrays is always controlled to operate at a small value, so that the power or luminous flux is basically constant, and low-frequency stroboflash is avoided;

2) the pulsating dc voltage cannot make n LED arrays all on, i.e.: the power supply voltage is less than the conduction voltage drop when the n LED arrays are all conducted, but is always greater than the conduction voltage drop of the LED array which is not bypassed in the other part left after one part of the LED array is bypassed, the current of the other part left is always controlled to be operated at a large value, the power or luminous flux is kept basically constant, and the power or the luminous flux is basically the same as that in 1), and low-frequency stroboflash is basically avoided in the switching process among a plurality of different loops.

3) The supply voltage is periodically changed according to 1) and 2) above, the current of the n LED arrays is controlled to be a small value when the main loop is operated, and the current of the other part of the LED arrays remaining after bypassing a part of the LED arrays is controlled to be a large value when the other part of the LED arrays is turned on to operate, and the driving circuit of the related embodiment can control the supply of the substantially constant electric power to the n LED arrays, so that the n LED arrays have stable luminous flux. In this case, the light emission amount of the single LED array periodically changes, but the total light emission amount of the n LEDs does not change. For a common user of the lighting device controlled by the related driving circuit, when the user or the test instrument is close to the LED, the light emitting stroboscopic of the single LED unit may be sensed; as the user or test instrument moves farther from the LED array, the amount of light emitted by the entire LED is perceived more and more as a whole, and thus the perceived strobe is lower and lower. Experiments prove that when the mains voltage is reduced by 10%, the low-frequency stroboscopic depth of practical tests is less than 5%, compared with the traditional scheme, the low-frequency stroboscopic device has an obvious improvement effect and can meet most of lighting requirements.

4) When the minimum value of the pulsating direct current voltage supplied by the mains supply in at least one pulsating period is always larger than the conduction voltage drop of the n LED arrays, the driving circuit is controlled to operate in the main loop, and when the minimum value of the pulsating direct current voltage supplied by the mains supply is not enough to drive the conduction voltage drop of the n LED arrays, the driving circuit is controlled to continuously operate in the corresponding bypass loop or at least two bypass loops alternately/alternately conducted at a certain frequency in at least one pulsating period, so that low-frequency stroboflash can be eliminated. Experiments prove that: the product designed by the embodiment has the advantages that when the commercial power voltage is reduced by 10%, the low-frequency strobe depth of the practical test is less than 2.5%, compared with the traditional scheme, the low-frequency strobe depth has an obvious improvement effect, and most of lighting requirements can be met.

5) Because the bypassed LED array has larger variation of the luminous brightness compared with the bypassed LED array, in order to reduce the influence of the bypassed LED array on the whole luminous of the lighting device, the LED array which is possibly bypassed is distributed or staggered with other LED arrays which are not bypassed, so that the low-frequency stroboflash of the lighting device can be further reduced or eliminated, and the luminous effect is improved.

Based in part on these technical prejudices presented to the person skilled in the art, and through extensive analytical studies, the inventors propose various embodiments of the invention with a significant improvement.

Example one

The present embodiment provides a control circuit and a driving circuit, as shown in fig. 5, the control circuit 1 is configured to control an electrical loop formed by connecting a dc power supply U and n LED groups LEDs 1 … LEDn in series, the control circuit 1 includes a control unit D1 and m sub-switching units Q1 … Qm; wherein n is an integer greater than or equal to 2, and m is an integer greater than or equal to 1 and less than or equal to n. The driving circuit 2 includes a control circuit 1 and U, n LED groups, LEDs 1 … LEDn, of a dc power supply.

The LED group LEDs 1 … LEDn are LED combinations formed by connecting 1 or more LEDs in series or in parallel respectively; the sub-switch units Q1 … Qm respectively correspond to one LED group, when the sub-switch units are turned on, the corresponding LED group is bypassed, and when the sub-switch units are turned off, the corresponding LED group is turned on to turn on or off the corresponding LED group, in fig. 5, the sub-switch unit Q1 corresponds to the LED1, the sub-switch unit Q2 corresponds to the LED2, and the sub-switch unit Qm corresponds to the LEDn; the control units D1 are respectively connected with the m sub-switch units and control the on/off of the sub-switch unit Q1 … Qm.

The corresponding relationship between each sub-switch unit and the LED group is not limited to fig. 5, and the numbers of m and n may be equal, such as a schematic circuit structure diagram of the control circuit 1 and the driving circuit 2 when m is equal to n is equal to 3 shown in fig. 7; the numbers of m and n may not be equal, as shown in fig. 8, and only two ends of the LED2 correspond to one sub-switch unit Q1.

The foregoing series connection includes direct connection through a wire or indirect connection through any device, such as indirect connection through a resistor, and the order of connection is not limited, and the following series connections all have the same meaning.

The sub-switching unit Q1 … Qm includes a field effect transistor and/or a triode. The dc power supply includes a steady dc power supply or a pulsating dc power supply, and the steady dc power supply refers to a non-periodic fluctuating dc power supply such as a dc power supply generated by a battery output or a high frequency switching power supply. The pulsating direct current power supply refers to a periodically fluctuating direct current power supply, such as a power supply powered by alternating current rectification or a power supply converted by other conversion modes; the rectification method includes full-bridge rectification, full-wave rectification, half-wave rectification, or voltage-doubling rectification, for example, the pulsating dc power supply shown in fig. 2 includes a commercial power, a rectifier and at least one capacitor, the input end of the rectifier is connected to the commercial power, the capacitor is connected in parallel to both ends of the dc output end of the rectifier, and the dc output end of the rectifier outputs a pulsating dc voltage with a pulsating period to supply power.

When the output voltage of the direct current power supply U is greater than or equal to the sum of the conduction voltage drops of the n LED group LEDs 1 … LEDn, the control unit D1 turns off the m sub-switch units Q1 … Qm to form a main loop including the n LED group LEDs 1 … LEDn and the direct current power supply U, and the n LED group LEDs 1 … LEDn in the main loop are all turned on.

When the output voltage of the direct current power supply U is less than the sum of the conduction voltage drops of the n LED groups LED1 … LEDn, the control unit D1 turns on at least one sub-switch unit, and turns off the remaining sub-switch units to form a sub-loop including the direct current power supply U, the LED groups that are turned on, and the sub-switch units that are turned on, the LED groups that are turned on include the LED group corresponding to the sub-switch unit that is turned off and the LED group that is not always turned on corresponding to the sub-switch unit, and the sum of the conduction voltage drops of the LED groups that are turned on is less than the output voltage of the direct current power supply U.

In this embodiment, when the output voltage of the dc power supply is greater than or equal to the sum of the conduction voltage drops of all the LED groups, all the LED groups are turned on; under the condition that the output voltage of the direct-current power supply is smaller than the sum of the conduction voltage drops of all the LED groups, the sub-switch units are controlled to be switched on or off, the sub-loop is selected to enable part of the LED groups in the circuit to be switched on, and the condition that the LED lamp cannot be lightened when the output voltage is smaller than the sum of the conduction voltage drops of all the LED groups does not occur.

Example two

The present embodiment is further optimized on the basis of the first embodiment, and provides a control circuit and a driving circuit, where the control circuit 1 includes a current limiting device Q0 in addition to a control unit D1 and m sub-switch units Q1 … Qm, and the current limiting device Q0 is connected in series to an electrical loop formed by a dc power supply U and n LED groups LED1 … LEDn connected in series; wherein n is an integer greater than or equal to 2, and m is an integer greater than or equal to 1 and less than or equal to n. The driving circuit 2 includes a control circuit 1 and U, n LED groups, LEDs 1 … LEDn, of a dc power supply.

The current limiting device Q0 may be a resistor, a field effect transistor and/or a triode, and may be disposed at a desired position in the control circuit 1 and the driving circuit 2. When the current limiting device Q0 is a field effect transistor and/or a triode, the specific circuit structure is shown in fig. 6.

When the output voltage of the dc power supply U is greater than or equal to the sum of the turn-on voltage drops of the n LED group LEDs 1 … LEDn, the control unit D1 turns off the m sub-switching units Q1 … Qm to form a main circuit including the current limiting device Q0, the n LED group LEDs 1 … LEDn and the dc power supply U, and the n LED group LEDs 1 … LEDn in the main circuit are all turned on. The control unit D1 is connected to the current limiting device Q0, and sets the main loop current flowing through the main loop by controlling the on-resistance of the current limiting device Q0.

The sub-loops are sequentially sorted into a multi-level priority sub-loop according to the closeness degree of the sum of the voltage drops of the conducted LED groups and the output voltage of the DC power supply U from high to low, for example, the first-level priority sub-loop and the second-level priority sub-loop … sequentially represent the multi-level priority sub-loop in which the closeness degree of the sum of the voltage drops of the conducted LED groups and the output voltage is sorted from high to low, and are also the multi-level priority sub-loop in which the efficiency is sorted from high to low in the process of converting the energy of the DC power supply U in the loop into the energy of the LED groups. The control unit D1 also controls the drive circuit 2 to rotate at least two different sub-loops selected from the plurality of sub-loops at a rotation frequency. The LED groups conducted in the at least two different sub-loops comprise all n LED groups 1 … LEDn, and all the LED groups can be conducted in one rotation period; and the at least two different sub-loops at least comprise a first-level priority sub-loop and a second-level priority sub-loop, so that the operation efficiency of the driving circuit 2 is optimized.

The control unit D1 controls the sub-loop current flowing through the sub-loop, and controls the sub-loop current to be greater than the main loop current, and the sub-loop current of the low-level priority sub-loop to be greater than the sub-loop current of the high-level priority sub-loop, so that the variation range of the output power of the dc power supply U does not exceed the first preset threshold, that is, when the driving circuit 2 operates in the main loop, the first-level priority sub-loop, the second-level priority sub-loop …, or any other sub-loop, the variation range of the sum of the power of the LED group turned on in the circuit, the power of the current-limiting device Q0, and the power of the sub-switching unit turned on does not exceed the first preset threshold, that is, the power drawn by each sub-loop current from the dc power supply U is as close as possible to the power drawn by the main loop current from the dc power supply U, and the power variation of the driving circuit 2 is reduced or eliminated. The smaller the value of the first preset threshold value is, the better the effect is.

Or, the control unit D1 controls the sub-loop current to be larger than the main loop current, and the sub-loop current of the low-level priority sub-loop to be larger than the sub-loop current of the high-level priority sub-loop, so that the difference between the light emission amount of the LED groups conducted in the sub-loop and the light emission amounts of the n LED groups of the main loop does not exceed the second preset threshold, and thus, the variation of the light emission luminance of the LED units in the driving circuit 2 under different dc voltages can be reduced or even eliminated; when the direct current power supply U is a pulsating direct current power supply, stroboflash is reduced or even eliminated. The smaller the value of the second preset threshold value is, the better the effect is.

When the direct current power supply is a pulsating direct current power supply, the periodically fluctuating direct current voltage causes the periodic operation and stop of the sub-loops or the periodic switching between different sub-loops. The control unit D1 controls the rotation frequency of the rotation operation of different sub-loops, so that the number of times that each LED group that is turned on alternately is changed in different unit time is as constant as possible, the light emission amount of the corresponding LED group in different unit time is approximately constant, which is beneficial to the stability of the light emission amount of the LED, the larger the rotation frequency is, the better the effect is, and when the rotation frequency exceeds the audio frequency, the mechanical vibration sound caused by the rotation frequency is not easily perceived by human hearing.

It should be added that the first-level priority sub-loop, the second-level priority sub-loop … or any other priority sub-loop merely represents the order of the sum of the voltage drops of the LED groups that are turned on and included in the sub-loop and the closeness of the output voltage of the dc power supply U under a specific output voltage of the dc power supply, and is not specific to a specific sub-loop, and the priorities of the sub-loops may be different under different dc voltages.

The following describes a specific case of the present embodiment by taking a driving circuit when n is 3 and m is 3 as an example, and a schematic circuit configuration is shown in fig. 7.

For convenience of explaining the idea of the embodiment of fig. 7, assuming that the unit power light emission amount of each LED group is the same under the same driving current, the conduction voltage drops of the three LED groups LED1, LED2 and LED3 are V1, V2 and V3, respectively, wherein V1 is greater than or equal to V2 is greater than or equal to V3, and V2+ V3 is greater than or equal to V1; the output voltage of the dc power supply U is V.

When V is greater than or equal to V1+ V2+ V3, the control unit D1 controls all the 3 sub-switch units to be turned off, and the control unit D1 controls the on-impedance of the current limiting device Q0 to turn on the main circuit formed by the dc power supply U, the first LED group LED1, the second LED group LED2, the third LED group LED3 and the current limiting device Q0 with the main circuit current IM, at this time, the output power PM of the dc power supply is V × IM, the light emission quantity LM of the LED group is IM × (V1+ V2+ V3) × KM, and KM is the unit power light emission quantity corresponding to the LED group when driving the current IM.

When V < V1+ V2+ V3, the present embodiment has six different sub-loops, i.e. the first to sixth sub-loops, according to different on/off states of the sub-switch units, as shown in table 1:

TABLE 1

A first branch loop: the first sub-switch unit Q1 and the second sub-switch unit Q2 are turned off, the third sub-switch unit Q3 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a first sub-loop composed of the dc power supply U, the first LED group LED1, the second LED group LED2, the third sub-switch unit Q3 and the current limiting device Q0 by a first current I1, the power P1 of the first sub-loop is V × I1, the light emitting amount L1 of the LED group is (V1+ V2) × I1 × K1, and K1 is the corresponding unit power of the LED group when the light emitting amount I1 is driven;

A second branch loop: the first sub-switching unit Q1 and the third sub-switching unit Q3 are turned off, the second sub-switching unit Q2 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a second sub-loop consisting of the dc power supply U, the first LED group LED1, the third LED group LED3, the second sub-switching unit Q2 and the current limiting device Q0 by a second current I2, the power P2 of the second sub-loop is V × I2, the light emitting amount L2 of the LED group is (V1+ V3) × I2 × K2, and K2 is the unit power corresponding to the light emitting amount of the LED group when the current I2 is driven;

a third branch loop: the second sub-switching unit Q2 and the third sub-switching unit Q3 are turned off, the first sub-switching unit Q1 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a third sub-loop composed of the dc power supply U, the second LED group LED2, the third LED group LED3, the first sub-switching unit Q1 and the current limiting device Q0 by a third current I3, the power P3 of the third sub-loop is V × I3, the light emitting amount L3 of the LED group is (V2+ V3) × I3 × K3, and K3 is the unit power corresponding to the light emitting amount of the LED group when the current I3 is driven;

a fourth loop: the first sub-switching unit Q1 is turned off, the second sub-switching unit Q2 and the third sub-switching unit Q3 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a fourth branch circuit composed of the dc power supply U, the first LED group LED1, the second sub-switching unit Q2, the third sub-switching unit Q3 and the current limiting device Q0 by a fourth current I4, the power P4 of the fourth branch circuit is V × I4, the light emitting amount L4 of the LED group is V1 × I4 × K4, and K4 is the unit power light emitting amount corresponding to the LED group when the current I4 is driven;

A fifth branch loop: the second sub-switching unit Q2 is turned off, the first sub-switching unit Q1 and the third sub-switching unit Q3 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a fifth loop consisting of the direct current power supply U, the second LED group LED2, the first sub-switching unit Q1, the third sub-switching unit Q3 and the current limiting device Q0 by a fifth current I5, the power P5 of the fifth loop is V × I5, the light emission amount L5 of the LED group is V2 × I5 × K5, and K5 is the unit power light emission amount corresponding to the LED group when the current I5 is driven;

a sixth sub-loop: the third sub-switch unit Q3 is turned off, the first sub-switch unit Q1 and the second sub-switch unit Q2 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a sixth sub-loop composed of the dc power supply U, the third LED group LED3, the first sub-switch unit Q1, the second sub-switch unit Q2 and the current limiting device Q0 by a sixth current I6, the power P6 of the sixth sub-loop is V × I6, the light emitting amount L6 of the LED group is V3 × I6 × K6, and K6 is the unit power light emitting amount corresponding to the LED group when the current I6 is driven.

The operation of the present embodiment will be described based on the variation of the output voltage of the dc power supply.

When V1+ V2+ V3> V ≧ V1+ V2, the first to sixth sub-circuits are sequentially sorted into the first to sixth priority-level circuits, and theoretically, the control unit D1 may control any one operation or any plurality of alternate operations in the first to sixth priority-level circuits. Selecting a first priority loop operation from the perspective of efficiency conversion optimization; the first priority loop and the second priority loop are selected to operate alternately from the viewpoint of optimization in terms of efficiency conversion and improvement in lighting effect because the LED groups are all lit.

When V1+ V2> V ≧ V1+ V3, the second to sixth sub-circuits are sequentially sorted into the first to fifth priority sub-circuits, and theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the first to fifth priority sub-circuits. Selecting a first priority loop operation from the perspective of efficiency conversion optimization; the first priority loop and the second priority loop are selected to operate alternately from the viewpoint of optimization in terms of efficiency conversion and improvement in lighting effect because the LED groups are all lit.

When V1+ V3> V ≧ V2+ V3, the third to sixth sub-loops are sequentially sorted into the first to fourth priority loops, theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the first to fourth priority loops. Selecting a first priority loop operation from the perspective of efficiency conversion optimization; the first priority loop and the second priority loop are selected to operate alternately from the viewpoint of optimization in terms of efficiency conversion and improvement in lighting effect because the LED groups are all lit.

When V is more than V and is more than V2+ V3 and more than V is more than V1, the fourth to the sixth branch circuits are sequentially sequenced into the first to the third priority grade circuits, and theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the first to the third priority grade circuits. Selecting a first priority loop operation from the perspective of efficiency conversion optimization; the first priority level loop, the second priority level loop and the third priority level loop are selected to alternately operate from the viewpoint that the LED groups are all lighted to improve the lighting effect.

When V1 is greater than V and is larger than or equal to V2, the fifth sub-loop and the sixth sub-loop are sequentially ordered into a first priority loop and a second priority loop, and theoretically, the control unit D1 can control any one operation or two alternate operations of the first priority loop and the second priority loop. Selecting a first priority loop operation from the perspective of efficiency conversion optimization; both the first priority loop and the second priority loop cannot be realized from the viewpoint of improvement of the illumination effect when all the LED groups are lit.

When V2> V ≧ V3, only one sixth subcircuit can be operated, and only the third LED group LED3 can be lit.

When V < V3, all the sub-loops cannot operate and all the LED groups cannot be lit.

The control unit D1 controls the sub-loop current and the main loop current of the first to sixth sub-loops, PM is enabled to be approximately equal to P1, P2, P3, P4, P5 and P6, the output power change of the direct current power supply can be enabled not to exceed a first preset threshold value when V is larger than or equal to V3, or LM is enabled to be approximately equal to L1, L2, L3, L4, L5 and L6, the light emission quantity change of the LED group can not exceed a second preset threshold value when V is larger than or equal to V3, and therefore the brightness change can be reduced or eliminated. When V is larger than or equal to V2+ V3, the first priority level circuit and the second priority level circuit are selected to alternately operate, so that all the LED groups are lightened; or when V is more than or equal to V1, the first priority level loop, the second priority level loop and the third priority level loop are selected to alternately operate so that all the LED groups are lighted. It should be added that, in order to simplify the complexity of the circuit design, in practical applications, only the difference between the power of part of the sub-loops and the power of the main loop may be set not to exceed the first preset threshold, for example, only the sub-loop with a high priority level is set; similarly, it is also possible to set only the difference between the light emission amounts of the LED groups of the partial sub-circuits and the light emission amount of the LED group of the main circuit not to exceed the second preset threshold, for example, to set only the sub-circuit having a high priority.

When n is 2 and m is 1, the circuit configuration of the control circuit 1 and the driving circuit 2 is schematically illustrated in fig. 8, and in this case, the sub-switching unit Q1 corresponds to the LED2, and its implementation concept is described as follows:

for convenience of explanation of the concept of the embodiment of fig. 8, it is assumed that the light emitting amounts per unit power of the first LED group LED1 and the second LED group LED2 are the same under the same driving current, the on-state voltage drop of the first LED group is V1, and the on-state voltage drop of the second LED group is V2; the output voltage of the dc power supply U is V.

When V is greater than or equal to V1+ V2, the control unit D1 controls the sub-switch unit Q1 to turn off, and the control unit D1 controls the on-resistance of the current-limiting device Q0 to turn on the main circuit composed of the dc power supply U, the first LED group LED1, the second LED group LED2, and the current-limiting device Q0 by the main circuit current IM, at this time, the output power PM of the dc power supply is V × IM, the light emission quantity LM of the LED group is IM × (V1+ V2) × KM, and KM is the unit power light emission quantity corresponding to the LED group when driving the current IM.

When V1+ V2> V ≧ V1, the sub-switch unit Q1 is turned on, the control unit D1 controls the on-resistance of the current-limiting device Q0 to turn on a sub-loop consisting of the dc power supply U, the first LED group LED1, the sub-switch unit Q1, and the current-limiting device Q0 with a sub-loop current I1, a power P1 of the sub-loop is V × I1, a light emission amount L1 of the LED group is V1 × I1 × K1, and K1 is a unit power light emission amount corresponding to the LED group when the LED group drives the current I1.

When V1> V, neither the main loop nor the subcircuit can operate, and all LED groups cannot be lit.

The control unit D1 controls the main loop current and the sub loop current to enable PM to be approximately equal to P1, so that the output power change of the direct current power supply does not exceed a first preset threshold value when V is larger than or equal to V1, or the light emitting quantity change of the LED group does not exceed a second preset threshold value when V is larger than or equal to V1 to reduce or eliminate the brightness change.

It should be added that the assumption in the above embodiment is not a necessary condition, and the expected effect of the present invention can still be achieved when the assumption is changed and the control unit D1 controls the operation state of the different sub-switching units to be changed accordingly without departing from the spirit of the present invention. The same is assumed in the following examples. Compared with fig. 7, only one sub-switch unit is arranged in fig. 8, only one sub-loop can be formed, and alternate conduction of at least two sub-loops cannot be realized. However, the circuit of fig. 8 is simple and low in implementation cost.

When the current-limiting device Q0 is a resistor, a specific circuit structure diagram is shown in fig. 9. The current-limiting device Q0 is a resistor, which is not directly connected to the control unit D1, the current of the resistor Q0 is proportional to the voltage VQ0 at its two ends, the voltage VQ0 is not directly controlled by the control unit D1, but is determined by the output voltage V of the dc power supply U and the sum VZ of the conduction voltage drops of the LED groups that are conducted and included in the main loop or the sub-loop, and the formula is expressed as: VQ0 is V-VZ, VZ is associated with the LED group being turned on and with the control unit controlling the on or off state of the sub-switching unit, so the voltage VQ0 across resistor Q0 and the current across resistor Q0 are also controlled by control unit D1. The sum of the conduction voltage drops of the LED groups of the main loop and the sub loop is properly configured, and the desired main loop current and sub loop current can be obtained. In engineering application, if the precision requirement on the LED current is not high, in order to reduce the cost, a resistor can be used as a current limiting device instead of a field effect transistor or a triode, so that the large-range fluctuation of the LED current is limited.

At least a part of the control circuit 1 in this embodiment is integrated in one or more integrated circuits, and at least a part includes at least one of the sub-switching unit, part or all of the control unit, and the current limiting device. Further, at least a portion of the rectifier in the driver circuit 2 may also be included in one or more of the integrated circuits.

In this embodiment, when the output voltage of the dc power supply is greater than or equal to the sum of the conduction voltage drops of all the LED groups, all the LED groups operate with the main loop current; under the condition that the output voltage of the direct current power supply is smaller than the sum of the conduction voltage drops of all the LED groups, the sub-loop is selected to operate by sub-loop current by controlling the on-off of the sub-switch unit, and the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed a preset threshold value by setting the sub-loop current to be larger than the main loop current. And when the operating conditions of the plurality of sub-loops are met, the plurality of sub-loops are respectively sequenced into a first-level sub-loop, a second-level sub-loop and a higher-level priority sub-loop from high to low according to the closeness degree of the sum of the voltage drops of the conducted LED groups and the output voltage of the direct-current power supply, the control circuit is controlled by a rotation frequency to rotate and operate in at least two different sub-loops, and the at least two different sub-loops are selected from the plurality of sub-loops. The selected LED groups conducted in the sub-loop comprise all the LED groups, so that all the LED groups can be lightened. The sub-loop current is controlled to be larger than the main loop current, the sub-loop current of the low-level priority sub-loop is controlled to be larger than the sub-loop current of the high-level priority sub-loop, the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed a preset threshold value when the main loop or any sub-loop runs is achieved, and the light emitting effect is improved. Furthermore, the change of the LED light emitting quantity does not exceed the preset threshold value, so that the light emitting stroboflash of the LED is reduced, and the harm to human eyes is reduced.

The preset threshold values are a first preset threshold value and a second preset threshold value, and may be a percentage of a nominal parameter of the implemented commodity, such as power, luminous flux, etc., which is identified on the nameplate of the commodity, for example, the percentage is ± 3%.

EXAMPLE III

The present embodiment is substantially the same as the second embodiment, except that the current limiting device Q0 and at least one LED group adjacent to the current limiting device Q0 form at least one serial branch, x of the m sub-switch units Q1 … Qm are respectively connected in parallel at two ends of the serial branch, and the remaining m-x sub-switch units are respectively connected in parallel at two ends of the corresponding LED group, as shown in fig. 10, x is an integer, and x is greater than or equal to 1 and less than or equal to m.

At this time, when the output voltage of the dc power supply U is greater than or equal to the sum of the on-state voltage drops of all the LED groups, all the sub-switching units are turned off, and the control unit D1 sets the main loop current by controlling the on-state impedance of the current limiting device Q0. When the output voltage of the direct current power supply U is smaller than the sum of the conduction voltage drops of all the LED groups, and when at least one of the x sub-switch units connected in parallel to two ends of the serial branch consisting of the corresponding LED group and the current limiting device Q0 is conducted, the conducted sub-switch units connected in parallel to two ends of the serial branch consisting of the corresponding LED group and the current limiting device Q0 bypass the current limiting device Q0, and at the moment, the sub-loop does not include the current limiting device Q0, so the control unit D1 sets the sub-loop current by controlling the conduction impedance of the conducted sub-switch units; when the x sub-switch units connected in parallel at the two ends of the serial branch consisting of the corresponding LED group and the current limiting device Q0 are all cut off, the switched-on sub-switch units are connected in parallel at the two ends of the corresponding LED group, the current limiting device Q0 is not bypassed any more, the sub-loop comprises a current limiting device Q0, and the control unit D1 sets the current of the sub-loop by controlling the on-resistance of the current limiting device Q0.

Such a connection allows both the shunt switch unit and the current limiting device Q0 connected in parallel across the series branch to be more easily integrated on an integrated circuit, reducing circuit size, such as an integrated circuit implemented using the dual base island framework described in some embodiments of the present invention.

Preferably, when the last-stage branch switch unit Qm is connected in parallel to the two ends of the serial branch circuit formed by the corresponding LED group LEDn and the current-limiting device Q0, the composition of the first-stage priority branch circuit and the second-stage priority branch circuit and the number of the branch circuits are not affected.

The control circuit and the driving circuit in fig. 8 are modified as above to form a circuit in which when n is 2 and m is 1 as shown in fig. 11, the sub-switching unit Q1 is connected in parallel to both ends of the serial branch consisting of the corresponding LED group LED2 and the current limiting device Q0. In fig. 11, assuming that the light emission amounts per unit power of the first LED group LED1 and the second LED group LED2 are the same under the same driving current, the on-state voltage drop of the first LED group is V1, and the on-state voltage drop of the second LED group is V2; the output voltage of the dc power supply U is V.

When V1+ V2> V ≧ V1, the sub-switch unit Q1 is turned on, a branch between the second LED group LED2 and the current limiting device Q0 is bypassed, the control unit D1 controls the on-resistance of the sub-switch unit Q1 to turn on the sub-circuit composed of the dc power supply U, the first LED group LED1, and the sub-switch unit Q1 with a sub-circuit current I1, the power P1 of the sub-circuit is V × I1, the light emission amount L1 of the LED group is V1 × I1 × K1, and K1 is the unit power light emission amount corresponding to the LED group when driving the current I1.

The control unit D1 controls the main loop current and the sub loop current to make PM ≈ P1, so that the output power variation of the direct current power supply does not exceed a first preset threshold value when V is larger than or equal to V1, or the LM ≈ L1 is made, so that the light emission variation of the LED group does not exceed a second preset threshold value when V is larger than or equal to V1, and the brightness variation is reduced or eliminated. In addition, the current limiting device Q0, the sub-switch unit Q1 and the control unit D1 are partially or completely integrated in the same integrated circuit, so that the cost advantage is obvious.

Example four

The present embodiment provides a control method, as shown in fig. 12, the control method includes the following steps:

S1, judging the magnitude relation between the output voltage and the sum of the conduction voltage drops of the n LED groups, and respectively entering the step S21 and the step S22 according to the magnitude relation between the output voltage and the sum of the conduction voltage drops of the n LED groups.

The control circuit judges the magnitude relation between the output voltage of the direct current power supply and the sum of the conduction voltage drops of the n LED groups by detecting a voltage or current signal on the main loop. The method includes but is not limited to the following three judgment modes:

firstly, directly detecting the output voltage of a direct current power supply, comparing the output voltage with the sum of the conduction voltage drops of n LED groups, and determining the magnitude relation of the output voltage and the sum of the conduction voltage drops of the n LED groups;

secondly, by detecting voltage signals at two ends of the current limiting device, when the voltage signals are larger than a preset voltage threshold, the output voltage of the direct current power supply is considered to be larger than the sum of the conduction voltage drops of the n LED groups, otherwise, the output voltage is considered to be smaller than the sum of the conduction voltage drops of the n LED groups;

thirdly, by detecting a current signal flowing through a main loop (such as a current limiting device), when the current signal is greater than a preset current threshold, the output voltage of the direct current power supply is considered to be greater than the sum of the conduction voltage drops of the n LED groups, otherwise, the output voltage is considered to be less than the sum of the conduction voltage drops of the n LED groups.

Two conditions are judged according to the judgment method:

In the first case: when the output voltage of the direct current power supply is greater than or equal to the sum of the conduction voltage drops of the n LED groups, the step S21 is carried out;

in the second case: when the output voltage of the direct current power supply is smaller than the sum of the conduction voltage drops of the n LED groups, the step S22 is carried out;

and S21, turning off the m sub-switch units to form a main loop comprising the n LED groups and the direct current power supply.

When the output voltage of the direct current power supply is greater than or equal to the sum of the conduction voltage drops of the n LED groups, the direct current power supply can provide enough power supply for the n LED groups, so that the control unit turns off the m sub-switch units in the driving circuit to enable the n LED groups to be conducted. At the moment, the direct current power supply and the n LED groups are connected in series to form a main loop.

And S22, at least one sub-switch unit is turned on, and the rest sub-switch units are turned off to form a sub-loop comprising the turned-on sub-switch unit, the turned-on LED group and the direct current power supply.

When the output voltage of the direct current power supply is less than the sum of the conduction voltage drops of the n LED groups, the direct current power supply cannot provide enough power supply for the n LED groups, so the control unit turns on at least one sub-switch unit according to the output voltage, and turns off the rest sub-switch units to turn on part of the LED groups. At the moment, the sub-loop comprises a switched-on sub-switch unit, a switched-on LED group and a direct-current power supply, the switched-on LED group comprises an LED group corresponding to the switched-off sub-switch unit and an LED group which is not corresponding to the sub-switch unit and is switched on all the time, and the sum of the switching-on voltage drops of the switched-on LED group is smaller than the output voltage of the direct-current power supply U.

In this embodiment, when the output voltage of the dc power supply is greater than or equal to the sum of the conduction voltage drops of all the LED groups, all the LED groups are turned on; under the condition that the output voltage of the direct-current power supply is smaller than the sum of the conduction voltage drops of all the LED groups, the sub-loop is selected to conduct part of the LED groups in the circuit by controlling the conduction or the cut-off of the sub-switch unit, and the condition that the LED lamp cannot be lightened when the output voltage of the direct-current power supply is smaller than the sum of the conduction voltage drops of all the LED groups cannot occur.

EXAMPLE five

The present embodiment is further optimized based on the fourth embodiment, as shown in fig. 13. In step S21, the control unit further controls the main loop current when the main loop is formed; in step S22, when the sub-loop is formed, the control unit controls the sub-loop current, and the control unit also controls the sub-loop current to be larger than the main loop current.

In this embodiment, on the basis of the fourth embodiment, the control unit controls the sub-loop current and the main loop current to make the sub-loop current larger than the main loop current, so that the change of the output power of the dc power supply and/or the change of the LED light emission amount do not exceed the preset threshold, thereby reducing or even eliminating the change of the LED light emission amount.

EXAMPLE six

This embodiment is further optimized based on the fifth embodiment, and the driving circuit is divided into two cases, which are controlled separately, as shown in fig. 14 and 15. Fig. 14 shows a first circuit configuration: when the m sub-switch units are respectively connected in parallel at two ends of the corresponding m LED groups, the control method of the driving circuit is adopted; fig. 15 shows a second circuit configuration: the current limiting device and at least one LED group adjacent to the current limiting device form at least one serial branch, x of the m sub-switch units are respectively connected in parallel at two ends of the serial branch, and the rest m-x sub-switch units are respectively connected in parallel at two ends of the corresponding LED group.

As shown in fig. 14, when the m sub-switch units are respectively connected in parallel to two ends of the corresponding m LED groups, the control method includes the following steps:

wherein step S1 is the same as in the fourth embodiment, and is not described herein again.

In step S21, controlling the main loop current includes setting the main loop current through an impedance of the current limiting device.

In step S22, turning on at least one of the sub-switching cells and turning off the remaining sub-switching cells includes controlling the driving circuit to alternately operate at least two different sub-circuits selected from the plurality of sub-circuits at an alternate frequency; controlling the sub-loop current includes controlling an on-resistance of the current limiting device to set the sub-loop current.

The sub-switch units can form a plurality of sub-loops according to different on or off states, the sub-loops are respectively sequenced into a first-level sub-loop, a second-level sub-loop and a higher-level sub-loop from high to low according to the proximity degree of the voltage drop sum of the turned-on LED groups and the output voltage, the driving circuit is controlled to alternately operate at least two different sub-loops selected from the sub-loops by a rotation frequency, namely the sub-switch units are alternately turned on or off by the rotation frequency and alternately operate on the at least two different sub-loops.

The selected LED groups which are conducted in the at least two different sub-loops comprise all n LED groups, so that all the LED groups can be conducted in one rotation period; and the at least two different selected sub-loops at least comprise a first-level priority sub-loop and a second-level priority sub-loop, so that the operation efficiency of the driving circuit is ensured.

When the m sub-switch units are respectively connected in parallel at two ends of the corresponding m LED groups, all sub-loops comprise current limiting devices, so that the control of the current of the sub-loops is realized by controlling the on-resistance of the current limiting devices.

As shown in fig. 15, the current limiting device and at least one LED group adjacent to the current limiting device form at least one serial branch, and when x of the m sub-switch units are respectively connected in parallel to two ends of the serial branch and the remaining m-x sub-switch units are respectively connected in parallel to two ends of the corresponding LED group, the control method includes the following steps:

In step S22, turning on at least one of the sub-switching cells and turning off the remaining sub-switching cells includes controlling the driving circuit to alternately operate at least two different sub-circuits selected from the plurality of sub-circuits at an alternate frequency; when at least one of the x sub-switch units connected in parallel with the two ends of the serial branch consisting of the corresponding LED group and the current limiting device is switched on, setting sub-loop current by controlling the on-resistance of the switched-on sub-switch unit; when the x branch switch units connected in parallel at the two ends of the serial branch circuit consisting of the corresponding LED group and the current limiting device are all cut off, the branch loop current is set through the impedance of the current limiting device.

The sub-switch units can form a plurality of sub-loops according to different on or off states, the sub-loops are respectively sequenced into a first-level sub-loop, a second-level sub-loop and a higher-level sub-loop from high to low according to the proximity degree of the voltage drop sum of the turned-on LED groups and the output voltage, and the driving circuit is controlled to operate at least two different sub-loops selected from the sub-loops in a rotating mode through a rotating frequency. The selected LED groups corresponding to the cut-off branch switches in at least two different branch loops comprise all n LED groups, so that all the LED groups can be switched on in one rotation period; and the at least two different selected sub-loops at least comprise a first-level priority sub-loop and a second-level priority sub-loop, so that the operation efficiency of the driving circuit is ensured.

When the branch switch units connected in parallel at two ends of the serial branch circuit formed by the corresponding LED group and the current limiting device are all cut off, the switched-on branch switch units are connected in parallel at two ends of the corresponding LED group, and the current limiting device is not bypassed, namely, the branch circuit comprises the current limiting device, so that the current of the branch circuit is set through the impedance of the current limiting device.

When at least one of the branch switch units connected in parallel with the two ends of the serial branch circuit consisting of the corresponding LED group and the current limiting device is conducted, the current limiting device is bypassed, and the branch circuit does not comprise the current limiting device, so that the current of the branch circuit is set by controlling the conducting impedance of the conducted branch switch unit.

In the process of controlling the main loop current and the sub-loop current, when the current limiting device comprises a field effect transistor and/or a triode, the impedance of the current limiting device is realized by controlling the conduction degree of the field effect transistor and/or the triode; by setting the sub-loop current to be larger than the main loop current, the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed the expected range. When a plurality of sub-loop operation conditions are met, the sub-loop current is controlled to be larger than the main loop current, the sub-loop current of the low-level priority sub-loop is controlled to be larger than the sub-loop current of the high-level priority sub-loop, and therefore the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed a preset threshold value when the main loop or any sub-loop operates. When the direct current power supply is a pulsating direct current power supply, stroboflash can be reduced or even eliminated.

It should be noted that, three implementation methods and corresponding illustrations are given in the fourth embodiment and corresponding fig. 12 and fig. five and corresponding fig. 13 and fig. six and corresponding fig. 14 and fig. 15, wherein the first step, the second step, the sequence of the paragraphs and the sequence of the flowcharts are only one way to describe the implementation method of the present invention, and do not limit the sequence of the implementation method of the present invention, and various changes or modifications may be made to the implementation methods without departing from the principle and spirit of the present invention, but all of the changes and modifications fall within the protection scope of the present invention.

On the basis of the fifth embodiment, when the operating conditions of the plurality of sub-loops are met, the plurality of sub-loops are sorted into the first-level sub-loop, the second-level sub-loop and the higher-level priority sub-loop according to the proximity degree between the sum of the voltage drops of the turned-on LED groups and the output voltage of the direct-current power supply, and the driving circuit is controlled to operate at least two different sub-loops selected from the plurality of sub-loops in a rotating mode at a rotating frequency. The selected LED groups conducted in the sub-loop comprise all the LED groups, so that all the LED groups can be lightened. And meanwhile, the sub-loop current is controlled to be larger than the main loop current, and the sub-loop current of the low-level priority sub-loop is controlled to be larger than the sub-loop current of the high-level priority sub-loop, so that the change of the output power of the direct current power supply and/or the change of the LED light emitting quantity do not exceed a preset threshold when the main loop or any sub-loop runs. Furthermore, the change of the LED light emitting quantity does not exceed the preset threshold value, so that the light emitting stroboflash of the LED is reduced, and the harm to human eyes is reduced.

EXAMPLE seven

The present embodiment provides a lighting device, which is manufactured by using the driving circuit described in the first to third embodiments.

Example eight

As shown in fig. 5, the present embodiment provides a control circuit 1 and a driving circuit 2, the control circuit 1 is used for controlling the operation of n LED arrays, and includes: a control unit D1; and m switch units configured to respectively and correspondingly couple m LED arrays of the n LED arrays when the control circuit 1 drives the n LED arrays, wherein the control terminals of the m switch units are respectively connected to the control unit D1 and controlled by the control unit D1 to bypass the corresponding LED arrays, wherein m and n are integers, n is greater than or equal to 2, m is greater than or equal to 1, and m is less than or equal to n.

Wherein, n LED arrays are respectively LEDs 1 … LEDn, m switch units are respectively Q1 … Qm, and each switch unit respectively corresponds to an LED array, specifically, as an example, fig. 5 shows a specific corresponding relationship between a switch unit and an LED array: the switch unit Q1 corresponds to the LED1, the switch unit Q2 corresponds to the LED2, and the switch unit Qm corresponds to the LEDn, but this does not limit the present embodiment, and those skilled in the art can understand that all technical solutions in which the switch units correspond to the LED arrays one to one are within the protection scope of the present embodiment.

Specifically, in this embodiment, the bypass and the bypass cancellation of the LED array are realized by connecting the switch unit in parallel with the corresponding LED array.

The m switching units bypass the corresponding one or more LED arrays by being controlled by the selective conduction of the control unit D1, for example, when Q1 is turned on, the LED1 is bypassed; when Q1, Q2, and Qm are all on, LED1, LED2, and LEDn are all bypassed.

The m switch units are controlled by the control unit D1 to be selectively turned on, that is, the m switch units are turned on and off by the control unit D1, and specifically, the m switch units respectively have control terminals connected to the control unit D1 and are controlled by the control unit D1 to be switched to at least an on, regulation or off state.

The m switching units may include one or any combination of field effect transistors, triodes, transistors, power transistors, or MOS transistors, and may be N-type/NPN-type devices or P-type/PNP-type devices.

In this embodiment, m switching units are taken as field effect transistors for illustration, and more specifically, the field effect transistors may be N-type devices or P-type devices, and for convenience of illustration, the field effect transistors are taken as N-type devices for illustration.

The driving voltage of the n LED arrays is provided by a direct current power supply U, and the direct current power supply U can be a steady direct current power supply or a pulsating direct current power supply. A steady dc power supply refers to a non-periodic fluctuating dc power supply, such as a battery output or a dc power supply generated by a high frequency switching power supply; the pulsating direct current power supply refers to a periodically fluctuating direct current power supply, such as a power supply powered by alternating current rectification, or a power supply converted by other conversion methods, wherein the rectification methods include full-bridge rectification, full-wave rectification, half-wave rectification or voltage-multiplying rectification. For example, the pulsating dc power supply shown in fig. 2 includes a commercial power supply, a rectifier and at least one capacitor, wherein an input terminal of the rectifier is connected to the commercial power supply, the capacitor is connected in parallel to two terminals of a dc output terminal of the rectifier, and the dc output terminal of the rectifier outputs a pulsating dc voltage having a pulsating cycle to supply power.

In fig. 5, two connection lines are provided between the control unit D1 and each sub-switch unit Q1 … Qm, which is only an illustration, and in practical applications, one or more connection lines may be provided according to the specific implementation of the sub-switch unit or the control unit D1.

It should be noted that m may be smaller than n, and at this time, part of the LED array cannot be bypassed by m switch units; m and n may be equal, and at this time, n LED arrays may be bypassed by m switching units.

It should be noted that the foregoing series connection includes direct connection through a wire or indirect connection through any device, such as indirect connection through a resistor, and the connection sequence is not limited, and the meaning of the series connection mentioned hereinafter is the same.

In the control circuit 1 provided in this embodiment, when the output voltage of the dc power supply U is greater than or equal to the sum of the on-voltage drops of the n LED array LEDs 1 … LEDn, the control unit D1 turns off the m switch units Q1 … Qm, so as to form a main loop including the n LED array LEDs 1 … LEDn and the dc power supply U, where the n LED array LEDs 1 … LEDn are all turned on in the main loop.

When the output voltage of the dc power supply U is less than the sum of the turn-on voltage drops of the n LED arrays LEDs 1 … LEDn, the control unit D1 turns on at least one switch unit and turns off the remaining switch units to form a bypass loop including the dc power supply U, the turned-on switch units, and the LED arrays that are not bypassed, wherein the sum of the turn-on voltage drops of the LED arrays that are not bypassed is less than the output voltage of the dc power supply U.

When m is less than n, the LED array which is turned on also comprises the LED array which is not connected with the switch unit in parallel and can not be bypassed.

In the present specification, for convenience of description, the sub-loop, the bypass loop and the main loop may be also collectively referred to as a loop, and correspondingly, a current flowing through the sub-loop may be referred to as a sub-loop current, a current flowing through the bypass loop may be referred to as a bypass loop current, a current flowing through the main loop may be referred to as a main loop current, and a current flowing through the loop may be collectively referred to as a loop current.

In this embodiment, when the output voltage of the dc power supply U is greater than or equal to the sum of the conduction voltage drops of the n LED arrays, the n LED arrays are all turned on; when the output voltage of the direct-current power supply U is smaller than the sum of the conduction voltage drops of the n LED arrays, the bypass loop is selected to conduct part of the LED arrays in the circuit by controlling the conduction or the cut-off of the switch unit, and the condition that the lighting device cannot be normally lightened when the output voltage is smaller than the sum of the conduction voltage drops of the n LED arrays cannot occur.

Example nine

This embodiment is further optimized on the basis of some of the above embodiments, as shown in fig. 6, a control circuit 1 and a driving circuit 2 are provided, and further include a current limiting device Q0 connected in the control circuit 1, so as to form a series loop with the n LED array LEDs 1 … LEDn and the dc power source U when the control circuit 1 drives the n LED array LEDs 1 … LEDn. The current limiting device Q0 is an N-type fet, and the control terminal of the N-type fet is connected to the control unit D1, and the on-resistance of the N-type fet can be set by the control of the control unit D1, thereby setting the current flowing through the current limiting device Q0. Specifically, the current limiting device Q0 and m switching units each have a control terminal connected to the control unit D1, and the current limiting device and/or at least part of the m switching units are operable to adjust respective on-resistances according to control signals of the respective control terminals, thereby setting the current of the corresponding main loop/bypass loop.

When the output voltage of the dc power supply U is greater than or equal to the sum of the on-voltage drops of the n LED array LEDs 1 … LEDn, the control unit D1 turns off the m switching units Q1 … Qm to form a main circuit including the current limiting device Q0, the n LED array LEDs 1 … LEDn, and the dc power supply U, where the n LED array LEDs 1 … LEDn are all turned on to obtain the highest energy conversion efficiency, and the control unit D1 controls the on-resistance of the current limiting device Q0 to set the main circuit current.

When the output voltage of the dc power supply U is less than the sum of the turn-on voltage drops of the n LED arrays LED1 … LEDn, the control unit D1 turns on at least one switch unit and turns off the remaining switch units, at this time, although some LED arrays in the circuit are turned on, the situation that the LED arrays cannot be lit is avoided, but the overall luminance is reduced accordingly due to the reduction of the number of LED arrays that are turned on. In order to solve the technical problem at least to some extent, in this embodiment, the current limiting device Q0 is set, and the on-resistance of the current limiting device Q0 is controlled by the control unit D1 to set the current flowing through the current limiting device Q0, so that the power of the LED array turned on in the main loop and the bypass loop is kept substantially unchanged, or the luminous quantity of the LED array turned on in the main loop is kept substantially unchanged, and of course, in specific implementation, the power of the LED array turned on in the bypass loop may be controlled to be smaller than the power of the LED array turned on in the main loop, so that the power of the LED array when the output voltage of the dc power source U is lower, or the output power of the dc power source U when the output voltage of the dc power source U is lower, which is more consistent with the characteristics of the conventional lighting, such as an incandescent lamp.

The following description will be given taking an example in which the power of the LED array turned on in the main circuit and the bypass circuit is maintained substantially unchanged, and specifically, as shown in fig. 7, the description will be given taking a case where n is 3 and m is 3 in the driving circuit 2 as an example.

The three LED arrays are respectively a first LED array LED1, a second LED array LED2 and a third LED array LED3, and the conduction voltage drops of the three LED arrays are respectively V1, V2 and V3, wherein V1 is more than or equal to V2 and more than or equal to V3, and V2+ V3 is more than or equal to V1; the output voltage of the direct current power supply U is V; the first switching unit Q1, the second switching unit Q2, and the third switching unit Q3 are respectively connected in parallel to the first to third LED arrays.

When V is greater than or equal to V1+ V2+ V3, the control unit D1 controls all three switch units to be turned off, the control unit D1 controls the on-resistance of the current limiting device Q0, so that the current of a main loop formed by the dc power supply U, the first LED array LED1, the second LED array LED2, the third LED array LED3 and the current limiting device Q0 is IM, at this time, the output power PM of the dc power supply U is vxm, and the light emission quantity LM of the LED array is imx (V1+ V2+ V3) xm, where KM is the unit power light emission quantity corresponding to the LED array when the driving current is IM.

When V < V1+ V2+ V3, six different bypass circuits, i.e., first to sixth bypass circuits, are formed according to the on/off states of different switch units, as shown in table 2:

TABLE 2

A first bypass circuit: the first switching unit Q1 and the second switching unit Q2 are turned off, the third switching unit Q3 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a first bypass loop composed of the dc power supply U, the first LED array LED1, the second LED array LED2, the third switching unit Q3 and the current limiting device Q0 by a first current I1, the power P1 of the first bypass loop is V × I1, the light emission amount L1 of the LED array is (V1+ V2) × I1 × K1, and K1 is the unit power corresponding to the light emission amount of the LED array when the driving current is I1;

a second bypass circuit: the first switching unit Q1 and the third switching unit Q3 are turned off, the second switching unit Q2 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a second bypass loop composed of the dc power supply U, the first LED array LED1, the third LED array LED3, the second switching unit Q2, and the current limiting device Q0 at a second current I2, the power P2 of the second bypass loop is V × I2, the light emission amount L2 of the LED array is (V1+ V3) × I2 × K2, and K2 is the corresponding unit power of the LED array when the driving current is I light emission amount 2;

a third bypass circuit: the second switching unit Q2 and the third switching unit Q3 are turned off, the first switching unit Q1 is turned on, the control unit D1 controls the on resistance of the current limiting device Q0 to turn on a third bypass circuit composed of the dc power supply U, the second LED array LED2, the third LED array LED3, the first switching unit Q1 and the current limiting device Q0 by a third current I3, the power P3 of the third bypass circuit is V × I3, the light emitting amount L3 of the LED array is (V2+ V3) × I3 × K3, and K3 is the corresponding unit power of the LED array when the driving current is I light emitting amount 3;

A fourth bypass circuit: the first switch unit Q1 is turned off, the second switch unit Q2 and the third switch unit Q3 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a fourth bypass circuit composed of the dc power supply U, the first LED array LED1, the second switch unit Q2, the third switch unit Q3 and the current limiting device Q0 by a fourth current I4, the power P4 of the fourth bypass circuit is V × I4, the light emitting amount L4 of the LED array is V1 × I4 × K4, and K4 is the unit power light emitting amount corresponding to the LED array when the driving current is I4;

a fifth bypass circuit: the second switching unit Q2 is turned off, the first switching unit Q1 and the third switching unit Q3 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a fifth bypass loop consisting of the dc power supply U, the second LED array LED2, the first switching unit Q1, the third switching unit Q3 and the current limiting device Q0 at a fifth current I5, the power P5 of the fifth bypass loop is V × I5, the light emission amount L5 of the LED array is V2 × I5 × K5, and K5 is the unit power light emission amount corresponding to the LED array when the current I5 is driven;

a sixth bypass circuit: the third switching unit Q3 is turned off, the first switching unit Q1 and the second switching unit Q2 are turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a sixth bypass circuit composed of the dc power supply U, the third LED array LED3, the first switching unit Q1, the second switching unit Q2 and the current limiting device Q0 by a sixth current I6, the power P6 of the sixth bypass circuit is V × I6, the light emission amount L6 of the LED array is V3 × I6 × K6, and K6 is the unit power light emission amount corresponding to the LED array when the current I6 is driven.

For convenience of description, in the present embodiment, it is assumed that the unit power light emission amount of each LED array is the same under the same driving current; the control unit D1 controls the bypass loop current and the main loop current of the first to sixth bypass loops, PM is enabled to be approximately equal to P1P 2P 3P 4P 5P 6, the output power change of the direct current power supply U can be enabled not to exceed a first preset threshold value when V is larger than or equal to V3, or LM is enabled to be approximately equal to L1L 2L 3L 4L 5L 6, the luminous quantity change of the LED array does not exceed a second preset threshold value when V is larger than or equal to V3, the luminous quantity change of the LED array generated when the LED array is switched between the main loop and the bypass loops or between the bypass loops is reduced, and the illumination effect is improved.

The first preset threshold and the second preset threshold can be set according to the actual requirements of the user. For example, the first preset threshold may be set to any one of 2%, 5%, or 10% of the output power of the dc power supply U at the rated voltage; the second set threshold may be set to: when the output voltage of the dc power supply U is the rated voltage, the LED array emits light of 2%, 5%, or 10%. The first preset threshold and the second preset threshold are also applicable to other embodiments, and are not described again.

It should be noted that, in this embodiment, the control process of the current of the main loop/bypass loop is described by controlling the on-resistance of the current limiting device Q0 as an example, in a practical application scenario, the m switching units also have control terminals and are operable to adjust the current of the corresponding bypass loop according to a control signal of the control terminals, that is, the current flowing through at least part of the n LED arrays may also be adjusted jointly by the switching units and the current limiting device Q0.

Although the control circuit provided in this embodiment can keep the amount of light or the output power of the LED array turned on in different bypass loops within a predetermined range, the priorities of the first to sixth bypass loops are changed when the output voltage of the dc power supply U is changed based on the efficiency conversion and/or the lighting effect.

Specifically, when V1+ V2+ V3> V ≧ V1+ V2, theoretically, the control unit D1 may control any one operation or any plurality of alternate operations in the first to sixth bypass loops to ensure conduction of part of the LED arrays. From the viewpoint of efficiency conversion optimization, the priorities of the first to sixth bypass loops are sequentially reduced, that is, the first bypass loop is preferentially selected to operate; from the viewpoint of efficiency conversion and improved lighting effect, the first bypass circuit and the second bypass circuit are preferably selected to be operated alternately, so that all the LED arrays are lit at least once in one alternation period.

When V1+ V2> V ≧ V1+ V3, theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the second to sixth bypass loops to ensure the conduction of part of the LED arrays. From the viewpoint of efficiency conversion optimization, the priorities of the second to sixth bypass loops are sequentially reduced, that is, the second bypass loop is preferentially selected to operate; from the viewpoint of efficiency conversion and improved lighting effect, the second bypass circuit and the third bypass circuit are preferably selected to be operated alternately, so that all the LED arrays are lit at least once in one alternation period.

When V1+ V3> V ≧ V2+ V3, theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the third to sixth bypass loops to ensure the conduction of part of the LED arrays. From the viewpoint of efficiency conversion optimization, the priorities of the third to sixth bypass loops are sequentially reduced, that is, the third bypass loop is preferentially selected to operate; from the viewpoint of both efficiency conversion and improved lighting effect, the third bypass circuit and the fourth bypass circuit are preferably selected to be operated alternately, so that all the LED arrays are lit at least once in one alternate period.

When V2+ V3> V ≧ V1, theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the fourth to sixth bypass loops to ensure conduction of the partial LED arrays. From the viewpoint of efficiency conversion optimization, the priorities of the fourth to sixth bypass loops are sequentially reduced, that is, the fourth bypass loop is preferentially selected to operate; from the viewpoint of both efficiency conversion and improvement of lighting effect, the fourth, fifth and sixth bypass circuits are preferably selected to be operated alternately so that all the LED arrays are lit at least once in one alternation period.

When V1> V ≧ V2, theoretically, the control unit D1 can control any one operation or any plurality of alternate operations in the fifth and sixth bypass loops to ensure the conduction of part of the LED arrays. From the viewpoint of efficiency conversion optimization, the priorities of the fifth to sixth bypass loops are sequentially reduced, that is, the fifth bypass loop is preferentially selected to operate; from the viewpoint of both efficiency conversion and improved lighting effect, it is preferable to select the fifth bypass circuit and the sixth bypass circuit to be operated alternately so that the number of LED arrays to be lit in one alternation period is as large as possible.

When V2> V ≧ V3, only the sixth bypass loop can effect conduction of the LED array, specifically, only the third LED array LED3 can be lit.

When V < V3, all bypass loops cannot operate and all LED arrays cannot be lit.

It should be noted that, in order to simplify the complexity of the circuit design, in practical applications, only the difference between the power of a part of the bypass loop and the power of the main loop may be set not to exceed the first preset threshold, for example, only the bypass loop with a higher priority level is set; similarly, it may be configured that the difference between the light emission amounts of the LED arrays of only a part of the bypass circuits and the light emission amount of the LED array of the main circuit does not exceed the second preset threshold, for example, only the bypass circuit with a higher priority level is configured.

In addition, for convenience of explanation, it is assumed that, as shown in fig. 8, the light emission amounts per unit power of the first LED array LED1 and the second LED array LED2 are the same, the on-state voltage drop of the first LED array is V1, and the on-state voltage drop of the second LED array is V2 under the same driving current; the output voltage of the dc power supply U is V.

When V is greater than or equal to V1+ V2, the control unit D1 controls the switching unit Q1 to be turned off, and the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on the main circuit formed by the dc power supply U, the first LED array LED1, the second LED array LED2 and the current limiting device Q0 by the main circuit current IM, at this time, the output power PM of the dc power supply is V × IM, the light emission quantity LM of the LED array is IM × (V1+ V2) × KM, and KM is the unit power light emission quantity corresponding to the LED array when the current IM is driven.

When V1+ V2> V ≧ V1, the switching unit Q1 is turned on, the control unit D1 controls the on-resistance of the current limiting device Q0 to turn on a bypass loop consisting of the dc power supply U, the first LED array LED1, the switching unit Q1, and the current limiting device Q0 with a bypass loop current I1, a power P1 of the bypass loop is equal to V × I1, a light emission amount L1 of the LED array is equal to V1 × I1 × K1, and K1 is a unit power light emission amount corresponding to the LED array when driving the current I1.

When V1> V, neither the main loop nor the bypass loop can operate and all LED arrays cannot be lit.

The control unit D1 controls the main loop current and the bypass loop current to enable PM to be approximately equal to P1, so that the output power change of the direct-current power supply does not exceed a first preset threshold value when V is larger than or equal to V1, or the light emitting quantity change of the LED array does not exceed a second preset threshold value when V is larger than or equal to V1, and therefore the brightness change is reduced or eliminated.

It should be added that the assumption in the above embodiment is not a necessary condition, and the expected effect of the present invention can still be achieved when the assumption is changed and the control unit D1 controls the operation state of the different switch units to be changed accordingly without departing from the spirit of the present invention. The same is assumed in the following examples.

Compared with fig. 7, only one switch unit is arranged in fig. 8, so that only one bypass circuit can be formed, and the alternate conduction of at least two bypass circuits cannot be realized, but the circuit in fig. 8 is simple, low in realization cost and high in practical application value.

When the current-limiting device Q0 is a resistor, a specific circuit structure diagram is shown in fig. 9. The current-limiting device Q0 is a resistor, which is not directly connected to the control unit D1, the current of the resistor Q0 is proportional to the voltage VQ0 at its two ends, the voltage VQ0 is not directly controlled by the control unit D1, but is determined by the output voltage V of the dc power supply U and the sum VZ of the conduction voltage drops of the LED arrays that are conducted and included in the main loop or the bypass loop, and the formula is expressed as: VQ0 is V-VZ, VZ being related to the LED array being on and the control unit controlling the on or off state of the switching unit, so the voltage VQ0 across resistor Q0 and the current across resistor Q0 are also controlled by control unit D1. By properly configuring the sum of the conduction voltage drops of the LED arrays of the main loop and the bypass loop, the desired main loop current and bypass loop current can be obtained. In engineering application, if the precision requirement on the LED current is not high, in order to reduce the cost, a resistor can be used as a current limiting device instead of a field effect transistor or a triode, so that the large-range fluctuation of the LED current is limited.

Preferably, when at least one of the n LED arrays is bypassed, the current flowing through the n LED arrays or the current of the bypass loop is adjusted to be larger than the current of the main loop when all of the n LED arrays are turned on by the control unit D1, that is, the power of the LED array in the bypass loop is kept substantially constant, or the power variation does not exceed the first preset threshold, by adjusting the current in the bypass circuit.

It should be noted that, in this embodiment, the current limiting device Q0 is an N-type field effect transistor as an example, but this does not limit this embodiment, and in some embodiments, the current limiting device Q0 may be a combined device formed by one or more of a P-type field effect transistor, a triode, and a resistor, and when the current limiting device Q0 is formed by a resistor alone, the resistor is a variable resistor or a non-variable resistor.

It should be noted that, although in this embodiment, the position of the current limiting device Q0 is disposed downstream of the n LED array LEDs 1 … LEDn in the current direction, this does not limit this embodiment, and in some embodiments, the current limiting device Q0 may be disposed upstream of the n LED array LEDs 1 … LEDn in the current direction, or between the n LED array LEDs 1 … LEDn.

Example ten

This embodiment is further optimized on the basis of some of the above embodiments, and provides a control circuit, wherein when m switching units are N-type devices, the LED arrays and the current limiting device Q0 corresponding to/coupled with the m switching units are sequentially arranged along the current direction, wherein both ends of x switching units are connected to the upstream of the current limiting device Q0, and both ends of the remaining m-x switching units are respectively connected to the upstream and downstream of the current limiting device Q0 (or both ends of the remaining m-x switching units are respectively connected to the upstream and downstream of a serial body formed by connecting the current limiting device Q0 and at least one LED array in series), wherein x is an integer, and m ≧ x is greater than or equal to 0.

Taking the switching unit as an N-type device, where N is 2, m is 2, and x is 1, as shown in fig. 38, the two LED arrays are respectively a first LED array LED1 and a second LED array LED2, the first LED array LED1, the second LED array LED2, and the current limiting device Q0 are sequentially disposed along the current direction, the two switching units are respectively a first switching unit Q1 (x switching units described above) and a second switching unit Q2 (the remaining m-x switching units described above), the first switching unit Q1 is coupled with the first LED array LED1, that is, both ends thereof are connected to the upstream of the current limiting device Q0, both ends of the second switching unit Q2 are respectively connected to the positive polarity end of the second LED array LED2 and the negative polarity end of the dc power supply U, and both ends thereof are respectively connected to the upstream and downstream of the current limiting device Q0.

Correspondingly, when m switching units are P-type devices, the current limiting device Q0 and the LED array corresponding to/coupled with the m switching units are sequentially arranged along the current direction, wherein two ends of x switching units are both connected to the downstream of the current limiting device Q0, and two ends of the remaining m-x switching units are respectively connected to the upstream and downstream of the current limiting device Q0, wherein x is an integer, and m is greater than or equal to x and greater than or equal to 0.

Wherein, x switch units are respectively Q1 … Qx, and m-x switch units are respectively Qx +1 … Qm.

Among them, in view of the difference in connection relationship thereof, x switching units Q1 … Qx may be referred to as floating switching units, and the remaining m-x switches among the m switching units may be referred to as common ground switching units.

When x is 0, all the m switch units are the common ground switch unit.

When x is m, all the m switch units are floating switch units.

When m > x > 0, the m switch units comprise both floating and common ground switch units.

Because the floating switch units and the current limiting devices cannot be connected in common, the floating switch units and the current limiting devices need to be isolated/insulated from each other, the integration and the manufacture are difficult, and the common ground switch units are easier to integrate and lower in cost.

Therefore, the value of x may be preferably small from the viewpoint of reducing the manufacturing cost and simplifying the manufacturing process. For example: 3 > x > 0 or 2 > x > 0, the control circuit 1 is more easily integrated in one chip in the case where the number x of floating switch cells is small, thereby obtaining a low cost advantage.

However, when there are a plurality of floating switch units and a plurality of common ground switch units, each floating switch unit only bypasses the LED array connected in parallel when conducting, and at most one of the plurality of common ground switch units can only bypass the LED array connected in parallel, and the rest of the common ground switch units collectively bypass the plurality of LED arrays when conducting, i.e. the floating switch units are arranged, so that the formation of the bypass loop of the LED arrays can be more diversified and flexible, and from this point of view, the value of x can be preferably larger, for example, m ≧ x ≧ m-1.

Wherein, x switch units in the m switch units can also be expressed as being correspondingly connected in parallel with x LED arrays in the m LED arrays, and the other m-x switch units are respectively and correspondingly bridged between one end of the other m-x LED arrays and the output end of the direct current power supply U, and can be respectively conducted so that the corresponding end of each m-x LED array can loop back to the direct current power supply U through the corresponding switch unit on the circuit structure, thereby allowing the corresponding loop current.

Specifically, the rest m-x switch units are correspondingly bridged between one ends, close to the positive pole of the direct-current power supply U, of the rest m-x LED arrays and the negative pole of the direct-current power supply U respectively.

Alternatively, the floating switch unit may be disposed alternately with the common switch unit, for example: the floating switch unit → the common ground switch unit → the floating switch unit → the common ground switch unit. Since the floating switch unit disposed upstream of the common ground switch unit in the current direction can be prevented from being bypassed by the common ground switch unit, the floating switch unit may be disposed partially or entirely upstream of the common ground switch unit in the current direction, and further preferably disposed entirely upstream of the common ground switch unit in the current direction.

In summary, based on the control circuit 1 provided in this embodiment, through the arrangement of the floating switch unit and the common ground switch unit, a person skilled in the art can select the types of the m switch units (the floating switch unit and/or the common ground switch unit), the number of the switch units of each type, and the connection relationship between the switch units of each type and the n LED arrays LED1 … LEDn and the current limiting device Q0 according to actual requirements (any one of process requirements, cost requirements, and bypass loop requirements).

EXAMPLE eleven

In this embodiment, as shown in fig. 11, when n is 2 and m is 1, the switching unit Q1 is connected in parallel to two ends of a serial body formed by connecting the corresponding LED array LED2 and the current limiting device Q0 in series. Assuming that the light emission amounts per unit power of the first LED array LED1 and the second LED array LED2 are the same under the same driving current, the turn-on voltage drop of the first LED array LED1 is V1, and the turn-on voltage drop of the second LED array LED2 is V2; the output voltage of the dc power supply U is V.

When V1+ V2> V ≧ V1, the switching unit Q1 is turned on, the branch of the second LED array LED2 and the current limiting device Q0 connected in series is bypassed, the control unit D1 controls the on-resistance of the switching unit Q1 to turn on the bypass circuit composed of the dc power supply U, the first LED array LED1 and the switching unit Q1 with a bypass circuit current I1, the power P1 of the bypass circuit is V × I1, the light emission amount L1 of the LED array is V1 × I1 × K1, and K1 is the unit power light emission amount corresponding to the LED array when driving the current I1.

The control unit D1 controls the main loop current and the bypass loop current to make PM ≈ P1, so that the output power variation of the direct current power supply does not exceed a first preset threshold value when V is larger than or equal to V1, or the LM ≈ L1 is made, so that the light emission variation of the LED array does not exceed a second preset threshold value when V is larger than or equal to V1, and the brightness variation is reduced or eliminated. In addition, the current limiting device Q0, the switching unit Q1 and the control unit D1 are partially or completely integrated in the same integrated circuit, so that the cost advantage is obvious.

Referring to fig. 16, the operation waveforms of the embodiment shown in fig. 11 are further illustrated, wherein the horizontal axis is a time axis, the vertical axis V (T) is an output voltage waveform after rectification of the ac voltage, 4-1-V1+ V2 is a sum of an on-voltage drop of the first LED array LED1 and an on-voltage drop of the second LED array LED2, a current waveform of the current limiting device Q0 corresponds to 4-1-IQ0(T), a current waveform of the switching unit Q1 corresponds to 4-1-IQ1(T), a power or light emitting amount waveform of the first LED array LED1 corresponds to 4-1-P1(T), and a power or light emitting amount waveform of the second LED array LED2 corresponds to 4-1-P2 (T).

In the TA-TB time interval on the horizontal axis, when V (t) is greater than 4-1-V1+ V2 (where "greater than" may leave a certain margin in the implementation, for example, the difference between V (t) and 4-1-V1+ V2 is greater than a small positive value), the current-limiting device Q0 is turned on by the main loop current IM, and the switching unit Q1 is turned off; in the TB-TC time interval of the horizontal axis, when V (t) is less than 4-1-V1+ V2 (here, "less than" may leave a certain margin in the implementation, for example, the difference between V (t) and 4-1-V1+ V2 is less than a small positive value), the current of the current-limiting device Q0 is zero, and the switching unit Q1 is turned on by the bypass loop current I1; this is true for each cycle and is not described in detail herein.

The following parameters are assumed: when the on voltage drop of the first LED array LED1 is 200V, the on voltage drop of the second LED array LED2 is 50V, the bypass loop current I1 is set to 50mA, and the main loop current IM is set to 40mA, then during TA-TB, the power of the first LED array LED1 is 200V 40mA 8W, the power of the second LED array LED2 is 50V 40mA 2W, and the total is 10W, during TB-TC, the power of the first LED array LED1 is 200V 50mA 10W, the power of the second LED array LED2 is zero, and the total is also 10W, that is, the sum of the powers of the first LED array LED1 and the second LED array LED1 is constant, and when the light emitting load is an LED, an approximately constant LED light emitting amount can be obtained, and stroboflash can be reduced.

In fig. 16, the switching between the main loop current and the bypass loop current is performed instantaneously, in an actual device, there may be a transition region where the switching may exist, and in the transition region, the variation processes of the bypass loop current and the main loop current are optionally controlled, so that the sum of the powers of the first LED array LED1 and the second LED array LED2 in the transition region is kept constant, and an approximately constant LED light emitting amount can be obtained, thereby reducing stroboflash, fig. 17 shows a waveform having the transition region, and fig. 18 shows a simple implementation circuit.

In fig. 17, TA1-TA2 is a first transition region, and corresponding to the time TA in fig. 16, the bypass loop current waveform 4-1-IQ1(T) drops from I1 to zero, the main loop current waveform 4-1-IQ0(T) rises from zero to IM, and the bypass loop current and the main loop current are controlled to change in association/synchronization such that the power of the first LED array LED1 drops to a value equal to the power of the second LED array LED 2; TB1-TB2 is a second transition region, corresponding to the time TB in fig. 16, where the main loop current waveform 4-1-IQ0(T) drops from IM to zero and the bypass loop current waveform 4-1-IQ1(T) rises from zero to I1, and similarly, the changes of the bypass loop current and the main loop current are controlled in relation/synchronization such that the power of the first LED array LED1 drops to a value equal to the power of the second LED array LED 2; TC1-TC2 are third transition zones, and the processes of TA1-TA2 are repeated corresponding to the TC time in FIG. 16.

In fig. 18, the ac power VSIN is rectified by the rectifier DB001 and then filtered by the parallel capacitor C001 to form a dc power, and the dc power provides the output voltage v (t) shown in fig. 16, wherein the first load 4-1-D21 corresponds to the first LED array LED1, and the second load 4-1-D22 corresponds to the second LED array LED 2.

The control circuit includes: the control unit comprises a signal reference VR001, a signal reference VR002, a comparator EA001, a comparator EA002, a resistor R001 and a resistor R002. Here, the comparators EA001 and EA002 may be operational amplifiers or amplifiers.

The first load, the second load, the current limiting device Q002, the resistor R001, the resistor R002 and the direct current power supply jointly form a main loop, current flowing through a series body formed by the resistor R001 and the resistor R002 generates first electric signals positively correlated with pulsating direct current voltage at two ends of the series body, and a comparison signal is generated between the first electric signals and a first threshold Vref1 through a comparator EA 001; when the direct current voltage is enough to drive the conduction voltage drops of the first load and the second load, for example, the direct current voltage value is far larger than the sum of the conduction voltage drops of the first load and the second load, the voltage of the first electric signal is equal to Vref2 and larger than Vref1, the comparison signal output by EA001 is a low level signal, the field effect tube Q001 is driven to be cut off, and the driving circuit operates in a main loop formed by a direct current power supply, the first load 4-1-D21, the second load 4-1-D22, the field effect tube Q002, a resistor R001 and a resistor R002; when the dc voltage is not sufficient to drive the conducting voltage drops of the first load and the second load, it is referred to as: the voltage of the first electric signal is smaller than Vref1 in the first voltage interval, the comparison signal output by EA001 is a high level signal, the field effect tube Q001 is driven to be conducted, and the driving circuit is switched to a bypass loop formed by a direct current power supply, the first load 4-1-D21, the field effect tube Q001 and a resistor R001; in the time interval from T0 to TA1 and the time interval from TB2 to TC1, the current of the current-limiting device Q002 is zero, the field effect transistor Q001 is conducted, and the current value is as follows: vref1/R001, Vref1 is the output voltage of signal reference VR 001; in the time interval TA2-TB1, the current-limiting device Q002 is turned on, the sub-switch Q001 is turned off, the main loop current has a value of Vref2/(R001+ R002), and Vref2 is the output voltage of the signal reference VR 002.

In a time range corresponding to the first transition zone TA1-TA2, the current of the sub-loop is decreased from Vref1/R001 to zero, and the current of the main loop is increased from zero to Vref2/(R001+ R002); in a time range corresponding to the second transition region TB1-TB2, the current of the main loop is reduced from Vref2/(R001+ R002) to zero, and the current of the sub-loop is increased from zero to Vref 1/R001; in the two transition regions, the comparator EA0001 outputs an intermediate voltage signal having an amplitude between the high level signal and the low level signal.

Vref2 is configured to be slightly larger than Vref1 to turn on the current limiting device Q002 and the main loop in preference to the sub-switching unit Q001 and the bypass loop, or to configure the input offset voltage of the amplifiers EA001 and/or EA002 to achieve the same effect.

By making the ratio of Vref1/R001 to Vref2/(R001+ R002) substantially equal to the quotient of the conduction voltage drop of the first load 4-1-D21 and the conduction voltage drop of the second load 4-1-D22VTH divided by the conduction voltage drop of the first load 4-1-D21, configuring Vref2 to be slightly greater than Vref1, it can be achieved that at any time in the transition region and the non-transition region, or in other words, before the main loop and the shunt loop are switched, the sum of the powers of the first load and the second load during and after the switching process is maintained substantially constant, further, the sum of the powers or the sum of the fluxes corresponding to the LED arrays that are switched on is substantially constant, and, during the switching process, the powers of the LED arrays are dynamically adjusted such that the power drop of a portion of the LED arrays is compensated or offset by the increase of the power of another portion of the LED arrays.

Example twelve

The present embodiment is optimized based on some embodiments described above.

When m > x > 0, that is, when both the floating switch unit and the common ground switch unit are provided in the control circuit, as shown in fig. 33, there is provided a package frame structure provided with a first base island a and a second base island B which are adjacently disposed and insulated from each other, and the floating switch unit and the common ground switch unit of the control circuit 1 are respectively disposed on different base islands.

Wherein, the first base island A and the second base island B can be insulated from each other by a spacing arrangement or isolated by an insulating material.

Wherein, the base island can be made of metal, and the commonly used metal is copper or iron.

The first base island a and the second base island B are disposed in a main frame (not shown).

The first base island A and the second base island B respectively comprise no less than four edges, and referring to any base island, the four edges are respectively: the adjacent edge that sets up adjacently, with adjacent edge relative set up deviate from the limit and two pin limits of relative setting.

Two pin edges of the first base island A and the second base island B are respectively provided with a pair of rib claws, namely a first rib claw C and a second rib claw D which are arranged on the first base island A, and a fourth rib claw C 'and a fifth rib claw D' which are arranged on the second base island B, wherein the rib claws can be configured into pins of a frame structure.

The arrangement of a pair of rib claws on the two pin edges improves the encapsulation stability of the first base island A and the second base island B.

Preferably, a third rib claw E is arranged on the deviating edge of the first base island a, a sixth rib claw E 'is arranged on the deviating edge of the second base island B, and the third rib claw E and the sixth rib claw E' are arranged, so that the encapsulation stability of the first base island a and the second base island B is further improved.

Preferably, the included angle between each rib claw and the edge where the rib claw is located is 90 degrees, and the packaging stability of the base island can be improved by the arrangement.

Optionally, the fingers are generally disposed on two opposite sides of the base island and integrally formed with the base island, and a pair of fingers extends to the outside of the molding compound and can increase the stability of the corresponding base island package. The frame structure is usually in the form of a single base island, the single base island is fixed by a pair of rib claws arranged at two ends, the pair of rib claws is usually arranged corresponding to the positions of a third rib claw E and a sixth rib claw E 'in fig. 33, the two rib claws have stress towards the end parts respectively, and after the fixed sealing, the function of stabilizing the base island is achieved, but because the frame structure in the embodiment is a double-base island structure, the stability of the first base island a and the second base island B cannot be maintained only by arranging the third rib claw E and the sixth rib claw E', and the embodiment ensures that the frame structure of the double-base island is still stable by arranging the pair of rib claws on two pin edges.

In this embodiment, the third rib claw E and the sixth rib claw E' are not provided, and the stability of the frame structure of the double-base island can be ensured.

In other embodiments of this embodiment, a plurality of pairs of claws may be disposed on two lead edges as required.

In addition, the fingers may be configured as pins of a frame structure, specifically, in this embodiment, a pair of fingers on the side of the pin of the first base island a is configured as the second pin 20 and the seventh pin 10, respectively, and a pair of fingers on the side of the pin of the second base island B is configured as the third pin 40 and the sixth pin 30, respectively.

Preferably, the frame structure further comprises a plurality of separation pins, the separation pins are arranged around the base island and electrically connected with the devices on the first base island A and the second base island B through metal connecting wires.

Specifically, taking a frame structure designed to have eight pins as an example, refer to fig. 33, where eighth pin 50 is disposed between third claw E and first claw C, first pin 60 is disposed between third claw E and second claw D, fifth pin 70 is disposed between fourth claw C 'and sixth claw E', and fourth pin 80 is disposed between fifth claw D 'and sixth claw E'. The first pin, the fourth pin, the fifth pin and the eighth pin are not directly connected with the base island, the direct connection mentioned herein refers to an integrally formed connection or other mechanical connection mode, and each pin can be electrically connected with other structures (such as the base island) in the frame structure in a wire bonding mode during packaging. Of course, any one of the first pin, the fourth pin, the fifth pin and the eighth pin may also be connected to the base island according to actual requirements.

Specifically, taking m ═ n ═ 2 as an example, the correspondence relationship between the control circuit 1 and the frame structure when it is designed as a chip by integration will be described with reference to fig. 38. In fig. 38, the first switch unit Q1 is a floating switch unit, the second switch unit Q2 is a common ground switch unit, the LED arrays are respectively a first LED array LED1 and a second LED array LED2, which are connected in series with the dc power supply U and the current limiting device Q0 to form a main circuit, and the switch units are respectively a first switch unit Q1 connected in parallel with the first LED array LED1 and a second switch unit Q2 connected in parallel with both ends of a branch of the series connection formed by the second LED array LED2 and the current limiting device Q0.

In general, chips having a common potential can be placed on the same base island, and in the control circuit 1 shown in fig. 38, since a potential difference exists between the negative polarity terminal of the first switch unit Q1 and the negative polarity terminal of the second switch unit Q2, it is difficult for the first switch unit Q1 and the second switch unit Q2 to be simultaneously manufactured on a chip having only one substrate, and it is also difficult for the first switch unit Q1 and the second switch unit Q2 to be simultaneously placed on the same base island when they are respectively manufactured as two chips.

The method adopted in the embodiment is as follows: the first switching unit Q1 (or other device having a common potential with its cathode, for example, a part of the control unit D1) is fabricated as a chip, and placed on a base island; and, the second switching unit Q2, the current limiting device Q0, and the control unit D1 (or another portion of the control unit D1) are manufactured as another chip and placed on another base island, thereby allowing the first switching unit to be integrated with the second switching unit in the same package, overcoming the limitation of the structure using a single base island, and further reducing the package size when the control circuit 1 is implemented as an integrated circuit.

Specifically, with respect to fig. 38, it is possible to configure: the positive polarity terminal of the first switching unit Q1 is connected to the first pin 60, and the negative polarity terminal is connected to the second pin 20; the positive polarity terminal of the second switching unit Q2 is also connected to the second pin 20, the negative polarity terminal is connected to the third pin 40, the positive polarity terminal of the current limiting device Q0 is connected to the fourth pin 80, that is, the first switching unit Q1 and the second switching unit Q2 are disposed at the first base island a and the second base island B, respectively, and the current limiting device Q0 is also disposed on the second base island B.

Alternatively, as in fig. 39, the difference compared to fig. 38 is that: there is no direct connection (shown in phantom) between first LED array LED1 and second LED array LED2 in fig. 39.

With regard to fig. 39, in conjunction with fig. 33, it is also possible to configure that the first switching unit Q1 and the second switching unit Q2 are respectively disposed on the first base island a and the second base island B, and the current limiting device Q0 is also disposed on the second base island B, and the positive polarity terminals of the first switching unit Q1, the second switching unit Q2, and the current limiting device Q0 are respectively connected to three of the first pin, the fourth pin, the fifth pin, and the eighth pin.

In other embodiments corresponding to the second embodiment and the third embodiment, the following is preferable: the current limiting device Q0 and the portion of the control unit D1 having a common potential with the negative polarity terminal of the second switching unit Q2 are disposed in the second base island B, and the portion of the control unit D1 having a common potential with the negative polarity terminal of the first switching unit is disposed in the first base island a. It should be noted that "common potential" herein includes, but is not limited to, zero potential difference, and may also refer broadly to a potential difference that is relatively low, such as a potential difference that does not exceed a PN junction turn-on threshold, to avoid the integrated circuit from entering an undesirable latched or locked-up state (latchup). In addition, for example, in the control circuit 1 in which two floating switch cells and one or more common switch cells are provided, it is necessary to provide a base island for each of the two floating switch cells and a base island for each of the one or more common switch cells, and to insulate the three base islands from each other. That is, the person skilled in the art can know based on the present embodiment: each time a floating switch unit is added to the control circuit 1, a new base island insulated from other base islands is preferably added.

EXAMPLE thirteen

The present embodiment is further optimized on the basis of the above embodiments, and further includes at least one current programming interface, where the current programming interface is disposed in a circuit corresponding to the current limiting device or the current source in the corresponding bypass loop, and belongs to a part of the current source in the current limiting device or the corresponding bypass loop, so as to set a current of a loop in which the current source in the current limiting device or the bypass loop is located, or a current of an LED array that is turned on in the n LED arrays.

For example, the current programming interface is configured to receive a first resistance that is operatively connected from the periphery. The current regulation performance of the current source in the main loop and/or the bypass loop can be controlled by the first resistor, and further, the current or the power in the corresponding main loop/bypass loop can be limited/regulated. Further alternatively, the current programming interface may include two pins disposed externally, in combination with the fifth pin 70 and the sixth pin 30 of the dual-base island frame shown in fig. 33, so that when a user uses an integrated circuit implemented by the control circuit of the present invention to manufacture a lighting device/lamp, a resistor with a certain resistance value may be connected between the fifth pin 70 and the sixth pin 30 according to requirements such as power, so as to set the current/power in the main loop/bypass loop, and the power of the lamp may be configured in a customized manner in a lighting device manufacturing process. In addition, it can be understood that: the sixth pin 30 is connected integrally with the second base island B, directly to the substrate of the chip arranged thereon or in a conductive material or by wire bonding, and thus can serve as a ground for the common ground switching unit or the ground for the control unit, in which case only one pin, for example the fifth pin 70, is required, cooperatively (or as the sixth pin 30), together receiving the first resistor to be operatively connected from the periphery.

Specifically, when designing an integrated circuit/chip, the integrated circuit/chip peripheral circuit may include only one of the aforementioned current programming interfaces, and the power of the driving circuit or the lighting device is set by connecting an external resistor.

Alternatively, for an already designed integrated circuit, most of the devices and connections between the devices therein are fixed, i.e., the functions of the integrated circuit are defined by the already designed integrated circuit, however, it is generally more desirable for the integrated circuit, whether the user of the integrated circuit or the designer of the integrated circuit, to meet the requirements of as many applications as possible, in order to maximize the commercial value. A more common method for solving such problems is to reserve a port for the integrated circuit, configure an external device at the reserved port by a user, and program analog signals or digital logic and the like inside the integrated circuit to a limited extent, so as to achieve a desired effect, for example, in the design of the driving circuit, change the power of the driving circuit by connecting the reserved port with the external device, and the like; in addition, due to the limitation of the semiconductor process adopted by the integrated circuit, some electrical signals with higher amplitudes, energy signals, negative signals or floating signals are difficult to integrate and have higher cost, and at this time, a port needs to be reserved for the integrated circuit, and after the signals are processed by an external circuit, the external circuit is connected with the reserved port of the integrated circuit through hardware.

The circuit block CC1 shown in fig. 31 is a commonly used current source circuit, and includes a common terminal GND and a current terminal OUT, the circuit block CC1 includes a voltage reference XVR, an amplifier XEA and a field effect XQ, a current of the current terminal OUT is equal to a voltage of the voltage reference XVR/a resistance RK, and a current value corresponding to the current terminal OUT is changed by changing a resistance value of the resistance RK; the circuit module CC2 shown in fig. 32 is a modification of the circuit module CC1, and one difference is that the circuit module CC2 further includes a current mirror XM, the current of the current port OUT is equal to the voltage of the voltage reference XVR and the amplification factor of the current mirror XM/the resistance RK, and changing the resistance of the resistance RK changes the current value corresponding to the current port OUT.

Both the current source circuits in fig. 31 and fig. 32 include a resistor for setting a current at a current end, and have at least one current end, and actually, the current source may also adjust the current at a plurality of current ends through one resistor in cooperation, which is not described in detail herein. Since the user of the lighting device usually needs to adjust the brightness of the LED current/lighting load according to actual needs, the integrated circuit designed based on the solution of the present invention may not include the resistor RK in fig. 31 and fig. 32, but reserve the current programming interface, such as the K1 port and the K2 port in fig. 31 and fig. 32, and usually, the K2 port is shared with the common terminal (ground). For example, the R001 resistor in fig. 18 may not be designed inside the integrated circuit, and two ends of the R001 resistor may be used as the K1 port and the K2 port, so as to change the resistance of the R001, and change the power or the light emitting brightness of the driving circuit or the lighting device, as well as the R002 resistor in fig. 18, which is not described again.

Example fourteen

This embodiment is further optimized on the basis of some embodiments described above, in this embodiment, the dc power supply U is capable of outputting a pulsating voltage, and the control unit D1 is configured to: and regulating the current in the conducted at least one switch unit to change in a reverse direction with the output voltage of the direct current power supply U or the voltage borne by the n LED arrays.

In other words, the current flowing through the LED array or arrays in the n LEDs that are in the conducting state, or in the bypass loop, is dynamically adjusted by the conducting switching unit or units and/or the current limiting device Q0, so as to vary in the opposite direction/negative relation to the voltage experienced by the LED array or arrays in the main/bypass loop.

In particular, the control unit D1 is further configured to: reducing the current in the LED array which is turned on in the n LED arrays with the increase of the output voltage of the dc power supply U/the voltage born by the n LED arrays, or increasing the current in the LED array which is turned on in the n LED arrays with the decrease of the output voltage of the dc power supply U/the voltage born by the n LED arrays; thus, adjusting the power of the n LED arrays remains within a neighborhood of the first power value.

The first power value may be set according to the specific needs of the specific implemented goods or the specific needs of the user, for example, the design specification of the goods requires that the temperature of the LED device used by the goods is not more than 100 ℃ to meet the life of the goods, and the luminous flux is not less than 1000 lumens to meet the lighting effect of the goods, so that the designer of the goods needs to select a suitable LED or LED combination, and the power of the LED or LED combination is controlled to meet the above design specification.

The control unit D1 can obtain a first electrical signal reflecting the output voltage of the dc power source U. For example, the first electrical signal may be derived from one of: i) the voltage endured by the n LED arrays, or ii) the difference between the output voltage of the dc power supply U and the voltage endured by the n LED arrays.

The first electrical signal may be positively or negatively correlated with the output voltage of the direct current power supply U, and when the first electrical signal is positively correlated with the output voltage of the direct current power supply U, the control unit D1 is further configured to: and controlling at least one of the m switching units to be turned on to establish a bypass loop in response to the first electric signal being less than a first threshold value, and controlling at least one of the m switching units to be turned off to switch to other bypass loops or main loop operation in response to the first electric signal being greater than or equal to the first threshold value.

When the first electric signal is negatively correlated with the output voltage of the direct current power supply U or the voltage born by the n LED arrays or the difference value of the output voltage of the direct current power supply U and the voltage born by the n LED arrays, at least one of the m switch units is controlled to be switched on to establish a bypass loop in response to the first electric signal being larger than a first threshold, and at least one of the m switch units is controlled to be switched off to be switched to other bypass loops or main loop to operate in response to the first electric signal being smaller than or equal to the first threshold.

For simplicity, the first electrical signal is positively correlated with the output voltage of the dc power source U.

Alternatively, in some embodiments, the first electrical signal may be taken from both ends of the dc power source, or may be obtained by a circuit coupled to the positive and negative polarity output terminals of the dc power source.

Optionally, in the control circuit in some embodiments, in a state where at least one of the switching units is turned off, the first electrical signal may be acquired based on one or more circuit parameters in the control circuit. For example, the first electrical signal may be taken from at least one of a voltage across the current limiting device, a voltage at a control terminal of the current limiting device, and a current of the current limiting device. Optionally, in the control circuit in some embodiments, in a state where the at least one switching unit is turned on, the first electric signal is taken from at least one of a voltage across the current limiting device, a voltage at a control terminal of the current limiting device, and a current of the current limiting device. The control unit of the control circuit is configured to determine, by the first electrical signal: i) whether the dc voltage is sufficient to turn on all n LED arrays, or ii) the magnitude of the dc voltage relative to the full brightness threshold.

Alternatively, in the control circuit in some embodiments, the first electrical signal may be taken from both ends of at least one common ground switch.

The control unit D1 is provided with an electrical signal measurement unit to obtain the first electrical signal, and specifically, the electrical signal measurement unit is coupled to the control circuit to obtain the first electrical signal, and the specific method includes:

1) the output voltage of the direct current power supply U is collected; or,

2) the current-limiting device is coupled to two ends of a resistor or an MOS (metal oxide semiconductor) tube (such as a current-limiting device) positioned on the main loop/bypass loop, and the difference between the output voltage of the direct-current power supply U and the conduction voltage drop of the n LED arrays is acquired; or,

3) the LED array is coupled to two ends of at least one LED array which is connected in series with the main loop, and the voltage borne by the LED array is collected.

Typically, implemented in an integrated circuit, the first threshold may be one or more reference voltages or reference voltages, or one or more reference currents or reference currents. The first threshold corresponds to one of the following seven: i) a value of the first electrical signal reflecting a minimum voltage of the dc power supply sufficient to turn on all of the n LED arrays; ii) a reference voltage value that differs from the minimum voltage value by a constant positive value; iii) a voltage value of the DC power supply at which luminous fluxes of the LEDs in the n LED arrays reach a predetermined value; IV) minimum voltage value sufficient to turn on the DC power supply for the n LED arrays; v) a value of a first electrical signal reflecting a voltage value of the dc power supply when the luminous flux of the n LED arrays reaches a predetermined value; VI) a value of a first electrical signal reflecting a minimum voltage of the dc power supply when a luminous flux generated by the voltage/current/power across the n LED arrays reaches a predetermined value; VII) just enough dc voltage value to turn on all of the n LED arrays. The predetermined value may be set to a luminous flux when a voltage sufficient to turn on the n LED arrays is applied across the n LED arrays, or may be set to another value as necessary, for example, a luminous flux when a voltage sufficient to turn on the n-1 LED arrays is applied across the n LED arrays.

In particular, the predetermined value is dictated by the embodied commodity, typically a prescribed luminous flux value, such as 1000 lumens.

In conjunction with fig. 7 and table two, the first threshold may also be set to multiple thresholds, for example, corresponding to the first bypass loop.

Next, referring to fig. 7, an operation process of the driving circuit 2 is described, where the driving circuit 2 is configured to drive three LED arrays, the three LED arrays are respectively a first LED array LED1, a second LED array LED2, and a third LED array LED3, the three switching units, namely, the first switching unit Q1, the second switching unit Q2, and the third switching unit Q3, are respectively connected in parallel with the three LED arrays, and the dc power supply U, the current limiting device Q0, and the three LED arrays together form a main circuit of the driving circuit 2.

Taking the example that the first electrical signal acquires the output voltage of the dc power supply U, the smaller the value of the first electrical signal is, the lower the output voltage of the dc power supply U is reflected, that is, the first electrical signal is positively correlated with the output voltage of the dc power supply U.

Wherein the first threshold is set as: a value of the first electric signal reflecting a voltage value of the direct current power supply when the luminous fluxes of the three LED arrays reach a predetermined value. And controlling at least one of the three switch units to be conducted to establish a bypass loop in response to the first electric signal being smaller than a first threshold value, so that part of the LED arrays (one or two LED arrays) are conducted, and switching all of the three switch units to be switched to the main loop operation in response to the first electric signal being larger than or equal to the first threshold value.

Optionally, when the first threshold is set corresponding to the sum of the conduction voltage drops of the three LED arrays, at this time, in response to the first electrical signal being smaller than the first threshold, at least one of the three switch units is controlled to be conducted to establish a bypass loop, so that part of the LED arrays (one or two LED arrays) are conducted. In response to the first electrical signal being greater than or equal to the first threshold, all three switching units are turned off to switch to main loop operation. The control unit D1 is further configured to: and adjusting the first bypass current flowing through the switched-on at least one switching unit to be larger than the current value flowing through the three LED arrays when all the three switching units are switched off, so that the product of the voltage borne by the three LED arrays and the first bypass current is kept in the neighborhood of the first power value.

The first threshold may be configured differently according to the number of LED arrays in the control circuit or the coupling structure, and may also be affected by the voltage drop of some devices in the driving circuit, for example, the impedance or voltage drop of the current limiting device Q0 connected in series in the main loop.

It should be noted that, in this embodiment, conduction voltage drops of three LED arrays are taken as an example, and when conduction voltage drops of three LED arrays are different from each other, the conduction voltage drops may be sorted according to the magnitude of the conduction voltage drops, and the switching operation may be performed in a plurality of sub-loops that are only connected to one LED array.

It is noted that, driven by the control circuit 1, when the output voltage of the dc power source U is at any voltage level (possibly constant) lower than the full-on threshold/the first threshold, a plurality of subsets (for example, the first subset includes the first LED array LED1 and the second LED array LED2, and the second subset includes the first LED array LED1 and the third LED array LED3) corresponding to the voltage level can be cyclically turned on or turned on in turn. The cyclic lighting or the alternate conduction here is actively initiated under the control of the control unit D1.

In the present embodiment, different portions of the three LED arrays, such as the first subset and the second subset, are alternately/alternately turned on in a low voltage interval (a voltage interval having a lower voltage and insufficient to turn on the three LED arrays) of the dc power supply U, while generally the low voltage interval cannot support the serial conduction of the LED arrays in the union of the first subset and the second subset, and optionally the first subset and the second subset are both characterized by: when the LED array is positioned in a low-voltage interval, the DC power supply U can conduct the maximum number of LED arrays. Alternatively, the number of LED arrays in the union of the first subset and the second subset is greater than the (e.g., maximum) number of LED arrays that the dc power supply can conduct in the low voltage interval. To this extent, the electric energy provided by the dc power supply U in the low voltage region is released/converted into light energy by a larger number of LED arrays, which also results in better energy conversion efficiency and a larger LED light emitting surface, improving the illumination performance to a certain extent.

Optionally, the number of LED arrays in the first subset is the same as the number of LED arrays in the second subset, which results in that the light energy released by the larger number of LED arrays forms a relatively constant light emitting area, in other words, the LED arrays of the two subsets generate two powers/luminous fluxes which are closer to each other, to a certain extent inhibiting the improvement of the lighting effect.

Preferably, the union of the first subset and the second subset covers three LED arrays (in other embodiments, a plurality of LED arrays are possible), so that the LED light emitting area can be kept unchanged during the change from the normal voltage interval (the interval sufficient to turn on three LED arrays) of the dc power supply U to, for example, the first voltage interval (insufficient to turn on three LED arrays) with a lower voltage value, thereby improving the lighting performance. In other words, the power of the three LEDs is kept substantially constant in combination with the current regulation means, and the three LED arrays always generate stable power/luminous flux with the maximum possible light emitting area, thereby further improving the lighting effect.

Alternatively, the LED arrays in the subsets that are alternately switched on, such as the first subset and the second subset, may not be identical, and there may or may not be an intersection between the two.

Optionally, the number of LED arrays in the union of the LED arrays in the first bypass loop and the LED arrays in the second bypass loop is greater than the maximum number of LED arrays that can be turned on by the dc power supply when the first electrical signal is smaller than the first threshold.

Optionally, if the conduction voltage drop of the LED array located in the first bypass loop is larger than the conduction voltage drop of the LED array in the second bypass loop, the control unit D1 is further configured to: adjusting the current in the second bypass loop to be larger than the current in the first bypass loop, so that the relative rate of change between the powers of the LED array in the second bypass loop and the LED array in the first bypass loop is smaller than a first predetermined percentage, or the relative rate of change of the powers of the two during switching is smaller than a first predetermined percentage, the first predetermined percentage being as small as possible, for example, a value smaller than 5%; alternatively, if the conduction voltage drop of the LED array in the first bypass loop is substantially equal to the conduction voltage drop of the LED array in the second bypass loop, the control unit D1 is further configured to: the rate of change of the current in the second bypass loop relative to the current in the first bypass loop is adjusted to not exceed a first predetermined percentage such that the power of the LED array in the second bypass loop is substantially the same as the power of the LED array in the first bypass loop, or the relative rate of change of the power of the LED array in the second bypass loop and the power of the LED array in the first bypass loop during switching is less than a first predetermined percentage, which is as small as possible, for example, a value less than 5%.

Optionally, the control unit D1 is further configured to: the current drop in the first part of the switch units switched from on to off state and the current rise in the second part of the switch units switched from off to on state are synchronously controlled, so that the sum of the powers of the two LED arrays in the loop in which the first part of the switch units and the second part of the switch units are located is basically constant, or the sum of the powers of the two LED arrays is basically constant, and further the luminous power/luminous flux of the two LED arrays is controlled to be basically constant or kept within the neighborhood of a predetermined value of the first luminous flux, for example, within the neighborhood of +/-5% or even smaller of the predetermined value of the first luminous flux.

In this embodiment, the conducting switch units in the first bypass circuit are defined as the first part of switch units, and the conducting switch units in the second bypass circuit are defined as the second part of switch units.

Optionally, the control unit D1 is further configured to: during the transition when a plurality of switching units are switched,

Optionally, the control unit D1 is further configured to: during the transition in switching between the first bypass loop and the second bypass loop, i) synchronously controlling the current in the first bypass loop to decrease with increasing second bypass loop current, such that the power drop of the LED array in the first bypass loop is compensated/cancelled by the power increase of the LED array in the second bypass loop; and the number of the first and second groups,

ii) synchronously controlling the current in the first bypass loop to increase as the current in the second bypass loop decreases such that the power drop of the LED array in the second bypass loop is compensated/counteracted by the power increase of the LED array in the first bypass loop.

Optionally, the control unit D1 is further configured to: in the transition process of switching on from the second part of switch units to the first part of switch units, controlling the current in the first part of switch units to increase synchronously before the descending amplitude of the current in the second part of switch units relative to the descending amplitude before the transition process begins exceeds a preset amplitude; and/or in the transition process of switching conduction from the first part of switch units to the second part of switch units, controlling the current in the second part of switch units to increase synchronously before the descending amplitude of the current in the first part of switch units relative to the descending amplitude before the transition process begins exceeds a preset amplitude; wherein the preset amplitude is an arbitrary value less than 5%.

The above-mentioned embodiments of the switching process between the first bypass loop and the second bypass loop are also applicable to the main loop and any one of the bypass loops, and are not described in detail.

Example fifteen

This embodiment is further optimized on the basis of some of the above embodiments, the LED array control method of some of the embodiments of the present invention or step SA-2) or similar steps therein, and the sub-steps of these steps may further include any one of the following 4 sub-steps including two alternative sub-steps SA-2-a) or two alternative sub-steps SA-2-b):

The first voltage interval has a voltage range below a full bright threshold. Of course, it is not excluded that a second voltage interval is also provided, below the lower limit of the first voltage interval (or may be referred to as a first bypass threshold), or lower. In other words, the first voltage interval may be defined by both the full bright threshold and the first bypass threshold as an upper limit (upper bound) and a lower limit (lower bound) of the first voltage interval, respectively. And entering a first voltage interval if the voltage of the direct current power supply is between the full brightness threshold and the first bypass threshold. In other words, the voltage of the dc power supply falls below the full bright threshold into a first voltage interval, and if the dc voltage continues to fall below the full bright threshold, into a second voltage interval lower than the first voltage interval. Correspondingly, the method of some embodiments of the present invention defined by the first voltage interval, the at least one voltage interval, may also be defined by steps based on a plurality of thresholds, such as the full bright threshold, the first bypass threshold, and the like. The applicant reserves the right to divide, actively modify, continue, and partially continue applications for these more varied variations.

Step SA-2-a) further comprises the sub-steps of:

SA-2-a-1) alternately/alternately turns on the first and second portions of LED arrays for the duration of the first voltage interval.

Step SA-2-b) further comprises the sub-steps of:

Of course, alternatively, in two different first voltage intervals a and b occurring successively in the first ripple period described above, only the first part of the LED array may be turned on, and in two first voltage intervals occurring in the subsequent second ripple period, only the second part of the LED array may be turned on, in which case the frequency of the cyclic conduction of the first part and the second part of the LEDs may be considered to be less than the frequency of the ripple dc voltage of the dc power supply. Further alternatively, in the single first voltage interval a in the first pulse period, the first partial LED array and the second partial LED array may be turned on alternately for a plurality of times (for example, hundreds of times), and the alternating frequency thereof is greater than the frequency of the pulsed dc voltage of the dc power supply.

Specifically, as shown in fig. 19A, there is provided a control circuit 01A, a drive circuit 08A, wherein m is 2 and x is 1, the control circuit 01A including a floating-ground switching unit SW21, a common-ground switching unit I21, a current limiting device I22, and a control unit 05A; the cathode of the common ground switch unit I21, the cathode of the current limiting device I22 and the cathode of the direct current power supply V21 are connected; the cathode of the floating switch unit SW21 is connected with the anode of the common ground switch unit I21, and the anode of the common ground switch unit I21, the anode of the current limiting device I22 and the anode of the floating switch unit SW21 are connected with the first load D21 and the second load D22.

The control unit 05A includes an electric signal measuring unit 02A and a timing logic circuit 06A; the input terminal of the electrical signal measuring unit 02A is coupled to the positive pole of the dc power supply to obtain a first electrical signal related to the dc voltage V21, the electrical signal measuring unit 02 further includes a comparator (not shown), one input terminal of the comparator is configured with a first threshold, the other input terminal of the comparator is configured to receive the first electrical signal, and the comparison of the first electrical signal with the first threshold generates a comparison signal reflecting the magnitude relationship between the first electrical signal and the first threshold, where the comparator may also adopt an amplifier or other circuit or device capable of reflecting the magnitude relationship between the two signals.

Usually, the comparison signal is a high level signal or a low level signal, or further includes an intermediate level signal between the high level signal or the low level signal, and the intermediate level signal is usually used for controlling the transition process between the main loop and the bypass loop, and between the bypass loop and the bypass loop. Here, the comparator may be an amplifier or an operational amplifier.

Optionally, the control terminal of at least one switching unit is connected to the output terminal of the comparator in the electrical signal measuring unit 02A and is capable of bypassing/de-bypassing the corresponding load based on the comparison signal.

Alternatively, the timing logic circuit 06A is a circuit or a device having a timing function/time delay function, such as an oscillation circuit, a frequency generation circuit, a clock generation circuit, etc., an input terminal of the timing logic circuit 06A is connected to the electrical signal measuring unit 02, and an output terminal of the timing logic circuit 06A is connected to a control terminal of the common ground switching unit I21, a control terminal of the floating ground switching unit SW21, and a control terminal of the current limiting device I22; when the voltage of the dc power supply V21 is not enough to drive the two loads D21 and D22 connected in series to reach the desired luminous flux, or the voltage of the dc power supply V21 is below the full bright threshold, for convenience of illustration, in this embodiment, a voltage interval below the full bright threshold is defined as a first voltage interval, and the timing logic circuit 06A generates two alternate time signals corresponding to a first predetermined frequency in response to the comparison signal, respectively a first time signal and a second time signal, so as to control the two bypass loops formed by the floating switch unit SW21 turning on and the common ground switch unit I21 turning off and the floating switch unit SW21 turning off and the common ground switch unit I21 turning on to alternately turn on respectively corresponding to the two time signals.

Alternatively, the control unit 05A can also control the currents of the common ground switch unit I21 and the current limiting device I22 through the timing logic circuit 06A, so that when the voltage of the dc power source V21 is in the first voltage interval, the currents of the two bypass loops are both greater than the current of the main loop, and specifically, the current regulation of the two bypass loops can be realized by controlling the signal amplitudes of the control terminals of the current limiting device I22, the common ground switch I21 and the floating switch SW21 according to the corresponding state of the timing logic circuit.

In practical applications, the electrical signal measuring unit 02A, the timing logic circuit 06A, the common ground switch I21 and the current limiting device I22 in the control circuit 01A can be easily integrated on the same chip, and the floating switch SW21 is limited to have a higher level at its negative polarity end and the level is floating with respect to the ground, so that the integration difficulty is high, therefore, the control circuit 01A can be respectively placed on two different base islands to manufacture a finished integrated circuit by adopting the aforementioned dual-base island framework, or the current setting of the common ground switch unit I21 and the current limiting device I22 in the control circuit 01A can be realized by setting a current programming interface according to the requirements of practical applications.

In fig. 19A, the driving circuit 08A includes not only the driving control circuit 01A, but also the dc power supply V21, the first load D21, and the second load D22, and the dc power supply V21, the first load D21, the second load D22, and the current limiting device I22 are sequentially connected in series to form a closed circuit.

Specifically, the first load D21 is connected in parallel across the floating switch unit SW 21; the anode of the common ground switch unit I21 is connected to the connection point of the first load D21 and the second load D22, and the cathode of the second load D22 is connected to the anode of the current limiting device I22.

The control unit 01A controls the floating switch unit SW21 and the common ground switch unit I21 to be in different on, adjustment or off states, so as to form three different energy loops, which are respectively:

in the first case: when the voltage of the dc power source V21 is greater than the sum of the turn-on voltage drop of the first load D21 and the turn-on voltage drop of the second load D22, the floating switch unit SW21 and the common ground switch unit I21 are both turned off, so as to form a third energy loop: the dc power supply V21 → the first load D21 → the second load D22 → the current limiting device I22 → the dc power supply V21, which supplies power to the first load D21 and the second load D22, and the third power loop, i.e., the main loop.

In the second case: when the voltage of the direct current power supply V21 is smaller than the sum of the conduction voltage drop of the first load D21 and the conduction voltage drop of the second load D22 and is larger than the larger value of the conduction voltage drop of the first load D21 and the conduction voltage drop of the second load D22, the floating switch unit SW21 and the common ground switch unit I21 are controlled to be alternately switched at a first preset frequency between a first state and a second state, wherein the first state is that the floating switch unit SW21 is turned off, the common ground switch unit I21 is turned on, and a first energy loop is formed: the dc power supply V21 → the first load D21 → the common ground switch unit I21 → the dc power supply V21, which supplies power to the first load D21; the second state is that the floating switch unit SW21 is turned on, the common ground switch unit I21 is turned off, and a second energy loop is formed: the dc power supply V21 → the floating ground switch unit SW21 → the second load D22 → the current limiting device I22 → the dc power supply V21, which supplies power to the second load D22.

In this embodiment, when the voltage of the dc power source V21 is greater than the sum of the conduction voltage drops of the first load D21 and the second load D22, the energy circulation path is a third energy loop to provide energy to the first load D21 and the second load D22 simultaneously, so as to obtain higher efficiency; when the voltage of the direct current power supply V21 is smaller than the sum of the conduction voltage drops of the first load D21 and the second load D22 and larger than the larger value of the conduction voltage drop of the first load D21 and the conduction voltage drop of the second load D22, the energy circulation path alternately becomes a first energy loop and a second energy loop, and alternately supplies energy to the first load D21 and the second load D22.

Taking the first load D21 and the second load D22 as LED arrays as an example, that is, the first load D21 is a first LED array, the second load D22 is a second LED array, and the driving circuit 08A is arranged such that the currents of the common ground switching unit I21 and the current limiting device I22 in the second case are greater than the current of the current limiting device I22 in the first case, so that the total powers of the first LED array D21 and the second LED array D22 are approximately equal when the dc voltages V21 are different; and when the driving circuit 08A operates in the third energy loop, the driving control circuit 01 controls the current of the current limiting device I22 to be reduced along with the increase of the voltage or the voltage average value of the direct current voltage V21 through a first electric signal reflecting the direct current voltage V21 so as to obtain that the output power of the direct current voltage V21 is approximately constant when the direct current voltage V21 fluctuates within a certain range.

Optionally, the first predetermined frequency is less than 5000 kHz.

Alternatively, the first predetermined frequency, which is substantially equal in value to the frequency of the alternating/rotational conduction of the plurality of switching units (the floating ground switching unit SW21 and the common ground switching unit I21) and the corresponding plurality of bypass loops (the first bypass loop and the second bypass loop) or the plurality of portions of the LED array controlled by the timing logic circuit 06A, may be set to any value of [0.5kHz,50kHz ] or any value of [0.5kHz,5kHz ], [5kHz,10kHz ], [20kHz,40kHz ], [60kHz,100kHz ], [100kHz,500kHz ], [10kHz,50kHz ] frequency intervals by configuring the circuit parameters of the timing logic circuit 06A, generally if the first predetermined frequency is located at [20kHz,50kHz ], for example 30kHz, the overall performance is better, for example, a higher strobe frequency is not easily perceived by the human eye, meanwhile, the generated electromagnetic interference is not too large. Here, the exemplary configurations of the timing logic circuit 06A in the pair of control units 05A described above may also be applied to any other related embodiments of the present invention.

The first predetermined frequency, which may be set by configuration of the circuit parameters of the timing logic circuit 06A, is substantially equal in value to the frequency of the alternating/rotational conduction of the plurality of switching cells and the corresponding plurality of bypass loops or plurality of portions of the LED array controlled by the timing logic circuit 06A. When the first predetermined frequency is set to be high, human eyes cannot easily or cannot sense, for example, stroboflash larger than 3125HZ can be considered safe so as to exempt from review of strobe depth, alternation/rotation larger than audio frequency (about 20KHZ) can avoid generating noise which is heard by human ears and is caused by energy change, alternation/rotation larger than 40K can avoid interference on infrared equipment and the like, however, the frequency is high, the energy change generated by alternation/rotation conduction can cause more electromagnetic interference, and more precise design is required; in addition, since it is not easy to implement a large capacitance in the integrated circuit process, the first predetermined frequency needs to be set in consideration of various factors. Generally speaking, if the first predetermined frequency is set at [4kHz,30kHz ], [50kHz,100kHz ], the overall performance is better, and the strobe frequency, the electromagnetic interference intensity, the manufacturability of the integrated circuit and other factors are considered. Here, the exemplary configurations of the timing logic circuit 06A in the pair of control units 05A described above may also be applied to any other related embodiments of the present invention.

Optionally, during the fluctuation of the first electrical signal with respect to the first threshold value, the current in the current limiting device Q0 and the currents in the plurality of switching cells being switched are coordinated such that the sum of the powers of the two LED arrays is kept substantially constant, e.g. always within the neighborhood of the first power value, in a state where the plurality of switching cells are all off and at least one on.

Alternatively, the rotation process between the first to the second bypass loops may be to switch to the first bypass loop for a time corresponding to the first time signal in response to the first electrical signal being lower than the first threshold, then switch to the second bypass loop for a time corresponding to the second time signal, switch to the first bypass loop for a time corresponding to the first time signal, and thus turn on the first bypass loop and the second bypass loop.

As shown in fig. 19B, there is provided a control circuit 01, a drive circuit 08B, wherein m is 2 and x is 1, the control circuit 01 including a floating-ground switching unit SW21, a common-ground switching unit I21, a current limiting device I22, and a control unit 05; the cathode of the common ground switch unit I21, the cathode of the current limiting device I22 and the cathode of the direct current power supply V21 are connected; the cathode of the floating switch unit SW21 is connected with the anode of the common ground switch unit I21, and the anode of the common ground switch unit I21, the anode of the current limiting device I22 and the anode of the floating switch unit SW21 are connected with the first LED array D21 and the second LED array D22.

The control unit 05 comprises an electrical signal measuring unit 02 and a timing logic circuit 06; the input end of the electrical signal measuring unit 02 is coupled to the anode of the current limiting device I22 to obtain a first electrical signal related to the dc voltage V21 (or, the difference between the dc voltage V21 and the total conduction voltage drop of the two LED arrays D21, D22), the electrical signal measuring unit 02 further includes a comparator and configures a first threshold, and the first electrical signal and the first threshold are compared by the comparator to generate a comparison signal reflecting the magnitude relationship between the first electrical signal and the first threshold, where the comparator may also adopt an amplifier or other circuit or device capable of reflecting the magnitude relationship of the signal. The input end of the timing logic circuit 06 is connected with the output end of the electric signal measuring unit 02, the output end is connected with the control end of the floating switch unit SW21 and the control end of the current limiting device I22, and the control end of the common ground switch unit I21 is connected with the comparison signal.

The timing logic circuit 06 includes a timer 03 and a flip-flop 04; the electric signal measuring unit 02, the timer 03 and the trigger 04 are sequentially connected, and the output end of the trigger 04 is connected with the control end of the floating switch unit SW 21; the timer 03 responds to the comparison signal to reflect that the voltage of the dc voltage V21 is in the first voltage interval, and generates two timing signals, and the flip-flop 04 generates two alternate time signals corresponding to the first predetermined frequency according to the two timing signals, and the two time signals are preferably complementary in the time domain, so as to control the two bypass loops to be alternately turned on at the time corresponding to the two time signals respectively.

Optionally, the current of the current limiting device I22 is controlled by the timing logic circuit 06 and the current of the common ground switch I21 is controlled by the comparison signal, so that the currents of the two bypass loops are greater than the current of the main loop when the voltage of the dc voltage V21 is in the first voltage interval.

Fig. 20 shows a partial operation waveform of the driving circuit 08A (or the driving circuit 08B), and for convenience of understanding, assuming that the conduction voltage drop of the LED array is approximately constant, the sum of the conduction voltage drop of the first LED array D21 being VD21, the conduction voltage drop of the second LED array D22 being VD22, and the conduction voltage drop of the first LED array D21 and the second LED array D22 being VD21+ VD 22.

Wherein, the horizontal axis is a time axis and is divided into two time intervals: before time T001 and after time T001.

Before time T001, the voltage V21(T) of the dc power supply V21 is greater than VD21+ VD22, as shown by the vertical axis in fig. 20, the floating switch unit SW21 is turned OFF, the current of the common switch unit I21 is turned OFF to zero corresponding to the OFF state in fig. 20, the current limiting device I22 is turned on corresponding to the I21(T) waveform in fig. 20, the current is IL, the currents of the first LED array D21 and the second LED array D22 are both IL corresponding to the I22(T) waveform in fig. 20, and the currents of the first LED array D21 and the second LED array D22 are both IL corresponding to the ID21(T) and ID22(T) waveforms in fig. 20.

After time T001, the voltage V21(T) of the dc power supply V21 is smaller than VD21+ VD22 and larger than the larger of VD21 and VD22, as shown by the vertical axis in fig. 20, at this time, the floating switch unit SW21 and the common ground switch unit I21 are alternately switched between the first state and the second state, in the first state, the floating switch unit SW21 is turned off, the common ground switch unit I21 is turned on by IH1, the current of the current limiting device is zero, the current of the first LED array D21 is IH1, and the current of the second LED array D22 is zero; in the second state, the floating switch unit SW21 is turned on, the common ground switch unit is turned off, the current limiting device is turned on by IH2, the current of the first LED array D21 is zero, and the current of the second LED array D22 is IH 2.

The turn-on voltage drops of the first LED array D21 and the second LED array D22 may be the same or different, and accordingly, after the time T001, the current IH1 of the common ground switch unit and the current IH2 of the current limiting device may also be the same or different, and in order to maintain the power of the LED arrays as constant as possible, the configuration is optimized such that the product of VD21 and IH1 is equal to the product of VD22 and IH2, and if the LED arrays are LEDs, the variation of the light emission amount and the stroboflash can be reduced.

If the conduction voltage drops of first LED array D21 and second LED array D22 are configured the same, the more common applications are in a 24V or 12V battery powered environment and an AC approximately 110VAC or approximately 220VAC powered environment, which may be used to generate a power supply by rectifying and filtering AC power.

Another common application is a single input voltage, such as 220VAC power environment, where a third LED array D23 can be connected in series with the power supply output in order to achieve a wide power supply voltage range and good conversion efficiency over a wide fluctuation range, as shown in fig. 21. In fig. 21, a dc power supply 07 is supplied with an AC power AC001 through a rectifier DB001, and both output terminals of the rectifier DB001 are connected in parallel to a filter capacitor C001 to smooth a supply power voltage.

In fig. 21, the third LED array D23 is connected in series to a closed loop formed by the dc power supply 07, the first LED array D21, the second LED array D22 and the current limiting device I22, one end of the third LED array D23 is connected to the output terminal of the dc power supply 07, and fig. 21 shows that the third LED array D23 is connected to the positive output terminal of the dc power supply 07, but in practical application, it may be connected to the negative output terminal of the dc power supply 07, or the third LED array D23 is divided into two parts, one part is connected to the positive output terminal of the dc power supply 07, and the other part is connected to the negative output terminal of the dc power supply 07. The better conversion efficiency obtained after connecting the third LED array D23 in series as shown in fig. 21 is illustrated as follows:

in the absence of the third LED array D23, the efficiency rate of the first energy loop is approximately the conduction voltage drop of the first LED array D21 divided by the voltage of the dc power supply 07; the efficiency value of the second energy loop is about the conduction voltage drop of the second LED array D22 divided by the voltage of the dc power supply 07; the efficiency of the third energy circuit is about the sum of the conduction voltage drops of the first LED array D21 and the second LED array D22 divided by the voltage of the dc power supply 07. it is expected that the efficiency of the energy conversion of the first energy circuit and/or the second energy circuit will be smaller when the voltage of the dc power supply 07 is just insufficient to drive the third energy circuit and the driving circuit 08A is switched to the first energy circuit and/or the second energy circuit. Examples are as follows: the sum of the conduction voltage drops of the first LED array D21 and the second LED array D22 is 250V, the voltage variation range of the dc power supply 07 is 240V-260V, and it can be calculated that the efficiency of the third energy loop is higher and is not less than 250/260 ≈ 96% (assuming that the voltage of the dc power supply 07 is 260V), but the efficiency of the first energy loop and the second energy loop is difficult to optimize, and the efficiency value of one of the first energy loop and the second energy loop does not exceed (250/2)/240 ≈ 52% (assuming that the voltage of the dc power supply 07 is 240V) no matter how the conduction voltage drops of the first LED array D21 and the second LED array D22 are distributed.

If the third LED array D23 is available, the energy conversion efficiency of the first energy loop is the sum of the conduction voltage drops of the first LED array D21 and the third LED array D23 divided by the voltage of the DC power supply 07; the energy conversion efficiency of the second energy loop is the sum of the conduction voltage drops of the second LED array D22 and the third LED array D23 divided by the voltage of the DC power supply 07; the efficiency of energy conversion of the third energy loop is the sum of the conduction voltage drops of the first LED array D21, the second LED array D22 and the third LED array D23 divided by the voltage of the dc power supply 07, and when the voltage of the dc power supply 07 is just insufficient to drive the third energy loop, and the driving circuit 08A is switched to the first and/or second energy loop, the efficiency of energy conversion is improved, for example, as follows: the sum of the conduction voltage drops of the first LED array D21, the second LED array D22 and the third LED array D23 is 250V, the voltage variation range of the dc power supply 07 is 240V to 260V, and the efficiency of the third energy loop is high: not less than 250/260 ≈ 96% (assuming that the voltage of the dc power supply 07 is 260V), but the efficiency of the first energy loop and the second energy loop may be optimized, for example, assuming that the turn-on voltage drop of the third LED array D23 is set to 200V and the turn-on voltage drops of the first LED array D21 and the second LED array D22 are both set to 25V, the efficiency values of the first energy loop and the second energy loop are 225/240 ≈ 94% at the maximum (assuming that the voltage of the dc power supply 07 is 240V).

In fig. 21, different energy circuits are formed according to the states of the floating switch unit SW21 and the common ground switch unit I21, which are respectively:

I) when the voltage of the direct current power supply V21 is greater than the sum of the turn-on voltage drops of the third LED array D23, the first LED array D21 and the second LED array D22, the floating switch unit SW21 and the common ground switch unit I21 are all turned off, forming a third energy loop: the dc power source V21 → the third LED array D23 → the first LED array D21 → the second LED array D22 → the current limiting device I22 → the dc power source V21, which powers the third LED array D23, the first LED array D21 and the second LED array D22.

II) when the voltage of the dc power source V21 is less than the sum of the turn-on voltage drops of the third LED array D23, the first LED array D21 and the second LED array D22, and is greater than the sum of the turn-on voltage drops of the third LED array D23 and the first LED array D21, and is also greater than the sum of the turn-on voltage drops of the third LED array D23 and the second LED array D22, controlling the floating switch unit SW21 and the common ground switch unit I21 to alternately switch between a first state and a second state, the first state being that the floating switch unit SW21 is turned off, and the common ground switch unit I21 is turned on, so as to form a first energy loop: the direct current power supply V21 → the third LED array D23 → the first LED array D21 → the common ground switching unit I21 → the direct current power supply V21, which supplies power to the third LED array D23 and the first LED array D21; the second state is that the floating switch unit SW21 is turned on, the common ground switch unit I21 is turned off, and a second energy loop is formed: the dc power supply V21 → the third LED array D23 → the floating ground switch unit SW21 → the second LED array D22 → the current limiting device I22 → the dc power supply V21, which supplies power to the third LED array D23 and the second LED array D22.

III) when the voltage of the dc power V21 is less than the sum of the conduction voltage drops of the third LED array D23 and the first LED array D21, and is less than the sum of the conduction voltage drops of the third LED array D23 and the second LED array D22, controlling both the floating switch unit SW22 and the common ground switch unit I21 to be turned on, so as to form a fourth energy loop: the dc power supply V21 → the third LED array D23 → the floating switch unit SW22 → the common ground switch unit I21 → the dc power supply V21, which supplies power to the third LED array D23.

The beneficial effects are as follows: when the LED lamp runs in the first energy loop, the second energy loop and the third energy loop, all the LED arrays can be lightened, the currents of the first energy loop and the second energy loop are properly configured to be larger than the current of the third energy loop, approximately constant LED array power and luminous brightness can be obtained, the wider power supply voltage range, the better conversion efficiency and the better luminous stability are considered, and the luminous stroboflash of the LED is reduced; when the light source operates in the fourth energy loop, only the third LED array is turned on, or the current of the fourth energy loop is set to be larger than the current of the first energy loop and/or the current of the second energy loop and/or the current of the third energy loop, so that an improved light emitting effect is obtained and stroboflash is considered, and the specific setting mode is not repeated.

Fig. 22 shows a more optimized partial operation waveform corresponding to fig. 21, in which the horizontal axis is a time axis, and V21(T) on the vertical axis corresponds to a voltage waveform of the power supply source, which is a voltage having a pulsating cycle; for convenience of understanding, assuming that the conduction voltage drops of the LED arrays are constant, the conduction voltage drops of the first LED array D21, D22 and D23 are VD21, VD22 and VD23, and VD2 is equal to VD3, the sum of the conduction voltage drops of the first LED array D21, the second LED array D22 and the third LED array D23 is VD21+ VD22+ VD23, the sum of the conduction voltage drops of the third LED array D23 and the first LED array D21 is VD23+ VD21, the sum of the conduction voltage drops of the third LED array D23 and the second LED array D22 is VD23+ VD22, and the time intervals and the action waveforms are different according to the correspondence relationship between the power supply voltage and the conduction voltage drops of the LED arrays:

in fig. 22, in a time interval from T2 to T3, the voltage V21(T) of the dc power supply V21 is greater than VD21+ VD22+ VD23, the floating switch unit SW21 is turned OFF, the current of the common switch unit I21 is turned OFF to zero corresponding to the OFF state of SW22 in fig. 22, the current limiting device I22 is turned on corresponding to the I21(T) waveform in fig. 22, and the current is IL corresponding to the I22(T) waveform in fig. 22, and the currents of the first LED array D21, the second LED array D22, and the LED array D23 are all IL corresponding to the waveforms of ID21(T), ID22(T), and ID23(T) in fig. 22.

In fig. 22, in the time interval T1-T2 and the time interval T3-T4, the voltage V21(T) of the dc power supply V21 is less than VD21+ VD22+ VD23 and greater than VD23+ VD22 and VD23+ VD21, at this time, the floating switch unit SW21 and the common ground switch unit I21 are alternately switched between the first state and the second state, in the first state, the floating switch unit SW21 is turned off, the common ground switch unit I21 is turned on by IM, the current of the current limiting device is zero, the currents of the first LED array D21 and the LED array D23 are IM, and the current of the second LED array D22 is zero; in the second state, the floating switch unit SW21 is turned on, the common ground switch unit is turned off, the current limiting device is turned on by IM, the current of the first LED array D21 is zero, and the currents of the second LED array D22 and the LED array D23 are IM.

In fig. 22, in the time interval T0-T1 and the time interval T4-T5, the voltage V21(T) of the dc power supply V21 is less than VD23+ VD22 and VD23+ VD21 and greater than VD23, at this time, the floating switch unit SW21 is turned on, the common ground switch unit is turned on by IH, the current of the current limiting device is zero, the currents of the first LED array D21 and the second LED array D22 are zero, and the current of the LED array D23 is IH.

In fig. 22, T1 ', T2 ', T3 ', T4 ' and T5 ' are the times in the next ripple cycle of the power supply voltage, and correspond to T1, T2, T3, T4 and T5, respectively, and the above process is repeated in the corresponding time interval.

In fig. 22, the switching frequency of the first state and the second state is higher than the ripple frequency of the rectified output voltage in two time intervals T1-T2 and T3-T4, which respectively include several first states and second states, and both of which start from the first state, which is only an example and not a limitation, and in the specific implementation, it can be set to start from the second state, or one time interval starts from the first state and another time interval starts from the second state, and when the switching frequency is much higher than the ripple frequency, the first LED array D21 and the second LED array D22 have almost the same power in two time intervals T1-T2 and T3-T4.

In fig. 22, appropriate values of IL, IM, and IH are configured according to the LED arrays turned on corresponding to the time intervals, so that when the power supply voltage fluctuates periodically, the total power of the LED arrays is approximately constant, and the variation of the light emission amount and the stroboscopic light can be reduced; in addition, since it is assumed in fig. 22 that the turn-on voltage drops of the first LED array D21 and the second LED array D22 are the same, the current values IM corresponding to the common ground switching unit I21 and the current limiting device I22 are also the same, otherwise, the respective values need to be set separately to obtain that the total power of the LED arrays is approximately constant; moreover, in the time interval T0-T1 and the time interval T4-T1', the common ground switch unit I21 corresponds to a larger current value IH, however, this is not necessary in practical applications, for example, low-priced goods require simpler design, and the requirement for the value of IH, for example, IH is designed to IM, can be reduced.

In fig. 22, the fluctuation of the power supply voltage in one pulse cycle is large, and is to illustrate the operation waveforms of the power supply voltage and the LED array conduction voltage drop in different corresponding relationships, respectively, in practical applications, due to the difference between the power supply voltage and the LED array conduction voltage drop corresponding relationships, the operation waveforms corresponding to the above time intervals may only partially occur, for example, when the power supply voltage is stable, the operation waveforms of the time interval T0-T1 and the time interval T4-T1' do not occur, and thus, the time interval does not need to be considered when designing the actual commercial product.

In more detail, the switching manner between the first state and the second state in two time intervals T1-T2 and T3-T4 as shown in fig. 22 is not unique, and may further include:

1) alternately switching two time intervals in one pulsation cycle, as shown in fig. 23, setting a time interval T1-T2 and a time interval T1 '-T2' as a first state, and setting a time interval T3-T4 and a time interval T3 '-T4' as a second state; alternatively, as shown in FIG. 24, the time intervals T1-T2 and T1 '-T2' are set as the second state, and the time intervals T3-T4 and T3 '-T4' are set as the first state; in this switching manner, the conduction time of the first LED array D21 and the conduction time of the second LED array D22 are different between the two time intervals T1-T2 and T3-T4, and accordingly, the current and the power are not easily the same, but the switching higher than the ripple frequency shown in fig. 22 is not required, so that the control unit is simple and has practical value.

2) Alternately switching in two adjacent pulsing periods: as shown in fig. 25, the time intervals T1-T2 and T3-T4 in the first pulsation cycle are set as the first state, and the time intervals T1 '-T2' and T3 '-T4' in the second pulsation cycle are set as the second state; or conversely, as shown in FIG. 26, the time interval T1-T2 and the time interval T3-T4 in the first pulse cycle are set as the second state, and the time interval T1 '-T2' and the time interval T3 '-T4' in the second pulse cycle are set as the first state; this approach also achieves approximately constant total power of the LED arrays due to the approximation of the supply voltage waveform of two adjacent ripple cycles, which has the disadvantage that the alternating lighting of the first and second LED arrays D21, D22 at a lower ripple frequency than the rectified grid may have an effect on the lighting comfort, but the circuit is simple and of practical value.

In summary of fig. 22, 23, 24, 25 and 26, in the time interval T1-T2, the time interval T3-T4, the time interval T1 '-T2' and the time interval T3 '-T4', the floating switch unit and the common switch unit alternately operate in the first state and the second state, i) the first state and the second state may be switched a plurality of times in one time interval, ii) the first state and the second state may be alternately switched in two time intervals within one pulse cycle, iii) the first state and the second state may be alternately switched in two adjacent pulse cycles, or a combination of the above-mentioned i), ii) and iii).

The foregoing embodiment can achieve approximately constant light emission amount by changing the total power of the current-controlled LED array approximately constant when the power supply voltage changes, which has a positive effect on reducing the light emission strobe of the LEDs, however, due to the periodic change of the dc power supply 07 (or power supply) voltage, the driving circuit may periodically turn on different loops and LED arrays located on different loops, correspondingly, the current/light emission amount of each LED changes periodically, and extremely, when the human eye or the testing instrument is at an infinite distance from the LEDs, the light emission strobe of a single LED can be sensed; when human eyes or a test instrument are infinitely far away from the LED, because the perceived light-emitting quantity is the total light-emitting quantity of all the LEDs, the stroboflash cannot be perceived, namely no stroboflash exists; the practical situation is that human eyes or test instruments cannot be used or tested at an infinite distance or at an infinite distance, and the optical processing part of the lighting device and the influence of air on light rays and the like have a certain reduction effect on stroboflash, and one kind of experimental data is as follows: the test instrument can test the strobe depth to about 3-5% beyond a few centimeters or a dozen centimeters from the LED, or can photograph slight ripples when a camera is used to photograph within a dozen centimeters.

It should be noted that, in this embodiment, the LED array is taken as an example for description, and in other embodiments, the control circuit and the driving circuit provided in this embodiment may also be applied to control and drive other light emitting loads, such as an OLED or other solid state light emitting devices.

The present embodiment also provides a lighting device having at least one of the driving circuits shown in some of the above embodiments.

Example sixteen

Also proposed in this embodiment is a lighting device, as shown in fig. 28, 29, 30 and 37, including a driving circuit in other embodiments of the present application, and a first load and a second load. For example, the second load may be an LED array in the second bypass loop in some other embodiments, or an LED array in the second portion of LED arrays; the first load may be an array of LEDs in the first bypass loop in some other embodiments, or an array of LEDs in the first portion of an array of LEDs. The first part of the LED array and the second part of the LED array have different stroboscopic characteristics due to different loops. The first load and the second load are each configured as a lighting load and each comprise one LED or a plurality of LEDs, wherein the plurality of LEDs may be connected in series and/or in parallel.

Fig. 37 is a schematic diagram of a layout of two-part LEDs with different stroboscopic characteristics in n LED arrays according to another embodiment of the present invention. As shown, the second partial LED array Sparkling _ z1 and the first partial LED array Const _ z1 of the two-partial LED array are arranged to overlap to some extent. In other words, the second partial LED array Sparkling _ z1 is partially dispersed/enclosed in the first partial LED array Const _ z1, as shown, the outer contour region (outer contour) out line _ z1 of the second partial LED array Sparkling _ z1 and the outer contour region out line _ z2 of the first partial LED array Const _ z1 also Overlap in a certain proportion, for example, the overlapping region overlay _ z1 may occupy about 60% of the outer contour region out line _ z1 in area. Thus, at least within or around the overlap region overlap _ z1, the strobes in the light radiated (illuminating) by the second partial LED array Sparkling _ z1 with higher strobes are masked to some extent by the first partial LED array Const _ z1 with lower or no strobes, thereby reducing the strobes of the driving circuit or the lighting device as a whole.

In fig. 28, a substrate OUTLINE-PCB is included, configured to carry a first portion LED array LED 21-1, D21-2.. D21-20, and a second portion LED array LED D22-1, D22-2, D22-3, and D22-4, the first portion LED array LED 21-1, D21-2.. D21-20 forming an OUTLINE region OUTLINE-D21, the second portion LED array LED D22-1, D22-2, D22-3, and D22-4 forming an OUTLINE region OUTLINE-D22, the plurality of LEDs in the second portion LED array and the plurality of LEDs in the first portion LED array being arranged in a rectangle.

In fig. 29, a substrate OUTLINE-PCB ' is included that is configured to carry a first portion LED array LED 21-1 ', D21-2 '... D21-6 ', and second portion LED arrays LED D22-1 ', D22-2 ', D22-3 ' and D22-4 ', the first portion LED arrays LED 21-1 ', D21-2 '... D21-6 ' forming an OUTLINE region OUTLINE-D21 ', the second portion LED arrays LED D22-1 ', D22-2 ', D22-3 ' and D22-4 ' forming an OUTLINE region oute-D22 ', the plurality of LEDs in the second portion LED arrays are arranged substantially in a rectangular shape, and the plurality of LEDs in the first portion LED arrays are arranged substantially in a circular ring shape.

In fig. 30, a substrate OUTLINE-PCB "is included, configured to carry a first portion of LED arrays LEDD 21-1", D21-2 ". multidot.. D21-6", and a second portion of LED arrays D22-1 ", D22-2", and D22-3 ", the first portion of LED arrays LEDD 21-1", D21-2 ". multidot.. D21-6" forming an OUTLINE region OUTLINE-D21 ", the second portion of LED arrays LEDD 22-1", D22-2 ", and D22-3" forming an OUTLINE region OUTLINE-D22 ", the plurality of LEDs in the second portion of LED arrays are arranged in a polygonal ring, and the plurality of LEDs in the first portion of LED arrays are arranged in a triangular ring.

Fig. 28, 29 and 30 have some or all of the following features, respectively:

the LEDs in the first part of LED arrays are arranged in a staggered mode with the LEDs in the second part of LED arrays, and the outline areas of the LEDs in the first part of LED arrays and the LEDs in the second part of LED arrays partially overlap;

the plurality of LEDs in the second part of LED array are distributed in the outline area of the plurality of LEDs in the first part of LED array;

the plurality of LEDs in the second part of LED array are distributed and surrounded by the plurality of LEDs in the first part of LED array.

The second part of the LED array is distributed in the outline area of the plurality of LEDs in the first part of the LED array;

the outline areas of the plurality of LEDs in the second part of LED array and the outline areas of the plurality of LEDs in the first part of LED array have 60% -100% overlap;

a plurality of LEDs in the second portion of LED arrays and a plurality of LEDs in the first portion of LED arrays are distributed substantially symmetrically about a center of the overall outline area in the first portion of LED arrays and the second portion of LED arrays;

the LEDs in the second part of LED arrays and the LEDs in the first part of LED arrays are respectively arranged in a central symmetry mode; and the center of symmetry of one or more LEDs in the second partial LED array is substantially coincident with the center of symmetry of the plurality of LEDs in the first partial LED array;

One LED in the second part of LED array is substantially disposed at the symmetric center of the plurality of LEDs in the first part of LED array, or the plurality of LEDs in the second part of LED array and/or the plurality of LEDs in the first part of LED array are arranged in a rectangular, circular, or annular shape, which may, of course, also include a curved/linear, symmetric or asymmetric radial shape, and will not be described again;

the plurality of LEDs in the first partial LED array are distributed in a rectangular, circular, annular area on the substrate, or obviously, in a curved/linear, symmetrical or asymmetrical radial area, and one or more LEDs in the second partial LED array are distributed in the plurality of LEDs in the first partial LED array;

one or more LEDs in the second part of LED array are distributed in a rectangular shape, a circular shape, a ring shape, a curved/linear shape which can be deformed, a symmetrical or asymmetrical radial shape; and, the one or more LED outline regions in the second part of the LED array are comparable in area to, or at least 10% smaller in proportion to, the outline regions of the plurality of LEDs in the first part of the LED array.

Further, it is conceivable that one or more LEDs of the second partial LED array and one or more LEDs of the first partial LED array are adjacently arranged correspondingly or in pairs.

Since the first and second loads D21 and D22 each include one or more LED lighting units, the plurality of LED lighting units may distributively/dispersively carry and discharge power of the first or second load D21 or D22 in the form of light energy. The LED light emitting units of the first and second loads D21 and D22 may be at least partially staggered, for example, the first and second loads D21 and D22 may have overlapping outline regions, or have overlapping outlines/envelopes as a whole. Since there is an overlap between the outline regions formed by the first load D21 and the second load D22, although only the first load D21 is turned on and the second load D22 is turned off when the voltage ratio of the dc power supply is low, and thus there may be some stroboflash/flicker, since the first load D21 in the overlap region is still in a normally on state under a normal low voltage condition, the second load D22 is temporarily turned off and can be compensated by the light emitted from the normally on first load D21. This reduces or masks the stroboscopic effect of the second load D22 at low voltage to some extent. Moreover, in general, the larger the overlapping area of the second load D22 and the first load D21, that is, the more the two overlapping outline areas coincide, the more the first load D21 can hide the concealment of the low-voltage strobe of the second load D22 with its high tolerance for the low voltage.

Further, the staggered arrangement regions of the first and second loads D21 and D22 may be more overlapped, so that the region that is substantially normally bright and has low stroboflash is larger. Therefore, further, the second load D22 may be disposed entirely within the first load D21, that is, the outline area of the second load D22 is located entirely within the outline area of the first load D21, as shown in the figure.

Optionally, the plurality of LEDs 21 in the first load D21 has a first number, and the plurality of LEDs 22 in the second load D22 has a second number, the first number being greater than the second number, in which case the first load D21 has a dominant number, the strobe masking for the second load D22 is better in some LED layout modes.

Optionally, the plurality of LEDs in the second load D22 and the plurality of LEDs of the first load D21 are substantially symmetrically distributed around the center of the overall outline area of the first load and the second load. Alternatively, the center of symmetry of the plurality of LEDs of the first load D21 is set as the center of symmetry when the second load D22 is disposed. And if only one LED of the second load D22 is included, it may be disposed substantially at the center of symmetry of the plurality of LEDs of the first load D21. The second load D22 and the first load D21 are arranged in a centrosymmetric manner, which can be seen in the figure

Alternatively, the layout shape of the centrosymmetric LED may include: rectangular, circular, annular, curved/rectilinear, symmetrical or asymmetrical radial, etc.

The plurality of LEDs 21 and the plurality of LEDs 22 are arranged in a ring around the circuit substrate, e.g., in a radially corresponding arrangement or in a radially staggered arrangement. Therefore, locally, the pair of the LED21 and the LED22 (pair) disposed adjacently can achieve complementation of the lit and extinguished states, so that the pair of the LED21 and the LED22 can be kept substantially constantly lit at the position on the substrate and the peripheral region thereof.

Further, the plurality of LEDs 21 and the plurality of LEDs 22 may be arranged on the circuit substrate in a somewhat uniform manner, such as "carpet" or distributed circumferentially in a circle, square, or regular hexagon, distributed over the circuit substrate. For example, 10 LEDs 21 are arranged in an outer ring with a slightly larger radius, while 10 LEDs 22 are arranged in a one-to-one correspondence in an inner ring with a slightly smaller radius. The arrangement of the plurality of LEDs 21 and the plurality of LEDs 22 evenly dispersed with each other can reduce stroboscopic effects.

Example seventeen

It can be known from the foregoing embodiments that, in the driving circuit, the current values of the main loop and each bypass loop are configured, and in response to the driving circuit operating in the corresponding main loop/bypass loop, the sum of the powers of the LED arrays on the different turned-on main loop/bypass loops is located in the neighborhood of the first power value, so that the luminous flux can be substantially maintained unchanged, thereby reducing the stroboflash or improving the light emission fluctuation of the LED arrays from the frequency perspective.

When the dc power supply is a battery or a switching power supply, the output voltage waveform is substantially flat, so that normally, the driving circuit continuously operates in the main loop, a bypass loop or a combination of bypass loops (including at least two bypass loops alternately/alternately conducting at a first predetermined frequency), and can be considered to be no strobe or be a safe ripple frequency to avoid the review of strobe depth.

When the dc power supply is generated by rectifying and smoothing ac power, the output voltage waveform is pulsating, the ac power frequency is usually 50/60HZ, and the rectified pulsating frequency is 100/120HZ, and there are cases where: in different time intervals in a pulse cycle, corresponding pulse direct-current voltages are different, the driving circuits respectively operate in different loops, and the loops comprise: in the main circuit, the bypass circuit, or the combination of the bypass circuits, the light emission amounts of the LED arrays located in different circuits are different in response to the different circuits in operation, and/or the sum of the light emission amounts of all the LED arrays in different circuits is different or slightly different, and thus further improvement is desired.

Further, the present embodiment provides an inventive concept: under a fixed alternating voltage or a fixed pulsating direct voltage, the control unit controls the driving circuit to continuously operate in the main loop, a fixed bypass loop or a fixed combination of bypass loops according to whether the pulsating direct voltage is enough to drive n (or less than n) LED arrays in at least one pulsating period so as to reduce or eliminate low-frequency stroboflash generated when the driving circuit operates in different loops respectively in different time intervals in one pulsating period.

It should be noted that, the pulsating dc voltage is constantly and periodically changed, and the number of LED arrays that can be driven by the pulsating dc voltage depends on the number of LEDs that can be driven by the minimum occurring in the pulsating period, in this embodiment, whether the pulsating dc voltage is enough to drive n (or less than n) LED arrays may also be understood as: whether the minimum value of the pulsating direct current voltage is sufficient to support the turn-on voltage drop of n (or less than n) LED arrays, or whether the minimum value of the pulsating direct current voltage is sufficient to support n (or less than n) LED arrays having sufficient voltage/current/power to meet the required luminous flux when turned on simultaneously.

In this embodiment, the control unit includes an electrical signal measuring unit, and the electrical signal measuring unit includes:

a second electrical signal is configured that reflects or positively/negatively correlates with i) a minimum value of the pulsating dc voltage ii) a minimum value of a difference between the pulsating dc voltage and a voltage experienced by the LED array. The present specification takes the minimum value of the second electrical signal positively correlated to the pulsating dc voltage or the minimum value of the difference between the pulsating dc voltage and the voltage received by the LED array as an example.

Alternatively, the second electrical signal may be taken from the first electrical signal.

Alternatively, the second electrical signal may be taken from both ends of the dc power source, or, alternatively, through circuitry coupled to the positive and negative polarity outputs of the dc power source.

Alternatively, in a state where at least one switching unit is turned off, the second electric signal may be acquired based on one or more circuit parameters in the control circuit. For example, the second electrical signal may be taken from at least one of a voltage across the current limiting device, a voltage at a control terminal of the current limiting device, and a current of the current limiting device.

Alternatively, in a state where the at least one switching unit is turned on, the second electric signal is taken from at least one of a both-end voltage of the current limiting device, a control-end voltage of the current limiting device, and a current of the current limiting device.

Alternatively, the second electrical signal may be taken from both ends of at least one common ground switch.

The specific method comprises the following steps:

1) the power supply is coupled to two ends of the direct current power supply and used for collecting the output voltage of the direct current power supply; or,

2) coupled across a resistor or MOS transistor (e.g., a current limiting device) located on the main/bypass loop; or,

3) coupled to both ends of at least one LED array connected in series in the main loop.

Alternatively, a law of variation based on the pulsating dc voltage or the difference between the pulsating dc voltage and the voltage sustained by the LED array under a fixed implementation may be foreseen or calculated, i.e. a second electrical signal reflecting the minimum value of the pulsating dc voltage (or the minimum value of the first electrical signal) may be calculated or obtained by suitable circuit transformation from one or more of the periodic parameter characteristics of the pulsating dc voltage (or the difference between the pulsating dc voltage and the voltage sustained by the LED array), such as the maximum value, the minimum value, the average value, the effective value or other time-varying voltage laws. For example, the pulsating direct current voltage or the difference between the pulsating direct current voltage and the voltage received by the LED array periodically decreases to a minimum value (a valley value) and then starts to increase, a time corresponding to the pulsating direct current voltage being at the minimum value (the valley value) can be obtained by detecting the slope of the voltage change, and the pulsating direct current voltage is sampled at or near the time, so that the minimum value of the difference between the pulsating direct current voltage or the pulsating direct current voltage and the voltage received by the LED array in the pulsating cycle can be obtained. And, the second electrical signal reflecting the minimum value of the pulsating direct current voltage (or the difference between the pulsating direct current voltage and the voltage received by the LED array) can also be obtained by other means or methods. For simplicity, the details are not described.

Alternatively, in practical applications, after the mains voltage is reduced, it is desirable that the light emission of the LED array cannot be suddenly reduced or is suddenly reduced too much, so that, once the mains voltage is reduced, the driving circuit 100 needs to be timely switched to the bypass circuit corresponding to the pulsating dc voltage value to maintain sufficient LED array conduction and luminous flux to meet the demand. However, it is less important whether the driving circuit is switched to the bypass circuit or the main circuit corresponding to the pulsating dc voltage value in due time after the mains voltage is increased, because even if the driving circuit is not switched to the bypass circuit or the main circuit corresponding to the pulsating dc voltage value in due time, the light emission of the LED array does not fluctuate greatly. Therefore, it is desirable that the second electrical signal is capable of timely reflecting the instantaneous value of the pulsating dc voltage, and in this respect, the second electrical signal for reflecting the reduction of the utility power may be configured as the first electrical signal, or the second electrical signal should be configured to timely reflect the difference between the pulsating dc voltage or the pulsating dc voltage and the voltage received by the LED array when the utility power is reduced.

In this embodiment, the electrical signal measuring unit further comprises a second comparator configured to compare the second electrical signal with the first threshold to generate a second comparison signal indicative of whether the pulsating dc voltage is sufficient to drive the n (or less than n) LED arrays, and in particular, in response to the second electrical signal reflecting the instantaneous value of the pulsating dc voltage being less than the first threshold, the second comparison signal is indicative of a minimum value of the pulsating dc voltage being insufficient to drive the n (or less than n) LED arrays; in response to the second electrical signal reflecting the minimum value of the pulsating direct current voltage being greater than the first threshold, the second comparison signal is indicative that the pulsating direct current voltage is sufficient to drive n (or less than n) LED arrays during a full cycle.

Alternatively, the number of conducting LED arrays (or the conducting voltage drop of the conducting LED arrays) that are sufficient to drive the pulsating dc voltage may be multiple, such as n or n-1, as described above, and thus the first threshold value may be configured to be multiple values, or the second electrical signal may be configured to be multiple values, so that the result of comparing the first threshold value and the second electrical signal reflects whether the pulsating dc voltage is sufficient to drive different numbers of LED arrays, respectively.

As shown in fig. 40 and 41, a drive circuit 100 and a control circuit 200 are provided.

In this embodiment, the driving circuit 100 includes a control circuit 200, a dc power U generated by rectifying and filtering ac power, and three LED arrays, in this embodiment, the control circuit 200 includes a control unit 110, as shown in fig. 41, the control unit 110 includes an electrical signal measuring unit 111 and a signal processing unit 112, wherein an input end of the electrical signal measuring unit 111 is coupled to the driving circuit 100 to obtain a second electrical signal,

the control unit 200 is configured to control the three switching units to bypass at least one LED array to keep the LED array that is not bypassed still conductive and to run at least one pulsating cycle of the dc power supply in response to the output voltage of the dc power supply U being insufficient to turn on the three LED arrays.

And an electrical signal measuring unit 111 configured to determine whether the output voltage of the dc power supply U is sufficient to turn on the three LED arrays.

And a signal processing unit 112 connected to the electrical signal measuring unit 111 and control terminals of the three switching units, respectively, and operable to control the switching units according to a comparison result of the electrical signal measuring unit 111.

Further, the electrical signal measuring unit 111 has a second comparator 113, one input terminal of the second comparator 113 is configured as a first threshold, the other input terminal is configured to receive a second electrical signal, an output terminal of the second comparator 113 is connected to the input terminal of the signal processing unit 112, the second comparator 113 compares the second electrical signal with the first threshold to determine whether the output voltage of the dc power U is sufficient to drive the three LED arrays, and sends a second comparison signal to the signal processing unit 112 according to the determination result, the signal processing unit 112 controls the control terminal of each switching unit connected to the output terminal thereof according to the second comparison signal to control the driving circuit 100 to continuously operate in the main loop, the fixed one bypass loop or the fixed one bypass loop combination in at least one pulse cycle.

Specifically, when the second electrical signal is greater than the first threshold, that is, the output voltage of the dc power supply U is sufficient to drive the three LED arrays, the driving circuit 100 continuously operates in the main loop for at least one pulse period; conversely, when the second electrical signal is smaller than the first threshold, that is, the output voltage of the dc power source U is not sufficient to drive the three LED arrays, the driving circuit 100 continuously operates in one or a combination of the first to sixth bypass loops for at least one pulse period.

The signal processing unit 112 is responsive to the second comparison signal to control the switching unit/current limiting device to operate in an on, off or regulated current mode, so that the driving circuit 100 operates in different loop modes, which may be designed according to different requirements. For example, when the output terminal drives the switch unit that is alternatively/alternately turned on, the timing logic circuit shown in the fifteenth embodiment needs to be designed, and otherwise, the timing logic circuit does not need to be designed; or, when the output end drives the floating switch unit, a level conversion circuit is needed to be included so that the second comparison signal can drive the floating switch unit in a matching way, otherwise, the level conversion circuit is not needed; or, the second comparison signal is processed in time sequence, for example, a rising edge/a falling edge of the second comparison signal is converted into a corresponding level signal, for example, a flip-flop with a set-reset function is used for conversion, or, similar to the flip-flop shown in the fifteenth embodiment of the present invention, even when m is 1 and x is 0 and there is only one common ground switching unit, the second comparison signal may directly drive the common ground switching unit, or only the signal processing unit 112 performs signal matching/buffering on the second comparison signal, and the like.

However, the mains voltage is connected to a plurality of loads, and the characteristics and operation of the plurality of loads are different, which may cause fluctuations in the mains voltage, such as a low effective value of the mains voltage during peak periods and a high effective value of the mains voltage during valley periods. In order to obtain better energy conversion efficiency and better maintain stable light emission of the LED array, the driving circuit 100 should be switched to different loops according to different mains voltages and continuously operate. Concomitantly, at the moment when the driving circuit 100 is controlled to switch from one loop (current loop) to another loop (target loop), the light emission amount of a single LED array or the total light emission amount of all the LED arrays may suddenly change, thereby causing a visually instantaneous sudden brightness change perceivable to human eyes, and in order to avoid the sudden brightness change, in the present embodiment, the switching of the driving circuit 100 in response to the mains voltage fluctuation is implemented in a manner of "gradual switching".

Optionally, the control unit 110 is configured to, in response to the valley voltage/partial voltage in a single pulse cycle being insufficient to switch on the three LED arrays, gradually complete the transition from switching on the three LED arrays to switching on a partial LED array (e.g. two LED arrays) by a subsequent plurality of pulse cycles. As shown in fig. 42A, the control unit 110 further includes an integrating unit 114, the integrating unit 114 is operable to output an integrated signal varying with time according to a determination result of whether the output voltage of the dc power U is sufficient to turn on the three LED arrays, specifically, an input terminal of the integrating unit 114 is connected to an output terminal of the second comparator 113, the integrating unit 114 controls an output terminal thereof to output the integrated signal varying with time in response to the second comparison signal, the integrated signal is input to an input terminal of the signal processing unit 112, and the switching unit/current limiting device is controlled by the output terminal of the signal processing unit to operate in a conducting, a blocking or a current adjusting mode, so that the driving circuit 100 operates in different loop modes. The driving circuit 100 is configured to gradually decrease the current running in the current loop and gradually increase the current running in the target loop in response to the change of the integral signal, and the driving circuit 100 runs in the gradual change transition direction from the current loop to the target loop; or, conversely, the direction of gradual change is reversed, so that the current running in the current loop is gradually increased, and the current running in the target loop is gradually reduced.

Optionally, as shown in fig. 42B, optionally, the electrical signal measuring unit 111 further includes a first comparator 116, one input terminal of the first comparator 116 is configured to collect the first electrical signal, the other input terminal is configured to integrate the signal, the output terminal of the first comparator 116 is connected to the input terminal of the signal processing unit 112, and the signal processing unit 112 controls the switching unit/current limiting device to operate in an on, off or adjusting current mode in response to the output of the first comparator 116, so that the driving circuit 100 operates in different loop modes. Optionally, the driving circuit 100 is configured to gradually decrease the ratio of the time of operating in the current loop and the time of operating in the target loop in response to a change in the integrated signal; or, conversely, the ratio of the time of operation on the current loop to the time of operation on the target loop is gradually increased.

Optionally, the integrating unit 114 includes an RC filter circuit (not shown) formed by at least a resistor and a capacitor, one end of the resistor is an input end of the integrating unit 114, the other end is an output end of the integrating unit 114, and two ends of the capacitor are respectively connected to the output end of the integrating unit 114 and the ground.

Optionally, the integrating unit 114 includes an up-down counter (not shown) and a digital-to-analog converter (not shown), an input end of the up-down counter is also the input end of the integrating unit 114, an output end of the up-down counter is connected to an input end of the digital-to-analog converter, an output end of the digital-to-analog converter is also the output end of the integrating unit, the up-down counter outputs an increasing or decreasing count signal at an output end of the up-down counter in response to a change of the second comparison signal, and the digital-to-analog converter outputs an integrating signal corresponding to the count signal.

Alternatively, the up-down counter may be an adder-subtractor.

Optionally, the up-down counter is responsive to the clock signal, the count signal being synchronized with the clock signal to increase or decrease cycle by cycle.

Preferably, the clock signal is synchronized to the period of the ripple or to the first predetermined frequency. Of course, the period/frequency of the clock signal may not be related to the period of the ripple or the first predetermined frequency.

Optionally, the signal processing unit 112 is configured to control the average value of the currents in the partial LED arrays (e.g. two LED arrays) and the average value of the currents in the three LED arrays to increase and decrease, respectively, according to the variation of the integrated signal over a plurality of pulsation periods.

Optionally, the signal processing unit 112 is further configured to: the relative proportion of the on-time that three LED arrays are fully on to the on-time that a portion of the LED arrays are individually on (e.g., two LED arrays) is coordinated to be sequentially decremented or incremented by a number of pulsing periods.

For easy understanding of the working principle, analogy can be made with the fifteenth embodiment, by the action of the output signal of the integrating unit in this embodiment, one input end of the first comparator can receive a variable quantity such as a ramp signal, which is equivalent to making the first threshold value as a constant quantity in the fifteenth embodiment variable with time, the first comparator 116 in this embodiment corresponds to the comparator in the fifteenth embodiment, the signal processing unit 112 in this embodiment corresponds to the timing logic circuit 06A in the fifteenth embodiment, and the output signal of the first electric signal and the integrated signal after being compared by the first comparator 116 in this embodiment corresponds to the comparison signal in the fifteenth embodiment. Based on the description of some embodiments, it can be understood by those skilled in the art that the present embodiment changes the time of the driving circuit 100 running in different loops or the ratio of the time of running in different loops through the variation of the integrated signal until the gradual transition process is completed.

It will be appreciated that the LED arrays emitting light at different time intervals in each pulse cycle of the ramp transition process are different, however, since the duration/duration of the ramp transition is short, after the ramp transition is completed or the ramp transition process is reversed/disengaged/exited, the driving circuit will remain operating in a fixed loop before the next ramp transition process begins, and at this time, the current conducted by the LED arrays in each pulse cycle is fixed or alternatively conducted at the first predetermined frequency, so that there is no low frequency stroboflash.

It should be noted that, during the gradual change transition, the smaller the variation amount of light per unit time, the less easily the human eye can perceive the sudden change of light, and therefore, it is desirable that the current of the current loop and the current of the target loop during the gradual change transition have the smallest possible variation amount per unit time, in other words, if the current of the current loop and the current of the target loop during the gradual change transition have constant or approximately constant variation amounts per unit time, the longer gradual change transition time is set to achieve that the current of the current loop and the current of the target loop have smaller variation amounts per unit time, for example, the gradual change transition time is set to be greater than 0.2 seconds.

In other words, the current of the target circuit and the current circuit are increased by the same amount or different amounts in the fixed interval (or the unfixed interval) synchronous or asynchronous with the pulse cycle, or the current of the target circuit and the current circuit are decreased by the same amount or different amounts in the fixed interval (or the unfixed interval) synchronous or asynchronous with the pulse cycle, so that the mutual gradual change conversion between different circuits can be realized, and one of the objectives is that the change amount of light in the control unit time is not easily sensed by human eyes in the gradual change conversion process. It still needs to be further explained that, in practical application scenarios, due to the fluctuation of the utility power, it may happen that: during a certain time period, the second electrical signal is smaller than the first threshold, the driving circuit 100 enters the ramp conversion process, however, during another time period, the second electrical signal is larger than the first threshold, in this case, the first mode, that is, the above-mentioned, may be adopted: adjusting the change direction of the integral signal in real time according to the fluctuation of the mains supply voltage, and adjusting the gradual change conversion direction in real time); in the second mode, once the gradual transition process is entered, the change direction of the integral signal is locked, that is, the current gradual transition direction is locked, the second comparison signal is not responded and the gradual transition direction is not changed until the gradual transition process is completed, or the second comparison signal is responded again within a period of time after the gradual transition process is completed, for example, at least one pulse period, and whether to change the operating loop is determined according to the type of the second comparison signal, specifically, the above functions can be implemented by providing a device with a hysteresis function, for example, a hysteresis comparator, or a trigger circuit with a set reset function, or a circuit with a latch/unlock function, since the above devices with hysteresis function, trigger circuit with a set reset function, and circuit with a latch/unlock function can all be implemented by the known technologies in the art, this specification will not be described in detail.

In addition, in order to avoid that, in some extreme cases, the mains voltage fluctuates repeatedly to cause the driving circuit 100 to switch repeatedly in the gradual change process or between different loops, the control unit 110 may be configured to make the driving circuit 100 gradually change to the mains voltage corresponding to the main loop slightly higher than the mains voltage corresponding to the gradual change circuit to the bypass loop, so as to form a hysteresis window, for example, by setting the second comparator 113 in the electrical signal measuring unit 111 as a hysteresis comparator. In this embodiment, the gradual transition between different loops makes the light emission of the LED array not suddenly change when the driving circuit 100 is gradually transitioned from the current loop to the target loop due to the fluctuation of the mains voltage, which is beneficial to reducing or eliminating or improving the visual instantaneous brightness fluctuation perceivable to human eyes, and after the gradual transition is completed, the driving circuit 100 continuously operates in a fixed loop or a combination of loops, thereby reducing or eliminating the low-frequency stroboflash.

Taking n-2 and m-1 as an example, an operation waveform diagram corresponding to the driving circuit 2 shown in fig. 11 is shown in fig. 43, in which the horizontal axis is a time axis, the vertical axis vdc (T) corresponds to a pulsating direct-current voltage after alternating current rectification, the vertical axis ILED2(T) corresponds to a current of the second LED array LED2 that can be bypassed by the switching unit Q1, the vertical axis ILED1(T) corresponds to a current of the first LED array LED1, the vertical axis IQ1(T) corresponds to a current of the switching unit Q1, and the vertical axis IQ0(T) corresponds to a current of the current limiting device Q0. Before time T001, the minimum value of the pulsating direct current voltage vdc (T) is continuously sufficient to drive the two LED arrays, the switching unit Q1 is turned off (or turned off), and the currents of the first LED array LED1 and the second LED array LED2 are controlled by the current limiting device Q0.

As shown in fig. 11, x is 0, m is 1, n is 2, q is 1, p is 2, and y is 0. When the control circuit 1 is used/applied to two LED arrays, the positive polarity end of the pulsating direct voltage, the first LED array LED1, the second LED array LED2 are connected in sequence to constitute a series circuit. The switching unit Q1 is connected across the following 1) and 2): 1) the junction of the first LED array LED1 and the second LED array LED2, and 2) the negative side of the pulsating dc voltage. Thus, in response to at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the conduction threshold, the control switch unit Q1 of the control unit D1 remains conductive for a full period of the pulsating direct current voltage, whereby, during a full period of each pulsating period of the subsequent pulsating direct current voltage, the first LED array LEDs 1 are individually illuminated and the second LED array LEDs 2 are not illuminated. The turn-on threshold may include a plurality of specific values, such as a full bright threshold in this embodiment, depending on the value of the turn-on voltage drop of each LED array, the circuit connection structure, and other factors. Here, the state of locking the first LED array LEDs 1 to be lit individually may last at least one pulse cycle, for example, several pulse cycles corresponding to the time period T002-T003, until the minimum value of the pulse voltage occurs again, for example, around the time T003, a certain degree of up-and-down change crosses some threshold or voltage interval of the turn-on threshold again.

In addition, in some embodiments, as shown in fig. 21, the n LED arrays driven by the control circuit 8 further include a third LED array D23 connected in series in the series circuit formed by the first LED array D21, the second LED array D22 and the dc power supply 07. The m switch units further include a first switch unit SW 21. When the control circuit is applied to the first LED array, the second LED array and the third LED array in the series circuit, the first switching unit will correspond to the first LED array and be connected in parallel with the first LED array D21. Thus, in response to at least one electrical signal indicating that the minimum value of the pulsating direct current voltage 07 falls below the full bright threshold (e.g., insufficient to simultaneously turn on the first LED array D21 and the second LED array D22, but sufficient to turn on either one of them alone), the first LED array D21 and the second LED array D22 are alternately lit at the first predetermined frequency by the timing logic circuit 5 alternately outputting temporally complementary control signals to the control terminals of the first LED array D21 and the second LED array D22, respectively, at the first predetermined frequency. In addition, since the third LED array D23 is not bypassed by any switching unit, it can be in a normally on state.

At time T001, control unit D1 detects or predicts that the value of pulsating dc voltage vdc (T) is insufficient to drive both LED arrays at least at one time or time interval, and enters a gradual transition process: by gradually increasing the on-time of the switching unit Q1 (i.e. the time of the bypass loop operation) or the ratio of the on-time of the switching unit Q1 to the off-time of the switching unit Q1 by the same amount or by unequal amounts in synchronization or non-synchronization with the fixed interval time (or the non-fixed interval time) of the pulse cycle, the average value of the current and the brightness of the second LED array LED2 gradually decrease until the time T002, the switching unit Q1 continues to be turned on, and the second LED array LED2 is bypassed and turned off.

Specifically, for example, the integrating unit 114 is composed of an up-down counter and a digital-to-analog converter, the pulsating dc voltage vdc (T) value is insufficient to drive the two LED arrays at least at one time or within a time interval, the up-down counter receives the rising/falling edge of the second comparison signal, the output terminal of the up-down counter outputs a changed (e.g., increased) count signal, and outputs an integrated signal corresponding to the count signal to the first comparator 116 through the digital-to-analog converter, the first comparator 116 outputs a comparison signal according to the comparison result between the integrated signal and the first electrical signal, the signal processing unit 112 increases the on-time of the switching unit Q1 in response to the output of the first comparator 116 until the time T002, and the gradual transition process is completed, and the operation process inside the control unit in the gradual transition process is not described again.

In the time interval between T002-1 to T003-1, the minimum value of the pulsating direct voltage vdc (T) is continuously insufficient to drive both LED arrays, the switching unit Q1 is turned on, the current of the second LED array LED2 is continuously zero, and the current of the first LED array LED1 is continuously regulated by the switching unit Q1.

During at least one pulsing period before time T003, control unit D1 detects that the minimum value of the pulsating direct voltage vdc (T) is sufficient to drive both LED arrays, entering the ramp transition process: by reducing the on time of the switching unit Q1 or the ratio of the on time of the switching unit Q1 to the pulse cycle by the same amount or by unequal amounts at fixed intervals (or unfixed intervals) that are synchronous or asynchronous with respect to the pulse cycle, the average value of the current and the brightness of the second LED array LED2 gradually increase until the time T004 or a period after T004, the switching unit Q1 continues to be turned off, the second LED array LED2 continues to be turned on, and the currents of the first LED array LED1 and the second LED array LED2 are controlled by the current limiting device Q0.

After time T004, the minimum value of the pulsating direct current voltage vdc (T) is continuously sufficient to drive the two LED arrays in series, the switching unit Q1 is continuously turned off (or turned off), and the current of the first LED array LED1 and the second LED array LED2 is controlled by the current limiting device Q0.

During and before and after the above-mentioned ramp transition, the current through the main loop or the bypass loop is configured to be the same, which is advantageous for the power supply system, for example, when the value of the pulsating direct voltage vdc (t) is at the critical point just triggering the transition of the different loops, since the value of the current drawn from the direct current power supply by the different loops before and after the transition is substantially constant, and thus the power drawn from the pulsating direct current power supply is also substantially constant. However, in some cases, it may be more desirable to stabilize the brightness of the lighting device, and accordingly, the current of the first LED array LED1 when the switch unit Q1 is turned on may be set to be larger than the currents of the first LED array LED1 and the second LED array LED2 adjusted by the current limiting device Q0 when the switch unit Q1 is turned off, so as to reduce the variation of the light emission amount by controlling the sum of the powers of the LED arrays to be approximately constant, which is described in detail in other embodiments of the present invention and will not be described herein again.

Alternatively, the current of the LED array 1 when the switching unit Q1 is turned on may be set to be smaller than the currents of the LED2 array 1 and the LED array 2 adjusted by the current limiting device Q0 when the switching unit Q1 is turned off, so that the light emitting brightness of the LED array is reduced as the pulsating direct current voltage vdc (t) is reduced, thereby simulating the light emitting characteristics of the incandescent lamp.

Alternatively, in conjunction with fig. 11, during the gradual transition, the current in the main loop and the bypass loop may also be gradually converted, for example, the current of the current limiting device and the switching unit may be directly adjusted by integrating the signal, and the corresponding waveforms are as shown in fig. 44, where the horizontal axis is a time axis, the vertical axis vdc (T) corresponds to a pulsating dc voltage after rectification of the ac, the vertical axis ILED2(T) corresponds to the current of the second LED array LED2 that can be bypassed by the switching unit Q1, the vertical axis ILED1(T) corresponds to the current of the first LED array LED1, the vertical axis IQ1(T) corresponds to the current of the switching unit Q1, and the vertical axis IQ0(T) corresponds to the current of the current limiting device Q0. Specifically, implementation details and motion waveforms are not repeated.

When n is 3 and m is 2, in conjunction with the drive circuit 100 shown in fig. 45, fig. 46 shows an operation waveform in which the magnitude of the shaded portion corresponds to the current at the time of alternating on/off, and since the average value of the current at the time of alternating on/off is smaller than that at the time of continuous on, a distinction is made with a relatively small magnitude in fig. 46.

A vertical axis vrec (T) corresponds to the rectified pulsating direct current voltage of the alternating current, a vertical axis IB2(T) corresponds to the current of the LED array B2 that can be bypassed by the switching unit ASW1, a vertical axis IB1(T) corresponds to the current of the LED array B1 that can be bypassed by the switching unit a1, a vertical axis IB3(T) corresponds to the current of the LED array B3 without the corresponding switching unit, a vertical axis IASW1(T) corresponds to the current of the switching unit ASW1, a vertical axis IA1(T) corresponds to the current of the switching unit a1, a vertical axis IA2(T) corresponds to the current of the current limiting device a2, and a vertical axis VB123(T) corresponds to the sum of the conduction voltage drops of the LED array B1, the LED array B2, and the LED array B3, and a vertical axis VB3(T) corresponds to the conduction voltage drop of the LED array B3. And assume that LED array B1 and LED array B2 are identical.

Before time T001, the minimum value of the pulsating direct voltage vrec (T) is continuously sufficient to drive the three LED arrays, with both the floating switch unit ASW1 and the common switch unit turned off (or turned off).

At time T001, control unit X2 detects or predicts that pulsating dc voltage vrec (T) is insufficient to drive three LED arrays at least at one time or time interval, entering a slow conversion process: the on time of the two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common switch unit a1 is increased by the same amount or an unequal amount at a fixed interval (or an unfixed interval) that is synchronous or asynchronous with the pulsation cycle, and the on time of the main circuit is decreased by the same step until the time T002, the two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common switch unit a1 are continuously operated.

In the time interval between T002-1 and T003-1, the minimum value of the pulsating direct current voltage VREC (T) is continuously insufficient to drive the three LED arrays, and two bypass loops formed by the alternate on/off of the floating ground switch unit ASW1 and the common ground switch unit A1 are continuously operated.

During at least one pulse period before time T003, control unit X2 detects that the minimum value of the pulsating direct voltage vrec (T) is sufficient to drive three LED arrays continuously, entering the gradual transition process: the on time of the two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common ground switch unit a1 is reduced by the same amount or an unequal amount at a fixed interval (or an unfixed interval) that is synchronous or asynchronous with the pulsation cycle, and the on time of the main circuit is increased by the same step until the time T004, and the operation is continued in the main circuit.

After time T004, the minimum value of the pulsating direct current voltage vrec (T) is continuously sufficient to drive the three LED arrays, and the floating switch unit ASW1 and the common ground switch unit a1 are both turned off (or turned off), and continuously operate in the main loop.

Fig. 47 shows an operation waveform corresponding to a further decrease in the pulsating dc voltage vrec (t) in conjunction with fig. 45.

A vertical axis vrec (T) corresponds to the rectified pulsating direct current voltage of the alternating current, a vertical axis IB2(T) corresponds to the current of the LED array B2 that can be bypassed by the switching unit ASW1, a vertical axis IB1(T) corresponds to the current of the LED array B1 that can be bypassed by the switching unit a1, a vertical axis IB3(T) corresponds to the current of the LED array B3 without the corresponding switching unit, a vertical axis IASW1(T) corresponds to the current of the switching unit ASW1, a vertical axis IA1(T) corresponds to the current of the switching unit a1, a vertical axis IA2(T) corresponds to the current of the current limiting device a2, and a vertical axis VB123(T) corresponds to the sum of the conduction voltage drops of the LED array B1, the LED array B2, and the LED array B3, and a vertical axis VB3(T) corresponds to the conduction voltage drop of the LED array B3.

Before time T001, the minimum value of the pulsating direct-current voltage vrec (T) is insufficient to drive three LED arrays, but is sufficient to drive the LED arrays of two bypass circuits formed by the floating switch unit ASW1 and the common ground switch unit a1 alternately turned on/off, and the two bypass circuits formed by the floating switch unit ASW1 and the common ground switch unit a1 alternately turned on/off are continuously operated.

At time T001, the control unit X2 detects or predicts that the pulsating dc voltage vrec (T) is insufficient to drive the LED arrays of the two bypass loops formed by the floating switch unit ASW1 and the common switch unit a1 alternately on/off at least at one time or time interval, entering the gradual transition process: the on time of the bypass circuit formed by the array B3 of the dc power supply U, LED, the floating switch unit ASW1 and the common ground switch unit a1 is increased by the same amount or unequal amount at a fixed interval (or a non-fixed interval) which is synchronous or asynchronous with the ripple cycle, and the on time of two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common ground switch unit a1 is reduced by the same step, until the time T002, the bypass circuit formed by the array B3 of the dc power supply U, LED, the floating switch unit ASW1 and the common ground switch unit a1 is continuously operated.

In the time interval between T002-1 and T003-1, the minimum value of the pulsating direct current voltage VREC (T) is continuously insufficient to drive the LED array of the two bypass loops formed by the alternate on/off of the floating switch unit ASW1 and the common ground switch unit A1, and the driving circuit 100 is continuously operated in the bypass loop formed by the direct current power supply U, LED array B3, the floating switch unit ASW1 and the common ground switch unit A1.

During at least one pulse cycle before the time T003, the control unit X2 detects that the minimum value of the pulsating direct-current voltage vrec (T) is continuously enough to drive the LED arrays of the two bypass loops formed by the floating switch unit ASW1 and the common ground switch unit a1 alternately on/off, entering the gradual transition process: the on time of the bypass circuit formed by the pulsating direct-current power supply, the LED array B3, the floating switch unit ASW1 and the common ground switch unit a1 is reduced by the same amount or unequal amount at a fixed interval (or a non-fixed interval) which is synchronous or asynchronous with the pulsation cycle, and the on time of the two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common ground switch unit a1 is increased by the same step until the time T004, and the driving circuit 100 continues to operate in the two bypass circuits formed by alternately turning on/off the floating switch unit ASW1 and the common ground switch unit a 1.

After time T004, the minimum value of the pulsating direct current voltage vrec (T) is continuously sufficient to drive the LED array of the two bypass loops formed by the floating switch unit ASW1 and the common ground switch unit a1 being alternately turned on/off, and continuously operates in the two bypass loops formed by the floating switch unit ASW1 and the common ground switch unit a1 being alternately turned on/off.

Constant power/high frequency alternately lighting LED

Fig. 27 is a functional block diagram of a driving circuit and a lighting device capable of operating a control method according to another embodiment of the present invention. In the figure, the plurality of light emitting loads n _ LED includes: the light emitting loads LED _ N1, the light emitting load LED _ N2, the light emitting load LED _ N3, the light emitting load LED _ N4, and the light emitting load LED _ N5 are connected in series, and each light emitting load positive polarity terminal is connected to the negative polarity terminal of the light emitting load adjacent thereto. The 5 series-connected lighting loads are supplied by a dc power supply Volt _ 1.

Fig. 27 a-27 c are various variations of a lighting load or LED array of fig. 27 and other embodiments of the present invention. Wherein each lighting load, solid state lighting load, or LED array may include a plurality of LED units in series, a plurality of LED units in parallel, and a plurality of LED units in a series-parallel combination. For example, taking LED _ N3 as an example, it may be implemented as a plurality of LED units LED _ N3 'connected in series as shown in fig. 27a, a plurality of LED units LED _ N3 "connected in parallel as shown in fig. 27b, or a plurality of LED units LED _ N3"' combined in series and parallel as shown in fig. 27 c. It should be understood that variations of lighting loads, solid state lighting loads, or LED arrays, including those illustrated in fig. 27 a-27 c, may be applied to all relevant embodiments of the present invention. And may not be described in further detail elsewhere.

Fig. 34 is a schematic diagram illustrating voltages of different levels provided by a dc power supply for supplying power to a lighting load and a driving circuit thereof and corresponding regulated currents in the lighting load according to an embodiment of the present invention.

A method for controlling a lighting load according to an embodiment of the present invention is described below with reference to fig. 27 and 34, wherein the exemplary description is based on a lighting load of an LED type but should be understood by those skilled in the art: the method may also be applicable to some other type of light emitting load than a light emitting diode.

As shown in fig. 27, the dc power source Volt _1 may be a rectifying unit, an input terminal (not shown) of which is connected to the external power grid, and an output terminal of which is coupled to the above-mentioned 5 light-emitting loads to provide a rectified pulsating dc voltage. Alternatively, the dc power source Volt _1 may be a battery, such as a storage battery, a dry battery, etc., which has a dc regulated voltage, and may be regarded as a constant voltage, or a dc voltage with a slightly fluctuating amplitude (e.g., ± 0.5% or ± 0.05%, etc.).

Alternatively, the lighting load may be an array of light emitting diodes or the like. Those skilled in the art will understand that: the above-mentioned lighting load of 5 LED types requires the dc power supply Volt _1 to have a certain operating voltage Volt _ NORM, so that all of them can be normally turned on/turned on. It is assumed that ideally, the output voltage of the dc power supply Volt _1 may all fall on the n light emitting loads n _ LED, and there is no other voltage dividing device. When all the n light-emitting loads n _ LED are turned on, the turn-on voltage drop is the voltage Volt _ NORM, and the current flowing through the n light-emitting loads n _ LED is ILED _ NORM.

In some application scenarios, the dc power supply Volt _1 may be lower than the operating voltage Volt _ NORM. This results in that the 5 light-emitting loads cannot be all lit due to insufficient voltage. As shown in fig. 34, for example, the output voltage of the dc power supply Volt _1 is only maintained at the level of Volt _ low1, so that only 4 lighting loads of the plurality of lighting loads N _ LED can be turned on/on, and therefore, in the present embodiment, a subset of the 5 lighting loads, or a part (but not all) of the lighting loads, is dynamically combined to form a new LED series circuit by bypassing the lighting loads LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 through the control unit coupled to the plurality of lighting loads. The LED series circuit has less light emitting load and thus requires a lower voltage to be turned on.

The embodiment also provides a control method of the LED array, which comprises the following steps: at a driving circuit for driving n mutually coupled LED arrays powered by a dc power supply, in conjunction with fig. 7 and table 2, the three LED arrays are divided into two groups, where the number of LED arrays in the first group is two, and then the first group includes three partial LED arrays, respectively first partial LED arrays: a first LED array LED1 and a second LED array LED 2. A second partial LED array: a first LED array LED1 and a third LED array LED 3. Third partial LED array: a second LED array LED2 and a third LED array LED 3.

In the second group, the number of the LED arrays is one, and the second group includes three partial LED arrays, which are respectively the first partial LED arrays: first LED array LED 1. A second partial LED array: second LED array LEDs 2. And a third partial LED array: third LED array LED 3.

The control method of the LED array described hereinbefore comprises steps SA-1) and SA-2), in which:

SA-1): in response to/if the output voltage of the dc power source U is greater than or equal to the turn-on threshold, driving to illuminate one of i) all three LED arrays, or ii) a first set of at least one partial LED array of the three LED arrays;

SA-2): and in response to/if the output voltage of the direct current power supply U is lower than the conduction threshold value, driving to light one of a second group of at least one partial LED array in the n LED arrays.

Optionally, in some embodiments, one of the second group of at least one partial LED array has the most/next most or the largest/next most conducting voltage drop in the second group of at least one partial LED array, for example, when the conducting voltage drops of the first to third LED arrays are not equal to each other, assuming that V1 > V2 > V3, the largest conducting voltage drop V1+ V2 is provided in the second group of at least one partial LED array, that is, the first partial LED array: a first LED array LED1 and a second LED array LED 2. Or, the second group has the second largest conducting voltage drop V1+ V3 in at least one part of the LED arrays, that is, the second part of the LED arrays: a first LED array LED1 and a third LED array LED 3.

By the arrangement, the driving circuit can still operate in a bypass loop or a bypass loop combination with high energy conversion efficiency when the output voltage of the direct-current power supply U is insufficient.

Alternatively, in some embodiments, the turn-on threshold may take different specific values, such as threshold a (70 volts), threshold B (180 volts), and so on, depending on different operating states of the driving circuit, different configurations of the dc power supply, and so on. The turn-on threshold may comprise a full bright threshold (e.g., 215 volts), above which the output voltage of the dc power supply U is sufficient to turn on all n LED arrays.

In order to solve the application scenario that the direct-current power supply supplies power to the driving circuits of the n LED arrays connected in series, the invention provides a control method of a luminous load of one embodiment, which comprises the following two steps: step SA-1) drives the n light-emitting loads to be lit when the voltage of the dc power supply is higher than the voltage Volt _ NORM of the full lighting threshold enough to turn on the n light-emitting loads.

Step SA-2) drives the n light-emitting loads to be partially lit when the dc power supply has a voltage Volt _ low1 lower than the full lighting threshold insufficient to turn on the n light-emitting loads.

When the dc power supply Vlot _1 has a voltage Volt _ NORM exceeding the full bright threshold value to turn on all of the n light-emitting loads n _ LED, the current ILED _ NORM flows through the n light-emitting loads n _ LED. The power of the n light-emitting loads n _ LED is defined as a first power value, and the specific value of the first power value may be different according to the specific application scene and the electrical characteristics of the driving circuit/lighting device.

When the dc power supply Volt _1 has a voltage Volt _ low1 lower than the full brightness threshold, only the first partial LED array of the n light-emitting loads n _ LEDs is turned on in step SA-2. Thereby, the light emission state of the n light emission loads n _ LED as a whole can be maintained without being completely extinguished due to insufficient voltage.

Optionally, in the LED array control method of some embodiments of the present invention, step SA-2) may further include sub-steps SA-2-1): the current through the n light-emitting loads n _ LED is regulated in substantially the opposite direction/negative dependence of the conduction voltage drop of the n light-emitting loads n _ LED, so that the power of the n light-emitting loads is kept in the vicinity of the first power value. Here, only a first partial LED array of the N lighting loads N _ LED is turned on, while the LED array LED _ N5 is bypassed/extinguished. The conduction voltage drop of the n light-emitting loads n _ LED is also the conduction voltage drop of the first part of LED array, and the conduction voltage drop of the first part of LED array is smaller than the conduction voltage drop when all the n light-emitting loads n _ LED are conducted.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2-1-1) thereof may further comprise the sub-steps of: and in response to the partial LED arrays being independently lighted, increasing the current in the partial LED arrays to be larger than the current flowing when the n light-emitting loads n _ LED are all turned on so as to keep the power of the n light-emitting loads n _ LED in the neighborhood of the first power value. For example, the current in the conducting first part of the LED array is (actively) regulated by the control unit to be larger than the current ILED _ NORM when all of the n light-emitting loads n _ LED are conducting, so as to compensate to some extent the power drop caused by the insufficient voltage with respect to when all of the n light-emitting loads n _ LED are conducting.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2-1) or similar steps therein may further comprise the sub-step SA-2-1-1) of coordinating i) the current flowing when the N light emitting loads N _ LEDs are all turned on, and ii) the current when the partial LED arrays are individually turned on, such that the power when the N light emitting loads N _ LEDs are all turned on and the power of the individually turned on partial LED array LED _ N4 are both kept within the neighborhood of the first power value. In other words, in two states of the lighting device Light _1, in which the n Light-emitting loads are all turned on and only part of the LEDs are turned on, the power of the n Light-emitting loads n _ LEDs is kept substantially the same.

Specifically, the n lighting loads are 5 LED arrays, and the first partial lighting load includes a first partial LED array. The LED array control method of some embodiments of the present invention, or step SA-2-1-1) or similar steps therein, may further include sub-steps I) and II). In sub-step I), when the dc power supply has a voltage Volt _ NORM higher than the full brightness threshold, if the output voltage of the dc power supply Volt _1 is floating, the current ILED _ NORM in the 5 LED arrays n _ LED is boosted as the output voltage of the dc power supply Volt _1 decreases. The current ILED _ NORM in the 5 LED arrays n _ LED is reduced as the voltage of the dc power supply Volt _1 increases. And, in sub-step II), when the first part of LED arrays are turned on alone or the voltage of the dc power supply Volt _1 is lower than the full bright threshold, increasing the current in the first part of LED arrays as the turn-on voltage drop of the first part of LED arrays decreases; and reducing the current in the first part of LED arrays along with the increase of the conducting voltage drop of the first part of LED arrays. Of course, if the on-voltage drop of the LED arrays of the first part remains substantially constant, the current in the LED arrays of the first part can be adjusted to remain substantially constant by the control circuit control _ 1. Thus, during the variation of the voltage of the dc power supply Volt _1, the power of the 5 LED arrays as a whole is kept within the neighborhood of the first power value, and correspondingly, the overall/luminous flux of the 5 LED arrays is also kept substantially constant.

For example, to ILED _1 in inverse proportion to the on-voltage drop of the n lighting loads n _ LED. Thereby, the power of the n light emitting loads is kept in the neighborhood of the first power value. Since the n light-emitting loads n _ LED all have the first power value when turned on, the (overall) power of the n light-emitting loads n _ LED and thus the resulting luminous flux can be kept (substantially) constant, although the voltage of the dc power supply Vlot _1 drops.

Of course, it will be understood that: the voltage Volt _ low1 at the dc supply Volt _1, although lower, may be sufficient to turn on the second partial LED array alone in addition to the first partial LED array alone.

Optionally, the LED array control method of some embodiments of the present invention or step SA-2) or similar steps therein, and sub-steps of these steps may further include the steps of: when the voltage of the dc power supply Volt _1 is maintained at the voltage level Volt _ low1 (below the full lighting threshold), it is sufficient to switch on the second partial LED array alone (or also the third partial LED array) in addition to the first partial LED array. Only a part of the LED arrays is turned on at any time except for the first part of the LED arrays and the second part of the LED arrays during a short switching transition, which may accommodate the low voltage level Volt _ low1 of the dc power supply Volt _ 1. Meanwhile, the first part of LED arrays and the second part of LED arrays are lightened along with time, so that normally-off LED arrays do not exist in the 5 LED arrays, electric energy obtained from a direct-current power supply Volt _1 is distributed to the 5 LED arrays, and the distribution effect of luminous flux is improved.

In other scenarios, the dc power source Volt _1 may be a rectifying unit, the input terminal (not shown) of which is connected to the external power grid, and the output terminal of which is coupled to the above-mentioned 5 light-emitting loads to provide a rectified pulsating dc voltage. The pulsating direct current voltage has a relatively obvious variation amplitude, and in the floating process, different voltage intervals may occur, one voltage interval may be above a full-bright threshold, and other voltage intervals are optionally all below the full-bright threshold, so that all 5 LED arrays are not sufficiently turned on.

Fig. 35 is a waveform diagram illustrating two LED arrays alternately turned on in a first voltage interval according to an embodiment of the invention. Referring to fig. 35, a scenario in which the dc power supply Volt _1 supplies a periodically varying voltage, for example, a pulsating dc voltage, to the 5 LED arrays is explained, and in the periods T1-T2 and T3-T4, and T1 '-T2' and T3 '-T4' of fig. 35, a first voltage interval Interv _1 occurs four times in the output voltage V21(T) of the dc power supply Volt _1, and is lower than a full-bright threshold and is insufficient to turn on all the n LED arrays. Correspondingly, with such a pulsed dc voltage supply as shown in fig. 22, the LED array control method of some embodiments of the present invention or step SA-2) or similar steps therein, and the sub-steps of these steps may further comprise any of 4 sub-steps including the alternative (alternative) two sub-steps 1), 2) in step SA-2-a) below, or the alternative (alternative) two sub-steps 3), 4) in step SA-2-b):

SA-2-a) -substep 1), in response to the voltage V21(T) of the dc power supply Volt _1 being located in a first voltage interval, a plurality of subsets/portions of the n LED arrays corresponding to the first voltage interval, e.g. a first portion of LED arrays, a second portion of LED arrays, are cyclically turned on/on for the duration of the first voltage interval. When the voltage of the dc power supply Volt _1 is within any voltage sub-interval or at any voltage level in the first voltage interval, the first part of LED arrays and the second part of LED arrays may be alternately turned on (for example, at a high frequency of several tens of k). It should be noted that, in the above-mentioned embodiment and other related embodiments of the present invention, the voltage V21(T) of the dc power supply Volt _1 is located at any voltage level in the first voltage interval Interv _1 by driving of the control unit Contr _1, and both the first part of LED arrays and the second part of LED arrays can be turned on alternately (for example, at a high frequency of several tens k). In other words, the alternate conduction between the second part of LED arrays and the first part of LED arrays in some embodiments of the present invention may be actively initiated by the control unit Contr _1 at any time of the first voltage interval; the first voltage interval may also be arbitrarily small, or the range of the first voltage interval may also be smaller than the conduction voltage drop of any one of the n LED arrays, which means that when the output voltage of the dc voltage Volt _1 decreases from the upper limit voltage level to the lower limit voltage level of the first voltage interval, the number of LED arrays that can be conducted by the output voltage in the n LED arrays is unchanged, but in the driving circuit/control method according to some embodiments of the present invention, the control unit may still actively initiate the alternate conduction or the alternate conduction of a plurality of subsets/parts of LEDs (a subsets/locations of LED arrays) in the n LED arrays. The alternate/alternate conduction in this embodiment is different from the following case: the voltage level of the dc power supply spans different low voltage intervals, causing alternating conduction of passive responses in the first, second or further LED arrays, for example: and switching on the first part of LED arrays in the first low voltage interval, switching on the fourth part of LED arrays in the second voltage interval, switching on the fifth part of LED arrays in the third voltage interval, … …, and the like, wherein the voltages in the first voltage interval, the second voltage interval and the third voltage interval are sequentially reduced, the switching-on voltage drops of the corresponding first part of LED arrays, the fourth part of LED arrays and the fifth part of LED arrays which are switched on are also sequentially reduced, and the quantity of the LED arrays is possibly also sequentially reduced. The description herein applies to the apparatus, methods, and steps of the other related embodiments as well.

SA-2-a) -substep 2), a plurality of subsets of the n arrays corresponding to first voltage intervals, e.g., a first subset of LED arrays, a second subset of LED arrays, are alternately turned on/illuminated for the duration of each of a plurality of first voltage intervals, e.g., 4 as shown in fig. 35. Here and in other related embodiments of the apparatus, method and steps thereof, the conducting states state _ N4 and state _ N5 of the first part LED array and the second part LED array are complementary to each other as shown in fig. 35, and each has a certain duty ratio in time domain, for example, 50% respectively. And the first voltage section has a voltage range below the full bright threshold.

SA-2-b) -substep 3), a first voltage interval Interv _1 is periodically generated in response to a variation in the voltage V21(T) of the dc power supply Volt _1, cycling on a plurality of subsets of the n arrays corresponding to the first voltage interval, for example, a first portion of LED arrays, a second portion of LED arrays. Fig. 35 shows that the frequency of the alternate conduction is greater than, less than, or equal to the frequency of the voltage change of the dc power supply, and is a case where the frequency of the alternate conduction is greater than the frequency of the voltage change of the dc power supply Volt _ 1: in a pulse cycle, the first voltage interval occurs two times, and more than three times alternately conduct for the duration of a voltage interval, as shown in the figure. By such higher frequency alternating/cyclic conduction, the power of the n LED arrays can be distributed more evenly in space over time (over time), further reducing stroboscopic effects.

Substep 4) alternately lighting a plurality of subsets of the n arrays corresponding to the first voltage interval Interv _1, a first portion of LED arrays and a second portion of LED arrays for the duration of a plurality of first voltage intervals Interv _ 1. One of the first voltage intervals inters _1, or two or more consecutive voltage intervals inters _1, corresponds to only one of the subsets. In other words, only one of the plurality of subsets is illuminated in 1 of the plurality of first voltage intervals, or 2-5 consecutive. That is, for example, in fig. 35, only the first part of the LED arrays are lit for the duration of the first 2 of the 4 first voltage intervals Interv _1, and the second part of the LED arrays are switched to be lit for the duration of the last 2 first voltage intervals Interv _1 until the first part of the LED arrays (not shown in the figure) are lit. Of course, the first voltage section has a voltage range that is below the full bright threshold.

In addition, the cycle on or the alternate lighting means: the LED arrays of the plurality of subsets, such as the second part LED array and the first part LED array, are repeatedly lighted in sequence, i.e., sub-step 4, etc. are performed cyclically/repeatedly as the first voltage interval Interv _1 is repeated. Of course, it should be understood that the two are referred to as alternate conduction, and the three and above are referred to as cyclic conduction. Thus, optionally, a third partial LED array (e.g., LED array LED _ N4) may also be present, and the first, second, and third partial LED arrays may be cycled on.

In addition, it is worth noting: a two-part LED array that is alternately switched on can be understood as: each comprising only one LED array, i.e. the second part of LED arrays comprises only LED _ N5 and the first part of LED arrays comprises only LED _ N4. In addition, if one alternates between two parts of LED arrays, in particular cycling/alternating on between LED arrays of three subsets of the first part of LED arrays, the second part of LED arrays and the third part of LED arrays, then this can also be understood as: there may be intersections. For example, 3 subsets of n LED arrays may be configured such that: the first part of LED arrays only includes 4 LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4, the second part of LED arrays only includes 4 LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N5, and the third part of LED arrays only includes 4 LED arrays LED _ N1, LED _ N2, LED _ N4 and LED _ N5. The description herein is also applicable to the control method or apparatus according to any other relevant embodiment of the present invention.

The first part of LED arrays and the second part of LED arrays are proper subsets of the n LED arrays, and no intersection exists between the first part of LED arrays and the second part of LED arrays. Optionally, in the LED array control method according to some embodiments of the present invention, if the first part of LED arrays and the second part of LED arrays do not intersect, the control method further includes: keeping a third partial LED array of the N lighting loads N _ LED normally on, for example, for the first voltage interval Interv _1, the third partial LED array may be any one or more of the lighting loads LED _ N1, LED _ N2, LED _ N3, wherein the lighting loads LED _ N1, LED _ N2, or LED _ N3 do not belong to the first partial LED array or the second partial LED array LED _ N5. The third partial LED array is connected in series with other LED arrays and keeps normally on, which improves the efficiency of the dc power supply Volt _1 supplying power to the n light-emitting loads n _ LEDs. Preferably, the third partial LED array has all the light emitting loads except the first partial LED array and the second partial LED array in the n light emitting loads in the first voltage interval, or the third partial LED array has the maximum number of light emitting loads except the first partial LED array and the second partial LED array in the n light emitting loads in the first voltage interval. Optionally, the third portion of LED arrays does not intersect with any of the first portion of LED arrays and the second portion of LED arrays.

Optionally, the corresponding plurality of subsets of the first voltage interval in the n LED arrays n _ LED are: a first portion of the LED array and a second portion of the LED array. In the LED array control method of some embodiments of the present invention, the step SA-2-a) further includes a sub-step SA-2-a-1): the first and second partial LED arrays are alternately turned on for the duration of the first voltage interval. Step SA-2-b) further comprises the sub-step SA-2-b-1): and respectively conducting the first part of LED array and the second part of LED array to two adjacent first voltage intervals in a cyclic mode. For example, when the dc power supply outputs a pulsating dc voltage, in the first pulsating cycle of fig. 35, first voltage intervals a and b (not labeled in the figure) appear twice in sequence, and are located on both sides of the peak value of the first pulsating wave, in the first voltage interval a, only the first part of the LED arrays are turned on, and in the first voltage interval b, the second part of the LED arrays are turned on individually. In this way, the first part of the LED array and the second part of the LED array are cyclically switched on in the subsequent pulsing period. In this case, the period/frequency of the cyclic conduction of the first partial LED array and the second partial LED array can be regarded as the same as the period/frequency of the pulsating dc voltage of the dc power supply.

Of course, alternatively, in two different first voltage intervals a and b occurring successively in the first ripple period described above, only the first part of the LED array may be turned on, and in two first voltage intervals occurring in the subsequent second ripple period, only the second part of the LED array may be turned on, in which case the frequency of the cyclic conduction of the first part and the second part of the LEDs may be considered to be less than the frequency of the ripple dc voltage V21(T) of the dc power supply. Further alternatively, in the single first voltage interval a in the first pulse period, the first partial LED array and the second partial LED array may be turned on alternately for a plurality of times (for example, hundreds of times), and the alternating frequency thereof is greater than the frequency of the pulsed dc voltage of the dc power supply. The larger frequency of alternating/alternating conduction may distribute the power/optical power/luminous flux more evenly over time over the n luminous loads, or each luminous load may share (share) the overall luminous flux more frequency-divisionally, which reduces the stroboflash and also may bring better user experience due to the principle of persistence of vision.

Alternatively, in two different first voltage intervals a and b occurring successively in the first ripple period described above, only the second part of the LED arrays may be turned on, and in two first voltage intervals occurring in the subsequent second ripple period, only the second part of the LED arrays may be turned on, in which case, the frequency of the alternate turning on of the first part of the LED arrays and the second part of the LED arrays may be regarded as being less than the frequency of the ripple dc voltage of the dc power supply. Further alternatively, in the single first voltage interval a in the first pulse period, the first partial LED array and the second partial LED array may be turned on alternately for a plurality of times (for example, hundreds of times), and the alternating frequency thereof is greater than the frequency of the pulsed dc voltage of the dc power supply.

Optionally, the number of LED arrays in the union of the first part of LED arrays and the second part of LED arrays that are cyclically/alternately turned on is greater than the maximum number of LED arrays in the n LED arrays that the first voltage interval is sufficient to light up. For example, the n LED arrays include 5 LED arrays: LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5. The LED arrays LED _ N1, LED _ N2 and LED _ N5 belong to the first part of LED arrays, and the LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4 belong to the second part of LED arrays. And the first voltage interval is not enough to turn on all 5 LED arrays but only LED _ N1, LED _ N2, LED _ N3, LED _ N4 because the first voltage interval is lower than the predetermined voltage threshold. In addition, the conduction voltage drop of the LED _ N5 is lower than the sum of the conduction voltage drops of the LED _ N3 and the LED _ N4, so the first voltage interval is also sufficient to turn on the first partial LED array. During the rotation, the union of the first partial LED arrays LED _ N1, LED _ N2, LED _ N5 and the second partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 covers LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5. That is, if the rotation frequency is proper, all 5 LED arrays can have luminous flux generated in the first voltage interval. In other words, when the first partial LED arrays LED _ N1, LED _ N2, LED _ N5 and the second partial LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4 are alternately turned on, the LED array which can emit light among the 5 LED arrays is a union of the first partial LED arrays LED _ N1, LED _ N2, LED _ N5, or the second partial LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4, and therefore, the light-emitting area of the N LED arrays is visually larger than the light-emitting area when the first partial LED arrays LED _ N1, LED _ N2, LED _ N5, or the second partial LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4 are individually turned on.

Alternatively, in the LED array control method of some embodiments of the present invention, in step SA-2-a-1) or the like, the alternate frequency of the rotation/alternate conduction is any one of [0.5kHz,1000kHz ].

Optionally, the circuit structure related to the control method/control method of this and other embodiments of the present application may be referred to in the related description including the summary under the heading "floating/common ground bypass".

Optionally, in the LED array control method of some embodiments of the present invention, a union of the first part LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 and the second part LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, where all of the no 5 LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5, covers/contains all of the N LED arrays or N-1 (the next largest number), thus, when the second partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N5 and the first partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 are alternately turned on, especially at high frequency, the (light source) light emitting area can be kept (basically) the same as that of the n LED arrays when the n LED arrays are all conducted by enough direct current power supply voltage, and stroboscopic is reduced to a great extent.

Optionally, the numbers of the first partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, the second partial LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5 are 4 maximum LED arrays that can be lit in the N LED arrays in the first voltage interval.

Optionally, in some embodiments, the number of the first partial LED arrays is the maximum number/next largest number of the LED arrays that can be lit in the n LED arrays in the first voltage interval, and in this embodiment, the number of the second partial LED arrays is the next largest number/maximum number of the LED arrays that can be lit in the n LED arrays in the first voltage interval. In this embodiment, the maximum number of LED arrays that can be lit by the dc power supply Volt _1 in the first voltage interval among the 5 LED arrays is 4, and the next largest number is 3. For example, the n LED arrays include 5 LED arrays: LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5. The arrays LED _ N1, LED _ N2 and LED _ N5 belong to the first part of LED array, and the arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N4 belong to the second part of LED array. Since the first voltage interval is not sufficient to turn on all 5 Led arrays but only 4 Led arrays below the predetermined voltage threshold: for example, LED _ N1, LED _ N2, LED _ N3, LED _ N4. In addition, the conduction voltage drop of the LED _ N5 is lower than the sum of the conduction voltage drops of the LED _ N3 and the LED _ N4, so the first voltage interval is also sufficient to turn on the first partial LED arrays LED _ N1, LED _ N2 and LED _ N5. During the rotation, the first part of LED arrays LED _ N1, LED _ N2, LED _ N5 have the next largest number of LED arrays that can be lit in 5 LED arrays with the first voltage interval: 3, the number of the medicine is less than that of the medicine. The second partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 have a first voltage interval of the maximum number of LED arrays that can be lit in 5 LED arrays: 4 of the Chinese herbal medicines. The more LED arrays in the LED arrays of the plurality of parts/subsets that are rotated, or the larger the conduction voltage drop, the higher the efficiency, and if the power is maintained substantially constant, the power is spread over more LED arrays by the rotation, so that the larger the (light source) light emitting area. Optionally, the number of the first part of LED arrays is the same as the number of the second part of LED arrays. For example, in the above-described embodiment, the n LED arrays include 5 LED arrays: LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5. The LEDs _ N1, the LEDs _ N2, the LEDs _ N3 and the LEDs _ N5 belong to a first part of LED arrays, and the LEDs _ N1, the LEDs _ N2, the LEDs _ N3 and the LEDs _ N4 belong to a second part of LED arrays. In addition, since the power of the first partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N5, the second partial LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5 are kept substantially the same, when the two partial LED arrays are alternately turned on, especially by high frequency, the same power is always dispersed over the same number of LEDs, thereby avoiding the flicker of light/dark due to the repeated concentration/dispersion of the same energy.

Optionally, in the LED array control method according to some embodiments of the present invention, the dc power supply Volt _1 outputs rectified pulsating dc voltage, the first part of LED arrays and the second part of LED arrays do not intersect with each other and have the same conduction voltage drop, correspondingly, in the alternate conduction process, the currents flowing through the first part of LED arrays and the second part of LED arrays are controlled by the switch unit to be square waves with complementary shapes or trapezoid-like square waves with smoother rising and falling edges, the amplitudes are substantially the same, and the duty ratios are 50% respectively, which is more favorable for brightness uniformity and improves the light emitting effect. Of course, it is understood that if the conduction voltage drops of the first part of LED arrays and the second part of LED arrays are different, the waveforms of the currents flowing in the first part of LED arrays and the second part of LED arrays may still be complementary in shape, but the amplitudes may optionally be different in inverse proportion to the voltage, and the duty cycle may not be 50% any more, but may be 4:6 or other ratios. One of the purposes is to adjust the power and luminous flux of the first partial LED array and the second partial LED array during the alternating conduction process, and the difference or stroboflash of the illumination effect caused by the alternating conduction to the outside is not substantially caused.

Optionally, in the LED array control method according to some embodiments of the present invention, the plurality of first voltage intervals occur periodically with the pulsating dc voltage. The first voltage intervals occur in time (over time) within the same voltage pulse cycle or are distributed over successive pulse cycles.

Optionally, in the LED array control method according to some embodiments of the present invention, the step SA-2-a-1) or SA-2-b-1) or similar step may further include: SA-2-ab-1) in the case of no intersection between the second partial LED array and the first partial LED array, the currents in the first partial LED array and the second partial LED array are coordinated during the alternating conduction such that the power of the n LED arrays is kept in the vicinity of the first power value. Alternatively, in case there is an intersection between the second partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 and the first partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4, the currents in the first partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 and the second partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 are coordinated during the cyclic/cyclic conduction such that the power of all 5 LED arrays is kept in the neighborhood of the first power value.

the current in the first LED array part LED _ N1, LED _ N2, LED _ N3, LED _ N4, and the second LED array part LED _ N1, LED _ N2, LED _ N3, LED _ N5 is adjusted according to the turn-on voltage drop of the first LED array part LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N1, LED _ N2, LED _ N3, LED _ N5, respectively, so that the relative rate of change of the power during the cycle of the turn-on of the first LED array part LED _ N1, LED _ N2, LED _ N3, LED _ N4, and the second LED array part LED _ N1, LED _ N2, LED _ N3, LED _ N5 is smaller than a predetermined percentage having a small value, wherein the predetermined percentage is smaller than 10%, smaller than 0.5%, or smaller than 5% of the value. Thereby, the first part LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 and the second part LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 are maintained, and the total luminous flux of the N LED arrays is substantially constant during the cycle of the alternate conduction. Optionally, in the LED array control method according to some embodiments of the present invention, step SA-2-ab-1) or similar steps may further include: step SA-2-ab-1-1) and step SA-2-ab-1-2)

In step SA-2-ab-1-1), during the switching from the first part of LED arrays to the second part of LED arrays, dynamically controlling the current in the first part of LED arrays to decrease synchronously with the increase of the current in the second part of LED arrays, so that the decrease of the power or luminous flux of the first part of LED arrays is compensated/counteracted by the increase of the power of the second part of LED arrays, and the total power of the first part of LED arrays and the second part of LED arrays is kept substantially the same during the switching from the first part of LED arrays to the second part of LED arrays.

Similarly, in step SA-2-ab-1-2), during the switching from the second part LED array to the first part LED array, the current in the second part LED array is dynamically controlled to decrease synchronously with the increase in the current in the first part LED array, so that the decrease in power or luminous flux of the second part LED array is compensated/offset by the increase in power of the first part LED array, and the overall power of the second part LED array is kept substantially the same as the total power of the second part LED array before and after the switching.

Fig. 17 is a current waveform diagram of a switch unit or a corresponding LED array in a switching transition state according to another embodiment of the present invention. Optionally, in the LED array control method according to some embodiments of the present invention, the step SA-2-ab-1-2) or the similar step may further include: as shown in fig. 17, in the transition process of switching from the second part of LED arrays to the first part of LED arrays, before the falling amplitude of the current in the second part of LED arrays exceeds the preset amplitude, the current in the first part of LED arrays is controlled to increase synchronously; and step SA-2-ab-1-1) further comprises: and in the transition process of switching from the first part of LED arrays to the second part of LED arrays, controlling the current in the second part of LED arrays to increase synchronously before the descending amplitude of the current in the first part of LED arrays exceeds a preset amplitude value. The preset amplitude value is optionally any value between 0% and 5%. Therefore, the overall power fluctuation is small in the transition process of mutually switching the second part of LED arrays and the first part of LED arrays in the dynamic control mode. Further reducing stroboscopic effects.

With the fluctuation of the pulsating direct current voltage vrec (t), the LED array groups with different conducting voltage drops can be controlled to be lighted at different stages of a pulsating cycle corresponding to different values of the pulsating direct current voltage vrec (t), so as to improve the efficiency of the light-emitting load, which can be seen in table 2 in other embodiments. But when switching between different LED array combinations, a (low frequency) strobe will result.

As shown in fig. 48, after studying the reason for the strobe, the inventors proposed several concepts of overcoming/reducing the strobe, wherein one of the concepts is to turn on the LED arrays of N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 and LED _ N5 according to the minimum value of the pulsating direct-current voltage vrec (t) in the pulsating period instead of switching on the LED arrays of different groups according to the fluctuation of the pulsating direct-current voltage vrec (t). For example, if the minimum value of the pulsating dc voltage vrec (t) is lower than the full bright threshold ALL _ ON and higher than the ON-voltage drops of the LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N4 and higher than the ON-voltage drops of the LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5, only the LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N4 or the LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5 are turned ON during the full pulse period. Even if the pulsating dc voltage vrec (t) rises back to the maximum value and its neighborhood enough to turn on all N LED arrays, the same part of the N LED arrays, such as LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4, or LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5, remains on.

Of course, for convenience of explanation, it is assumed that the LED array LED _ N5 and the LED array LED _ N4 have the same turn-on voltage drop, that is, the first partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 and the second partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 have the same turn-on voltage drop. Further alternatively, only the first part of the LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4 may be turned on, and the second part of the LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N5 may be turned off, during the full pulsing period. The first partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 and the second partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 may also be alternately turned on at a first predetermined frequency in the pulsing period. Since the first predetermined frequency can be generated by a timer and set to be higher than the power frequency, the frequency change does not cause the low-frequency strobe, but causes other beneficial effects, which can be seen in the related embodiments and will not be described herein.

Continuing with fig. 48, the horizontal axis is the time axis and the vertical axis vrec (t) corresponds to the rectified pulsating dc voltage; the vertical axis ALL _ ON corresponds to the sum of conduction voltage drops when the LED _ N1, the LED _ N2, the LED _ N3, the LED _ N4 and the LED _ N5 are ALL turned ON, that is, the full-bright threshold; the vertical axis IB1(T) corresponds to the current when the first partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N4 are individually turned on; the vertical axis IB2(T) corresponds to the current when the second partial LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 are individually turned on; the vertical axis ib (t) corresponds to the current when all of the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 are turned on, wherein the width of each shaded portion along the vertical axis represents the time of operating the first part of LED array and/or the second part of LED array in the corresponding pulse period. For convenience of explanation, in this embodiment, it is assumed that the conduction voltage drops of the first part LED array and the second part LED array are the same.

In addition, the pulsating dc voltage vrec (t) comes from the mains, which varies between a higher level and a lower level, but the frequency of this variation is not high and the holding time at both the high and the low level is relatively long, for example 1-2 hours. The aforementioned pulsating direct current voltage vrec (t) cannot turn on all the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 at the minimum value in the pulsating period, and generally occurs when the pulsating direct current voltage decreases to a lower level along with the fluctuation of the utility power. If the utility power is increased back to a higher level, the pulsating dc voltage vrec (t) also has a higher level as a whole, and at this time, the pulsating dc voltage vrec (t) may also turn on all the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 at the minimum value in the pulsation period. In the case of such a high pulsating direct current voltage vrec (t), the state in which all of the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 are lit can be restored without turning on only a part thereof. However, for the process of switching between N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5 and partial LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, such sudden complete interchange/switching, if not controlled by a control unit (e.g. with an integrator), but relying only on the response of a simple circuit to a change in dc voltage, for example: the minimum value of the pulsating direct current voltage vrec (t) detected in the previous period is higher than the full bright threshold ALL _ ON, and then the light is suddenly changed from the state where the first part of the LED arrays are turned ON to the state where the n LED arrays are turned ON ALL in the next period.

In this regard, another concept proposed by the inventors for at least the purpose of reducing stroboflash is: the conversion process between part of the LED arrays and all n LED arrays is actively controlled by a control unit comprising an integrator and other modules, so that the process is gradually performed and gradually completed in a plurality of pulse periods, and is not completed in the front pulse period and the back pulse period which are adjacent to each other or in the same pulse period. This further avoids strobing during switching between the n LED arrays and the partial LED arrays.

As described above, the inventors propose several technical ideas for one aspect of the present invention: and gradually switching between the n LED arrays and partial LED arrays, locking and lighting partial LED arrays at a low-voltage level instead of alternately conducting a plurality of partial/subset LED arrays in the n LED arrays at a full low-voltage level. Here, it should be noted that: these concepts may each be applied independently to methods of some embodiments of the invention or implemented in apparatus of some embodiments of the invention. In some embodiments of the invention, combinations of these concepts will be described as examples, in order to provide a simplified and representative description.

In the method according to another embodiment of the present invention, it is further proposed that the LED array control method includes steps SA-1) and SA-2), in step SA-1), when the minimum value of the pulsating direct current voltage vrec (T) is higher than the full lighting threshold ALL _ ON enough to turn ON n LED arrays, for example, between T003 and T004 in fig. 48, the n LED arrays are driven to be fully lit. In step SA-2) of the method of the present embodiment, in response to the pulsating direct current voltage vrec (t) being lower than the full lighting threshold ALL _ ON, only a part of the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, and LED _ N5 (hereinafter, referred to as LED _ N1-5) are driven to be lit.

Optionally, in some embodiments of the present invention, the dc power supply outputs a rectified pulsating dc voltage, and step SA-2) further comprises step SA-2-NO): in response to the lowest value of the pulsating direct current voltage vrec (t) falling below the full light threshold ALL _ ON, only a portion of the n LED arrays are driven to be lit during each of at least one pulsating cycle of the pulsating direct current voltage vrec (t).

Optionally, in some embodiments of the present invention, the partial LED array is a first partial LED array LED _ N1, LED _ N2, LED _ N3, and LED _ N4 (hereinafter referred to as LED _ N1-4) in the N LED arrays, and may be turned on/lit by the minimum voltage of the pulsating dc voltage vrec (t) in each pulse period.

Optionally, in some embodiments of the present invention, the partial LED array is a plurality of partial LED arrays in the N LED arrays LED _ N1-5, and can be turned on/lit by the minimum voltage of the pulsating dc voltage vrec (t) in each pulse period.

Optionally, in some embodiments of the present invention, the first LED array LED _ N1-4 has the maximum or next largest number of N LED arrays LED _ N1-5 that can be turned on by the lowest voltage in the pulsating period of the pulsating DC voltage VREC (T). Alternatively, each of the plurality of partial LED arrays has the maximum or next largest number of N LED arrays LED _ N1-5 that can be turned on by the lowest voltage in the pulsating period of the pulsating dc voltage vrec (t).

Specifically, in step SA-2-NO), in response to the lowest value of the pulsating direct current voltage vrec (t) falling below the full lighting threshold ALL _ ON, within each of the at least one pulsating period (or across one or more of the at least one pulsating period), actively controlling to cyclically turn ON/light ON a plurality of LED arrays of the first part LED array LED _ N1-4, the second part LED array, and so ON, of the N LED arrays at a first predetermined frequency. Alternatively, in step SA-2-NO), a first subset of LED arrays LED _ N1-4 of the N LED arrays are actively controlled to be turned ON/illuminated individually within each of the at least one pulsing period (or across one or more of the at least one pulsing period) in response to the lowest value of the pulsating direct current voltage vrec (t) falling below the full light threshold ALL _ ON. Since the two manners of "the first part LED array is lit individually" and "the plurality of parts of LED arrays are lit cyclically" in step SA-2-NO) are similar, and for brevity, in some related embodiments, only "the plurality of parts of LED arrays are lit cyclically in each pulse cycle" is taken as an example, but it is not excluded that "only the first part of LED arrays are lit in each pulse cycle" also belongs to another aspect of the present invention.

More preferably, in step SA-2), one or more of the first part LED array LED _ N1-4, for example LED _ N4, and the second part LED array of the N LED array LED _ N1-5, for example LED _ N5, may also be actively controlled to be alternately or alternately turned on/on at a first predetermined frequency (e.g. 40kHz, etc.) far above the power frequency, where it should be understood that: with these steps and embodiments thereof, only a portion, but not all, of the N array LEDs _ N1-5 are lit at any time/at any one time during the pulsing cycle of the low voltage horizontal dc power supply. In this way, the state in which the first partial LED array LED _ N1-4 is lit during the pulse cycle is locked, and switching of the LED arrays does not occur at a low frequency with the pulse cycle, that is, switching from the state in which the first partial LED array LED _ N1-4 is lit to the state in which all of the N LED arrays LED _ N1-5 are lit is (passively) switched back again as the value of the dc voltage does not rise from below the full-on threshold to above the full-on threshold. Of course, as the pulsating dc voltage vrec (t) continues to fluctuate to a lower level and is insufficient to turn on the first part LED array LED _ N1-4 at the minimum value of the pulsating dc voltage vrec (t), the first part LED array LED _ N1-4 may be turned on to a LED array combination corresponding to the lower pulsating dc voltage vrec (t) level, such as the fourth part LED array LED _ N1, LED _ N2, LED _ N3, the fifth part LED array LED _ N1, LED _ N2, and LED _ N4. If the pulsating direct voltage vrec (t) is kept constant at this level (e.g. its effective value or average value is constant), only the LED array combination with the lowest conduction voltage drop corresponding to this pulsating direct voltage vrec (t), e.g. one of the fourth part LED array LED _ N1, LED _ N2, LED _ N3, fifth part LED array LED _ N1, LED _ N2, LED _ N4, or the fourth part LED array LED _ N1, LED _ N2, LED _ N3, and fifth part LED array LED _ N1, LED _ N2, LED _ N4, is turned on alternately at the above-mentioned first predetermined frequency higher than the power frequency, in the corresponding pulsating cycle, either at the peak or at the trough, whereby the effective value of the minimum value of the pulsating direct voltage vrec (t) that can be turned on is locked, the stroboscopic in the process that the n LED arrays switch to light different LED arrays with larger difference of conduction voltage drop along with the fluctuation of the pulsating direct current voltage VREC (T) is reduced.

Of course, from another perspective: in the first and second partial LED arrays LED _ N1-4 and LED _ N1, LED _ N2, LED _ N3, and LED _ N5, the LED arrays LED _ N1, LED _ N2, and LED _ N3 may be regarded as being kept in a normally-on state while high-frequency rotation occurs only between the LED arrays LED _ N4 and LED array LED _ N5. Optionally, LED array LED _ N4 and LED array LED _ N5 have the same turn-on voltage drop.

Where the number of LED arrays in the first portion of LED arrays is 4, optionally the first portion of LED arrays LED _ N1-4 may be selectively (dynamically) configured from the N LEDs, such that this number 4, is also the maximum or next largest number that the pulsating direct voltage vrec (t) can conduct in the N LED arrays LED _ N1-5 at its lowest value. This allows for adaptation (adaptation for) of the dc voltage with maximum efficiency, full utilization of the dc voltage, and a larger light emitting area for the n LED arrays at a lower level of pulsating dc voltage vrec (t).

Preferably, the joint set of the plurality of parts of the LED array that are rotated, for example, the first part LED array LED _ N1-4, the second part LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 covers all 5 or 4 of the N LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N4, LED _ N5. Furthermore, all the n or n-1 arrays are in a state of being actively and alternately lighted at the first predetermined frequency or in a normally lighted state, so that under the visual angle of observation of a user, the luminous effect and the stroboscopic performance are equivalent to those of the n LED arrays which are all turned on, and although only 4 LED arrays are turned on at each instant, the whole luminous area of the n LED arrays is kept unchanged, and the n LED arrays are influenced by the fluctuation of the pulsating direct current voltage vrec (t) wholly or locally.

Preferably, a step of switching/converting/transitioning between the n LED arrays and the partial LED arrays is further included between the steps SA-1) and SA-2). In some embodiments of the present invention, the switching process allocation between "N LED arrays LED _ N1-5 are all lit" and "LED arrays LED _ N1-4 and LED arrays LED _ N1, LED _ N2, LED _ N3, LED _ N5 are alternately lit" is done stepwise/gradually over a plurality of pulsing periods. Specifically, for the above-mentioned switching process from "n LED arrays are all lit" to "partial LED arrays are lit alternately" or from "partial LED arrays are lit alternately" to "n LED arrays are lit entirely", the method of the related embodiment may further include a step of gradually adjusting (e.g., incrementally or decreasingly) the relative ratio between the duration of "partial LED arrays are lit alternately" and the duration of "n LED arrays are lit entirely" through a plurality of consecutive pulsation cycles, or gradually adjusting the duty ratio/value/average value of the current corresponding to "partial LED arrays are lit alternately" and the current corresponding to "n LED arrays are lit entirely" in each pulsation cycle, for example, one is gradually increased and the other is gradually decreased.

Generally, in some commercial power application scenarios, the dc voltage is a pulsating dc voltage vrec (t) output after rectifying a commercial power input, and the fluctuation of the commercial power is generally regular, rather than completely random and disordered, for example, although the commercial power varies between a higher level and a lower level, the frequency of the variation is not high, and the holding time at the high level and the low level is relatively long, for example, 1 hour. Sometimes, the dc voltage, although overall at a low level, has a maximum value in its pulse period that is still greater than the full lighting threshold, i.e. sufficient to light all n LED arrays. The method of some embodiments of the invention will be further described herein, taking this case as an example, but it should be understood that: the method of the related embodiment of the present invention is not limited to such a fluctuation of the dc voltage with respect to the full bright threshold, but is also applicable to a case where the dc voltage is decreased to a lower level, for example, the maximum value of the dc voltage in the ripple period thereof is also decreased below the full bright threshold (not shown in the figure), i.e., the dc voltage fluctuates with respect to other lower voltage thresholds or spans a lower voltage interval. The applicant reserves the right to carry out divisional, continuation, and partial continuation applications of these more various modifications.

As described above, the maximum value and a certain neighborhood of the pulsating direct current voltage vrec (t) in the pulsating period thereof are still greater than the full lighting threshold ALL _ ON, and therefore, in the process of switching between the two states of "ALL lighting of the n LED arrays" and "partial lighting of the LED arrays by turns", ALL the n LED arrays are lighted by the pulsating direct current voltage vrec (t) greater than the full lighting threshold ALL _ ON in a plurality of pulsating periods (for example, the greater direct current voltage may be located in the neighborhood of the maximum value of each pulsating period); and alternately lighting part of the LED arrays at the time except for lighting all the n LED arrays. And i) the duty ratio/value/average value of the current for lighting part of the LED arrays in each of the plurality of pulse periods is reduced in a coordinated and rotating manner, and the duty ratio/value/average value of the current for lighting all the n LED arrays in each of the plurality of pulse periods is increased synchronously; or ii) the duty ratio/value/average value of the current for lighting part of the LED arrays in each plurality of pulse periods is increased in coordination with the rotation, and the duty ratio/value/average value of the current for lighting all the n LED arrays in each plurality of pulse periods is decreased synchronously. Alternatively, the method in some embodiments of the invention may further comprise the step of: a) in a plurality of pulse periods, the duty ratio/average value/amplitude of current pulses for lighting part of the LED arrays are reduced in a coordinated and rotating manner, and the duty ratio/average value/amplitude of current pulses for lighting all n LED arrays are increased synchronously; or b) coordinating the increasing of the duty ratio/average value/amplitude of the current pulse for alternately lighting part of the LED arrays in a plurality of pulse periods, and synchronously, decreasing the duty ratio/average value/amplitude of the current pulse for lighting all the n LED arrays.

Referring to fig. 48, before time T001, the minimum value of the pulsating direct current voltage vrec (T) is greater than the full bright threshold ALL _ ON.

At the time T001, the minimum value of the pulsating direct current voltage vrec (T) is smaller than the full lighting threshold ALL _ ON, and the self-operation is "N LED arrays LED _ N1-5 are ALL lit", the self-operation is gradually switched and operated "LED arrays LED _ N1-4 and LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5 are alternately lit", specifically, the switching process is gradually/gradually completed in a plurality of pulsation cycles until the time T002, and the self-operation is completely switched and lit by "LED arrays LED _ N1-4 and LED arrays LED _ N1, LED _ N2, LED _ N3, and LED _ N5".

In the time interval between T002-1 and T003-1, the minimum value of the pulsating direct current voltage VREC (T) is smaller than the full-bright threshold ALL _ ON, and the LED array LED _ N1-4 and the LED arrays LED _ N1, LED _ N2, LED _ N3 and LED _ N5 are continuously operated to be lighted by turns.

In at least one pulsating cycle before the time T003, the minimum values of the pulsating direct-current voltage vrec (T) are ALL greater than the full lighting threshold ALL _ ON, and the switching operation is gradually switched from the operating state of "LED array LED _ N1-4 and LED array LED _ N1, LED _ N2, LED _ N3, LED _ N5 are alternately lit" or "LED array LED _ N4 and LED array LED _ N5 are alternately lit", to "N LED arrays LED _ N1-5 are ALL lit", specifically, the switching process is allocated to be gradually/gradually completed in a plurality of pulsating cycles, and continues to be operated at "N LED arrays LED _ N1-5 are ALL lit" until the time T004.

After time T004, the LED array is continuously operated, namely, N LED arrays LED _ N1-5 are all lightened "

Alternatively, as shown in fig. 48, I) the current pulses for alternately lighting the first part LED array LED _ N1-4, the second part LED array LED _ N1, LED _ N2, LED _ N3 and LED _ N5, i.e., IB1(T) and IB2(T), and ii) the current pulses for lighting all N LED arrays (in a plurality of continuous pulsation cycles, i.e., IB (T)), are complementary in time domain, so that the N LED arrays have only the above two mutually switched states, and there is no all extinguished state and thus stroboscopic effect.

With continued reference to fig. 48, the at least one pulse cycle referred to above may be understood as the pulse cycle encompassed between time T002 and time T003. The plurality of pulse cycles mentioned above may be understood as a pulse cycle included from time T001 to time T002, or from time T003 to time T004.

It should be understood that: the components, units, and modules in the driving circuit/apparatus and the lighting circuit/apparatus may be implemented as corresponding entity apparatuses by hardware such as a comparator, an integrator, a timer, a delay circuit, and a trigger, and may also be understood as functional modules that are necessary to implement the steps of the related program flow or the steps of the method. Therefore, in some embodiments of the present invention, the method may be implemented mainly by a computer program/method described in the specification, and in other embodiments, the method may be implemented as a related entity apparatus by hardware.

In addition to several embodiments of the driving method of a lighting load provided for the present application, the present application also provides embodiments of a driving/controlling device of a lighting load based on the same/similar ideas. The driving/controlling device of the light emitting load in the embodiments includes one or more physical or virtual devices/modules, each operable to run steps and sub-steps of the driving method of the light emitting load in some corresponding embodiments. For example, fig. 36a and 36b are functional block diagrams of two hardware circuits of a driving circuit/a lighting device according to another embodiment of the present invention. The driving circuit/lighting device 115 shown in fig. 36a includes a full LED lighting unit 1151 and a partial LED cutoff unit 1152. The driving circuit/lighting device 215 shown in fig. 36b includes a voltage detecting unit 2152 and an LED selective turn-on unit 2151.

An all-LED lighting unit 1151 operable to drive the n LED arrays to be all lit when the voltage of the dc power supply Volt _1 is higher than the all-on threshold value enough to turn on the n LED arrays;

and a partial LED turn-off unit 1152 operable to drive the n LED arrays to be partially lit when the voltage of the dc power supply Volt _1 is lower than a full-on threshold value and is insufficient to turn on the n LED arrays.

A voltage detection unit 2152 operable to detect a voltage of the dc power supply Volt _ 1; the voltage of the direct current power supply higher than the full-brightness threshold is enough to conduct n LED arrays n _ LED, and the voltage of the direct current power supply lower than the full-brightness threshold is not enough to conduct all n LED arrays n _ LED;

the LED selection on unit 2151 is operable to light up some or all of the n LED arrays in response to/as the voltage of the dc power supply varies with respect to a full lighting threshold, in other words, to drive the n LED arrays to be fully lit up when the voltage of the dc power supply Volt _1 is higher than the full lighting threshold, and to drive the n LED arrays to be partially lit up and to be extinguished when the voltage of the dc power supply Volt _1 is lower than the full lighting threshold.

Of course, the present invention is not limited to the circuit configurations shown in fig. 36a/b, and other variations of the related circuit configurations are also disclosed in other embodiments of the present invention. And the circuit functional block diagram shown in fig. 36a/b may also include other modules/sub-modules configured/operable to perform the control method/control method of some embodiments of the present invention or corresponding steps, sub-steps therein.

The physical modules in the driving circuit/lighting device may be implemented by a hardware circuit structure, or may be implemented by one or more software programs executable by a processor. The circuit modules or the program modules may correspond to the driving methods of the light emitting loads according to several embodiments of the present invention, and are not described herein again.

In another embodiment of the present invention, there is also provided a lighting device including a control unit configured to perform the driving method/control method, etc. of any of the embodiments of the present invention, or some steps, sub-steps of the method.

In another embodiment of the present invention, there is also provided a driving circuit or a control circuit, including a control unit configured to execute methods such as the driving method/control method of any embodiment of the present invention, or some steps and sub-steps of the methods.

In the control method/driving method of the above embodiments, a control method/driving method implemented based on the driving circuit and the control circuit of some other embodiments of the present application is described, which is a control method/driving method independent of a specific circuit configuration. Although some explanations are made in the driving method of the embodiment of the present invention in conjunction with the driving circuit, the control circuit and the related electrical signal waveform diagrams of other embodiments of the present application, it should be clear to those skilled in the art that this does not constitute a limitation to the present invention, nor does the specific circuit structure constitute a limitation to the application and implementation of the method in the embodiment. Furthermore, it should be clear to those skilled in the art that the driving circuit and the control circuit modified according to the technical idea of the driving/control circuit according to some embodiments of the present application may still be used to implement the control/driving method according to some embodiments of the present invention, so that the present invention is intended to include the related control/driving method and all hardware circuits or software programs capable of implementing such method, and the media or electronic devices storing such software programs, etc., and the protection scope of the present invention should be defined by the appended claims.

Alternative embodiments

The present invention also provides a number of alternative embodiments in order to facilitate a person skilled in the art to fully appreciate the spirit of the present invention.

1. A control circuit is used for controlling an electric loop comprising n LED groups and a direct current power supply which are connected in series, and is characterized by comprising a control unit and m branch switch units; n is greater than or equal to 2, m is greater than or equal to 1, m is less than or equal to n, and m and n are integers;

when the output voltage of the direct current power supply is smaller than the sum of the conducting voltage drops of the n LED groups, the control unit conducts at least one sub-switch unit and cuts off the rest sub-switch units to form a sub-loop comprising the conducted at least one sub-switch unit, the conducted LED groups and the direct current power supply, and the sum of the conducting voltage drops of the conducted LED groups is smaller than the output voltage of the direct current power supply.

2. The control circuit according to alternative embodiment 1, wherein the current flowing through the main loop is a main loop current, the current flowing through the sub loop is a sub loop current, and the control unit controls the sub loop current to be larger than the main loop current.

3. The control circuit according to alternative embodiment 1, wherein the control unit turns on at least one of the sub-switching units and turns off the remaining sub-switching units to form a sub-loop including the turned-on sub-switching unit, the turned-on LED group, and the dc power supply, includes:

when the number of the sub-loops is larger than or equal to two, the control unit controls the control circuit to rotate at least two different sub-loops selected from all the sub-loops at a rotation frequency.

4. The control circuit of alternate embodiment 3 wherein the conducting LED groups in the at least two different subcircuits comprise all n LED groups.

5. The control circuit according to alternative embodiment 3, wherein all the sub-loops are respectively sorted from high to low into a first-level sub-loop, a second-level sub-loop and a higher-level priority sub-loop according to the proximity degree of the sum of the voltage drops of the LED groups which are conducted and the output voltage of the dc power supply;

6. The control circuit according to alternative embodiment 1, wherein the m sub-switching units are respectively connected in parallel to two ends of the corresponding m LED groups.

7. The control circuit of alternate embodiment 6 wherein the control circuit further includes at least one current limiting device connected in series on the electrical circuit; the impedance of the current limiting device sets a main loop current flowing through the main loop and a sub loop current flowing through the sub loop.

8. The control circuit of alternative embodiment 1, further comprising at least one current limiting device connected in series with the electrical circuit; the impedance of the current limiting device sets the main loop current flowing through the main loop.

9. The control circuit of alternative embodiment 8, wherein the current limiting device, at least one LED group adjacent to the current limiting device, form at least one series branch; x of the m sub-switch units are respectively connected in parallel at two ends of the serial branch, and the other m-x sub-switch units are respectively connected in parallel at two ends of the corresponding LED group; x is greater than or equal to 1 and less than or equal to m, x being an integer.

10. The control circuit according to alternative embodiment 9, wherein when at least one of the x sub-switching units connected in parallel to both ends of the serial branch is turned on, the control unit sets a sub-loop current flowing through the sub-loop by controlling on-resistance of the turned-on sub-switching unit;

if the x branch switch units connected in parallel at the two ends of the serial branch circuit are all cut off, the impedance of the current limiting device sets the branch circuit current flowing through the branch circuit.

11. The control circuit according to alternative embodiment 2, wherein the control unit controls the sub-loop current and/or the main loop current such that a variation range of the output power of the dc power supply does not exceed a first preset threshold;

and/or the presence of a gas in the gas,

12. The control circuit of alternate embodiment 7 or 8 wherein the current limiting device includes at least one resistor.

13. The control circuit of alternative embodiment 7 or 8, wherein the current limiting device comprises a fet and/or a transistor, and wherein the impedance of the current limiting device is controlled by the control unit to control the conduction level of the fet and/or the transistor.

14. The control circuit of alternative embodiment 1, wherein the sub-switching unit includes a field effect transistor and/or a triode.

15. The control circuit according to alternative embodiment 3, wherein, when the dc power supply is a pulsating dc power supply, the rotation frequency is greater than a pulsating frequency of a pulsating dc voltage output from the pulsating dc power supply.

16. The control circuit of any of alternative embodiments 1-11, 14, 15, wherein at least a portion of the control circuit is integrated into one or more integrated circuits.

17. A control circuit comprising a control circuit as claimed in any of the alternative embodiments 1 to 16, the control circuit further comprising an electrical circuit comprising a dc power supply and n LED groups connected in series.

18. The control circuit of alternative embodiment 17 wherein the dc power supply comprises a constant dc power supply or a pulsating dc power supply.

19. The control circuit of alternative embodiment 18 wherein the pulsating dc power source comprises a rectifier and an energy storage capacitor, the rectifier having an input connected to the ac power and an output connected in parallel to the energy storage capacitor.

20. The control circuit of alternative embodiment 19 wherein at least a portion of the control circuit and at least a portion of the rectifier are integrated in one or more integrated circuits.

21. A control method implemented using the control circuit according to any one of alternative embodiments 17 to 20, characterized by comprising the steps of:

judging the magnitude relation between the output voltage of the direct current power supply and the sum of the conduction voltage drops of the n LED groups;

in response to the output voltage of the direct current power supply being greater than or equal to the sum of the conducting voltage drops of the n LED groups, turning off the m sub-switch units in the control circuit to form a main loop including the n LED groups and the direct current power supply;

in response to the output voltage of the direct current power supply being smaller than the sum of the conducting voltage drops of the n LED groups, conducting at least one sub-switch unit, and cutting off the rest sub-switch units to form a sub-loop comprising the conducted sub-switch units, the conducted LED groups and the direct current power supply; and the sum of the voltage drops of the conducted LED groups is less than the output voltage of the direct current power supply.

22. The control method of alternative embodiment 21 wherein the current flowing through the main loop is a main loop current and the current flowing through the sub loop is a sub loop current, the sub loop current being greater than the main loop current.

23. The control method of alternative embodiment 21, wherein the turning on at least one of the sub-switching units and turning off the remaining sub-switching units to form a sub-loop including the turned-on sub-switching unit, the turned-on LED group, and the dc power supply includes:

and when the number of the sub-loops is greater than or equal to two, controlling the control circuit to rotate at least two different sub-loops selected from all the sub-loops at a rotation frequency.

24. The control method of alternative embodiment 23 wherein the LED groups that are on in the at least two different subcircuits include all n LED groups.

25. The control method according to alternative embodiment 23, wherein all the sub-loops are prioritized into a first-level sub-loop, a second-level sub-loop and a higher-level sub-loop according to the proximity of the sum of the voltage drops of the LED groups to the output voltage of the dc power supply from high to low; the at least two different sub-loops include at least a first level priority sub-loop and a second level priority sub-loop.

26. The control method according to alternative embodiment 21, wherein when the m sub-switching units are respectively connected in parallel to two ends of the corresponding m LED groups and the electrical circuit is further connected in series to at least one current limiting device:

27. The control method of alternative embodiment 21, wherein the electrical circuit is further connected in series with at least one current limiting device, the current limiting device, at least one LED group adjacent to the current limiting device, forming at least one series branch; the control method sets a main loop current flowing through the main loop through the impedance of the current limiting device.

28. The control method according to alternative embodiment 27, wherein when x of the m sub-switch units are respectively connected in parallel to two ends of the serial branch, and the remaining m-x sub-switch units are respectively connected in parallel to two ends of the corresponding LED group:

the control method also comprises the steps that when at least one of the x sub-switch units connected to two ends of the serial branch in parallel is conducted, sub-loop current flowing through the sub-loop is set by controlling the conducting impedance of the conducted sub-switch unit;

the control method also sets sub-loop current flowing through the sub-loop through the impedance of the current limiting device when x sub-switch units connected to two ends of the serial branch in parallel are all cut off;

29. The control method of alternative embodiment 21, wherein the sub-loop current and/or the main loop current are controlled such that the output power of the dc power supply does not vary beyond a first preset threshold;

and/or the presence of a gas in the gas,

30. The control method according to alternative embodiment 23, wherein, when the dc power supply is a pulsating dc power supply, the rotational frequency is greater than a pulsating frequency of a pulsating dc voltage output from the pulsating dc power supply.

31. The method of any of alternative embodiments 26-28, wherein when the current limiting device comprises a fet and/or a transistor, the impedance of the current limiting device is controlled by controlling a degree of conduction of the fet and/or transistor.

32. A lighting device fabricated using the control circuit of any one of alternative embodiments 17-20. 33. A control circuit for driving an array of n LEDs at least partially connected in series and powered by a DC power source,

The control circuit includes:

a control unit;

m switching units configured to respectively correspondingly couple m of the n LED arrays when the control circuit is driven/applied to the n LED arrays, respective control terminals of the m switching units being respectively connected to the control unit, controlled by the control unit to bypass the corresponding LED arrays;

34. The control circuit of alternate embodiment 33 wherein the m switch units bypass the corresponding one or more LED arrays by being controlled by selective conduction by the control unit.

35. The control circuit of alternate embodiment 34 wherein x of the m switch units are correspondingly connected in parallel with x of the m LED arrays, the remaining m-x switch units are respectively correspondingly connected across one end of the remaining m-x LED arrays and the DC power output, the m-x switch units are respectively operable/conductible to allow the DC power to be looped back from the corresponding end of each of the m-x LED arrays, wherein x is an integer, m ≧ 2, m ≧ x ≧ 0.

36. The control circuit of alternate embodiment 34 further comprising a current limiting device connected in the control circuit to form a series circuit with the n LED arrays and the dc power source when the control circuit drives the n LED arrays.

37. The control circuit of alternate embodiment 35 wherein the current limiting device and at least a portion of the m switching cells are configured to independently or jointly regulate current flowing through at least a portion of the n LED arrays. 38. The control circuit of alternate embodiment 37 wherein the current limiting device has a control terminal connected to the control unit, the current limiting device and/or at least a portion of the m switching units operable to regulate respective currents in accordance with control signals at the respective control terminals.

39. The control circuit of alternative embodiment 37, wherein the m switching units are N-type devices, and the LED arrays and the current limiting devices that correspond to/are coupled to the m switching units are sequentially disposed along a current direction, wherein two ends of x switching units are connected to an upstream of the current limiting device, and two ends of the remaining m-x switching units are respectively connected to an upstream and a downstream of the current limiting device, wherein x is an integer, m ≧ 2, and m ≧ x ≧ 0.

The control circuit of alternate embodiment 37, wherein the m switching units are P-type devices, the current limiting device and the LED array corresponding to/coupled to the m switching units are sequentially disposed along the current direction, wherein two ends of x switching units are connected to the downstream of the current limiting device, two ends of the remaining m-x switching units are respectively connected to the upstream and downstream of the current limiting device, wherein x is an integer, m is greater than or equal to 2, and m is greater than or equal to x is greater than or equal to 0.

41. The control circuit of alternative embodiment 39 wherein the m switching units are each controlled by the control unit to switch between at least an on, or an off state.

42. The control circuit of alternative embodiment 41 wherein the m switching cells are N-type devices and the current input/anodes of the m-x LED arrays are each coupled to the negative terminal of the DC power supply via a corresponding switching cell; or

The m switch units are P-type devices, and the current output ends/cathodes of the m-x LED arrays are respectively coupled to the positive polarity end of the direct current power supply through the corresponding switch units.

43. The control circuit of alternative embodiment 42 wherein the m switching cells are N-type devices and at least a portion of the x switching cells and the m-x switching cells are serially connected in series in the direction of current flow.

44. The control circuit of alternate embodiment 43 wherein 2 ≧ m ≧ 1, n ≧ 2; the control circuit includes:

a first pin configured to couple out the positive polarity output terminal of the DC power source,

a second pin configured to couple a negative polarity end of a first LED array and a positive polarity end of a second LED array of the n LED arrays to the outside;

A third pin configured to couple a negative polarity end of a second LED array of the n LED arrays externally;

a fourth pin configured to couple a negative polarity output terminal of the DC power supply to the outside; and the number of the first and second groups,

a positive polarity terminal of a first switch cell of the m switch cells is connected to the second pin, and a negative polarity terminal of the first switch cell is coupled to the fourth pin.

45. The control circuit of alternate embodiment 44 wherein a positive polarity terminal of the current limiting device is connected to the third pin; its negative polarity end is connected to the fourth pin, an

The negative polarity terminal of the first switching unit is directly connected to the fourth pin, or is connected to the third pin and coupled to the fourth pin through the current limiting device.

46. The control circuit of alternate embodiment 45 wherein a positive polarity terminal of a second switch cell of the m switch cells is connected to the first pin; the negative polarity terminal of the second switching unit is connected to the second pin.

47. The control circuit of alternate embodiment 46 comprising: a first carrier and a second carrier isolated from each other, the second carrier configured to carry the second switching unit, the first carrier configured to carry the first switching unit.

48. The control circuit of alternate embodiment 47 wherein the current limiting device and at least a portion of the controller are disposed on the first carrier.

49. The control circuit of alternate embodiment 44 further comprising a current programming interface disposed in the first switching unit or the current limiting device configured to receive a first resistor connected in series from a periphery to set a current of a conducting one of the n LED arrays.

50. The control circuit of any of alternative embodiments 33-49 wherein the DC power source outputs a pulsating DC voltage; the control unit is configured to: adjusting the current in the at least one switching unit that is turned on to vary in a reverse direction to the pulsating direct current voltage/the voltage experienced by the n LED arrays.

51. The control circuit as in alternative embodiment 50, the control unit further configured to: reducing the current in the turned-on LED array of the n LED arrays as the pulsating direct current voltage/the voltage sustained by the n LED arrays increases, or increasing the current in the turned-on LED array of the n LED arrays as the pulsating direct current voltage/the voltage sustained by the n LED arrays decreases;

Thus, adjusting the power of the n LED arrays remains within a neighborhood of the first power value.

52. The control circuit as in alternative embodiment 51, wherein the control unit comprises an electrical signal measurement unit coupled to the control circuit to obtain a first electrical signal that reflects/represents the pulsating direct current voltage or the voltage sustained by the n LED arrays or has a positive/negative correlation with the pulsating direct current voltage or the voltage sustained by the n LED arrays; and the number of the first and second groups,

the control unit is further configured to: 1) in response to the first electrical signal being less than a first threshold, controlling at least one of the M switching units to conduct to establish a bypass; 2) controlling all of the M switch units to be turned off in response to the first electric signal being greater than or equal to the first threshold; or

i) In response to the first electrical signal being greater than a first threshold, controlling at least one of the M switching units to conduct to establish a bypass; ii) in response to the first electrical signal being less than or equal to the first threshold, controlling all of the M switching units to be off.

53. The control circuit of alternate embodiment 52 wherein the first threshold corresponds to one of the following five: i) a value of the first electrical signal reflecting a minimum voltage of a dc power supply sufficient to turn on all of the n LED arrays, ii) a reference voltage value differing from the minimum voltage value by a constant positive value, iii) a voltage value of the dc power supply that can bring a turn-on current/luminous flux of the n LED arrays to a predetermined value; iv) a minimum voltage of the dc power supply sufficient to switch on all of said n LED arrays, v) a value of said first electrical signal reflecting a voltage value of the dc power supply that causes the luminous flux of the LEDs in said n LED arrays to reach a predetermined value; VI) a value of a first electrical signal reflecting a minimum voltage of the dc power supply when a luminous flux generated by the voltage/current/power across the n LED arrays reaches a predetermined value; VII) just enough dc voltage value to turn on all of the n LED arrays. Optionally, when at least one of the n LED arrays is bypassed, the current flowing through the n LED arrays or the current flowing through the bypass loop/sub-loop is adjusted by the control unit to be larger than the current of the main loop when all the n LED arrays are turned on; and

The control unit is further configured to: and adjusting the first bypass current in the at least one switched-on switching unit to be larger than the current value flowing through the n LED arrays when the M switching units are all switched off according to the at least first electric signal, so that the product of the voltage borne by the n LED arrays and the first bypass current is kept in the neighborhood of a first power value.

The control circuit of any of alternative embodiments 33-48 or 50-53 wherein x is 0, the control unit further configured to switch the m switching units to establish and/or cancel a bypass loop in response to fluctuations in the first electrical signal relative to the first threshold.

54. The control circuit of any of alternative embodiments 33-49 or 51-53, wherein m > x ≧ 1, m ≧ 2, the control unit further configured to, a) alternately turn off ones of the m switch units at a first predetermined frequency to alternately turn on corresponding ones of the LED arrays in response to the first electrical signal falling below the first threshold; or, b) in response to the first electrical signal falling below the first threshold, alternately turning on a plurality of switch cells including at least one of the x switch cells and at least one of the m-x switch cells at a first predetermined frequency, thereby establishing a plurality of bypass loops that are alternately turned on; and

The first predetermined frequency is greater than the power frequency or the pulse frequency of the direct current voltage.

55. The control circuit as in alternative embodiment 54, wherein the control unit is further configured to: when the first electrical signal positively correlated with the pulsating direct-current voltage is smaller than the first threshold value, coordinating the currents in the plurality of switching units which are switched so that the power of the n LED arrays is kept basically constant before and after switching and is positioned in the neighborhood of the first power value; or

Coordinating, by the plurality of switching units, currents in the plurality of bypass loops such that power of the LED arrays in the plurality of bypass loops is each maintained within a neighborhood of the first power value.

56. The control circuit of alternate embodiment 55 wherein the plurality of bypass loops includes a first bypass loop and a second bypass loop, the control unit further configured to, if the LED array of the n LED arrays that is in the first bypass loop has a larger turn-on voltage drop than the LED array in the second bypass loop: adjusting the current in the second bypass loop to be larger than the current in the first bypass loop, so that the relative rate of change of the power of the LED array in the second bypass loop and the LED array in the first bypass loop is smaller than a first preset percentage, and the first preset percentage is a value smaller than 2%; or

If the LED array conduction voltage drop in the first bypass loop is substantially equal to the LED array in the second bypass loop, the control unit is further configured to: adjusting the rate of change of the current in the second bypass loop relative to the current in the first bypass loop to be no more than a first predetermined percentage such that the relative rate of change of the power of the LED array in the second bypass loop to the LED array in the first bypass loop is less than the first predetermined percentage, the first predetermined percentage being a value less than 2%; and

the number of the LED arrays in the union of the LED arrays in the first bypass loop and the LED arrays in the second bypass loop is greater than the maximum number of the n LED arrays that can be turned on by the DC power supply when the first electrical signal is smaller than the first threshold.

57. The control circuit of alternate embodiment 53' or 54 wherein the control unit is further configured to: if m > x ≧ 1, coordinating currents in the current limiting device and the plurality of switched switching cells during fluctuation of the first electrical signal with respect to the first threshold value such that power of the n LED arrays is maintained within a neighborhood of the first power value in a state where the plurality of switching cells are all turned off and at least partially turned on; or

And coordinating the current in the current limiting device and the currents in the m switching units during fluctuation of the first electrical signal with respect to the first threshold value, such that the power of the n LED arrays remains in the vicinity of the first power value in a state where the m switching units are all turned off and at least partially turned on, as when x is 0.

58. The control circuit of alternative embodiment 55, wherein the control unit is further configured to: during the transition when the plurality of switching units are switched,

i) synchronously controlling the current in a first part of the switch units in the plurality of switch units to be reduced along with the current in a second part of the switch units in the plurality of switch units, so that the power reduction of the LED arrays corresponding to the first part of the switch units is compensated/offset by the power increase of the LED arrays corresponding to the second part of the switch units; and the number of the first and second groups,

ii) synchronously controlling the current in a first part of the switch units in the plurality of switch units to increase along with the decrease of the current in a second part of the switch units in the plurality of switch units, so that the power reduction of the LED arrays corresponding to the second part of the switch units is compensated/offset by the power increase of the LED arrays corresponding to the first part of the switch units.

59. The control circuit of alternative embodiment 56, wherein the control unit is further configured to: during the transition in switching between the first and second bypass loops, i) synchronously controlling the current in the first bypass loop to decrease with increasing second bypass loop current such that the power drop of the LED array in the first bypass loop is compensated/offset by the power increase of the LED array in the second bypass loop; and the number of the first and second groups,

ii) synchronously controlling the current in the first bypass loop to increase as the current in the second bypass loop decreases such that the power drop of the LED array in the second bypass loop is compensated/offset by the power increase of the LED array in the first bypass loop.

60. The control circuit of alternative embodiment 58, wherein the control unit is further configured to: in the transition process of switching conduction from the second part of switch units to the first part of switch units, controlling the current in the first part of switch units to increase synchronously before the descending amplitude of the current in the second part of switch units relative to the descending amplitude before the transition process begins exceeds a preset amplitude value; and/or in the transition process of switching conduction from the first part of switch units to the second part of switch units, controlling the current in the second part of switch units to increase synchronously before the descending amplitude of the current in the first part of switch units relative to the current before the transition process begins exceeds the preset amplitude; wherein the preset amplitude is an arbitrary value smaller than 5%.

61. The control circuit of alternate embodiment 55 wherein the union of the LED arrays in each of the plurality of bypass loops contains or includes all of the n LED arrays; or,

the union of the plurality of LED arrays which are switched on alternately comprises all the n LED arrays; or,

the union of the n-m LED arrays not bypassed and the plurality of LED arrays turned on alternately comprises all of the n LED arrays.

62. The control circuit of alternate embodiment 57 wherein any one of: i) an LED array turned on by each switching group of the switched plurality of switching cells, ii) a union of the n-m LED arrays and the LED array turned on by each switching group of the switched plurality of switching cells, or iii) an LED array in each bypass loop of the plurality of bypass loops, an LED array that can be lit in the n LED arrays corresponding to a maximum or next largest number of outputs of the dc power supply; or

The plurality of switch units or the m switch units are provided with a first switching group, and the n LED arrays can be lighted corresponding to the maximum number or next-largest number of the outputs of the direct current power supply.

63. The control circuit of alternate embodiment 62 wherein the union of the LED arrays in each of the plurality of bypass loops corresponds to all of the n LED arrays; or, the plurality of bypass loops, covering/including all of the n LED arrays; and

the switch unit is a field effect transistor, a triode, a transistor, a power tube or an MOS tube.

63-1. the control circuit of any of the alternative embodiments 33-54, the electrical signal measurement unit coupled to the control circuit to obtain at least one electrical signal reflecting a characteristic of the pulsating direct current voltage;

the electric signal measuring units are respectively coupled to the m switching units; and the number of the first and second groups,

the electric signal measuring unit is configured to judge whether the output voltage of the direct current power supply is enough to turn on the n LED arrays according to the at least one electric signal;

the control unit is configured to selectively turn on the m switch units to keep only a first portion of the LED arrays adapted to the output voltage illuminated in response to the at least one electrical signal reflecting that the output voltage of the dc power supply is insufficient to turn on the n LED arrays.

63-2. the control circuit of alternative embodiment 63-1 wherein the at least one electrical signal, including the second electrical signal, reflects a minimum value of the pulsating direct current voltage or a voltage value of a valley portion; and

the electric signal measuring unit further comprises a second comparator, and output ends of the second comparator are respectively coupled to the m switching units; the second comparator is configured to receive the second electrical signal and a first threshold.

63-3. the control circuit of alternative embodiment 63-2 wherein the dc power supply outputs a pulsed voltage, the control unit configured to, in response to the second electrical signal reflecting that the valley portion of the pulsed voltage is insufficient to turn on the n LED arrays, step by step i) the n LEDs are all turned on through a plurality of pulsed cycles to ii) keep the first portion of the LED arrays fully periodically on.

63-4. the control circuit of alternative embodiment 63-3, wherein the electrical signal measurement unit further comprises an integration unit connected between the second comparator and the m switching units;

the integration unit is operable to coordinate duty cycles of currents in the first part of the LED arrays and duty cycles of currents in the n LED arrays to increase and decrease cycle by cycle respectively in the plurality of ripple cycles according to an output of the second comparator.

63-5. the control circuit of alternative embodiment 63-4, wherein the electrical signal measurement unit further includes a first comparator connected between the integration unit and the m switching units;

the control unit further comprises a signal processing unit through which the first comparators are respectively coupled to the m switching units;

the at least one electrical signal further comprises a first electrical signal reflecting the pulsating direct current voltage or the voltage sustained by the n LED arrays; the first comparator is configured to receive the first electrical signal and an output of the integration unit.

63-6. the control circuit of alternative embodiment 63-5, wherein the signal processing unit includes timing logic circuits respectively coupled to the m switching units, the timing logic circuits configured to: cyclically outputting control signals complementary in time to at least a portion of the m switching cells at a first predetermined frequency in response to the output of the first comparator indicating that the magnitude of the output of the integrating cell is greater than the first electrical signal.

64. The control circuit as in alternate embodiment 62, the control unit further comprising: a timer and a trigger; the electric signal measuring unit, the timer and the trigger are sequentially connected; the output end of the trigger is connected to the control end of at least one of the x switch units;

Wherein the electric signal measuring unit is configured to output a comparison signal to an input terminal of the timer and a control terminal of at least one of the m-x switching units according to a magnitude relationship between the first electric signal and the first threshold.

65. The control circuit as in alternative embodiment 54, the control unit further comprising a timer, an output of the electrical signal measurement unit coupled to an input of the timer, the timer coupled to control terminals of the plurality of switching units, respectively, the electrical signal measurement unit configured to: if it is detected that the first electric signal positively correlated with the pulsating direct current voltage is smaller than the first threshold value, outputting a first comparison signal to the timer, and

the timer is configured to: and responding to the first comparison signal, and controlling/coordinating the alternate conduction of the plurality of switch units or the plurality of bypass loops at the first preset frequency.

66. The control circuit of alternate embodiment 54, the control unit further including timing logic, the output of the electrical signal measurement unit being coupled to the input of the timing logic, the control terminals of each of the plurality of switch units being respectively coupled to the output of the timing logic, thereby outputting a first comparison signal to the timing logic in response to the first electrical signal being less than the first threshold;

The timing logic circuit is configured to cyclically output a plurality of control signals complementary in time at a first predetermined frequency in response to a first comparison signal;

the switch units are respectively controlled by the control signals and are switched on alternately at the first preset frequency;

wherein the first electrical signal is positively correlated with the pulsating direct current voltage.

67. The control circuit of alternate embodiment 66 wherein the control unit further includes a second comparator, an integrating unit, a first comparator connected in series, an output of the first comparator coupled to the control terminals of the plurality of switching units;

the second comparator is configured to receive the second electrical signal and the first threshold and output a comparison result to the integration unit;

the first comparator is configured to compare the first electrical signal with an output of the integrating unit;

the plurality of switching units are controlled by a) the plurality of control signals and b) an output of the first comparator to be i) alternately turned on at the first predetermined frequency or ii) alternately turned on at the first predetermined frequency at a decreasing/increasing duty ratio, respectively;

wherein the second electrical signal reflects a minimum value of the pulsating direct current voltage, the second electrical signal being acquired based on the first electrical signal.

68. The control circuit of any of alternative embodiments 33-49 or 51-54, 55, 56, wherein an input of the electrical signal measurement unit is coupled to the control circuit to obtain at least one electrical signal characterizing the pulsating direct current voltage, and an output of the electrical signal measurement unit is coupled to control terminals of the m switching cells, such that z switching cells of the m switching cells remain on for a full cycle of the pulsating direct current voltage in response to the at least one electrical signal indicating that a minimum value of the pulsating direct current voltage falls below a turn-on threshold.

69. The control circuit of alternate embodiment 68 wherein z of the m switching cells are held on so that the minimum value of the pulsating direct current voltage is sufficient to illuminate q of the n LED arrays, q being the maximum number of LED arrays that the minimum value of the pulsating direct current voltage below the turn-on threshold can illuminate in the n LED arrays; and

when the minimum value of the pulsating direct current voltage is higher than the conduction threshold value, the pulsating direct current voltage is enough to conduct p LED arrays in the n LED arrays in a full period; y of the m switch units are kept on; q is not less than p and not more than n.

The control circuit as in alternative embodiment 69, wherein, when the control circuit is used for the n LED arrays, the positive polarity end of the pulsating direct current voltage, a first LED array of the n LED arrays, and a second LED array are connected in sequence to form the series loop; a second switch unit of the m switch units is connected across: 1) a connection point of the first LED array and the second LED array, and 2) a negative polarity end of the pulsating direct current voltage; thereby, the second switching unit remains on for a full period of the pulsating direct current voltage in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below a conduction threshold.

70. The control circuit of alternate embodiment 69 wherein the control unit further includes an integration unit; the electrical signal measurement unit, the integration unit, and the m switching units are coupled in sequence such that, in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the conduction threshold, the y switching units are kept conductive step by step to the z switching units are kept conductive over a plurality of pulsation cycles.

71. The control circuit of alternate embodiment 70 wherein progressively switching y switch cells to be held on to z switch cells to be held on through a plurality of ripple cycles comprises:

coordinating i) the current or the average thereof in the z switching cells to increment over the plurality of cycles, and ii) the current or the average thereof in the y switching cells to decrement synchronously over the plurality of ripple cycles.

The control circuit of alternate embodiment 71 wherein coordinating i) the current in the z switching cells or the average thereof increases over the plurality of cycles and ii) the current in the y switching cells or the average thereof decreases synchronously over the plurality of ripple cycles further comprises:

within the plurality of ripple periods, the duty cycle/magnitude of the conduction current in the y switch units is adjusted incrementally from cycle to cycle, and, synchronously, the duty cycle/magnitude of the conduction current in the z switch units is adjusted incrementally from cycle to cycle.

The control circuit of any one of alternative embodiments 68-71, wherein the control unit further comprises timing logic circuitry; the electrical signal measurement unit, the timing logic circuit, and the m switch units are sequentially coupled such that, in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the turn-on threshold, the z switch units are selectively turned on among the m switch units by temporally complementary control signals cyclically output by the timing logic circuit at a first predetermined frequency.

73' the control circuit as in alternative embodiment 73, wherein the n LED arrays further comprise a third LED array connected in series in the series loop; the m switching units further include a first switching unit; the first switching unit is to couple the first LED array in parallel when the control circuit is used for the first LED array, the second LED array, and the third LED array; thereby, in response to the at least one electrical signal indicating that the minimum value of the pulsating direct current voltage falls below the turn-on threshold, time-complementary control signals are alternately output by the timing logic circuit to the first and second LED arrays, respectively, at a first predetermined frequency.

74. The control circuit of alternative embodiment 68 wherein the at least one electrical signal comprises a second electrical signal reflecting at least one of i) a maximum value, ii) a minimum value, iii) an average value, or iiii) an effective value of the pulsating direct current voltage; the z switch cells selected at least in part from the x switch cells; and

the z switch cells include at least one of the x switch cells and at least one of the m-x switch cells.

75. The control circuit as in alternative embodiment 54, the control unit further comprising a timer, an output of the electrical signal measurement unit coupled to an input of the timer, the timer coupled to control terminals of the plurality of switching units, respectively, the electrical signal measurement unit configured to: if it is detected that the first electrical signal inversely related to the pulsating direct current voltage is greater than the first threshold value, outputting a first comparison signal to the timer, and

the timer is configured to: and responding to the first comparison signal, controlling/coordinating the rotation turn-off of the plurality of switch units or the plurality of bypass loops at the first preset frequency so as to rotate and turn on the corresponding LED arrays in the n LED arrays.

76. The control circuit of any one of alternative embodiments 65 or 66, the control unit further comprising a flip-flop, an output of the timer being connected to an input of the flip-flop, an output of the flip-flop being connected to a control terminal of the plurality of switching cells.

77. The control circuit as in alternative embodiment 54, wherein the control unit is further configured to:

switching between the series circuit and the plurality of bypass circuits is performed stepwise over successive plural pulsation cycles of the first electric signal in response to a change/rise in the lowest value of the first electric signal with respect to the first threshold; or

Switching between the series loop and the plurality of bypass loops is accomplished in steps through successive multiple pulsing cycles of the first electrical signal in response to a change in a lowest value of the first electrical signal across the first threshold.

78. The control circuit of alternate embodiment 77 wherein the control unit is further configured to:

gradually adjusting, by the plurality of pulsation periods, the relative proportions of i) the duration of the plurality of bypass loops turned on and ii) the duration of the series loop in switching between the series loop and the plurality of bypass loops turned on; or,

in the switching between the series circuit and the alternately conducting bypass circuits, the duty ratio/value/average value of a) the current in the alternately conducting bypass circuits and b) the current in the series circuit in each pulsation period is gradually adjusted.

79. The control circuit of alternate embodiment 78 wherein the first electrical signal is positively correlated with the pulsating direct current voltage; and the control unit is further configured to: turning on the series loop at or near a maximum of the first electrical signal over the plurality of pulse cycles; when the serial loop is cut off, the plurality of bypass loops are switched on alternately; wherein i) the current in the series loop and ii) the current in the plurality of bypass loops are complementary in time domain or pulse shape.

80. The control circuit of alternative embodiment 78, wherein the control unit is further configured to:

i) coordinating the decreasing duty cycle/value/average value of the current in the plurality of bypass loops in each of the plurality of ripple periods, synchronously the increasing duty cycle/value/average value of the current in the series loop in each of the plurality of ripple periods; or

ii) coordinating the increasing duty cycle/value/average value of the current in the plurality of bypass loops in each of the plurality of ripple periods, synchronously the decreasing duty cycle/value/average value of the current in the series loop in each of the plurality of ripple periods; or

iii) coordinating decreasing duty cycle/average/amplitude of current pulses in the plurality of bypass loops over the plurality of ripple periods, synchronously increasing duty cycle/average/amplitude of current pulses in the series loop; or

iiii) coordinating the increasing duty cycle/average/amplitude of the current pulses in the plurality of bypass loops over the plurality of ripple cycles, synchronously the decreasing duty cycle/average/amplitude of the current pulses in the series loop.

81. The control circuit of alternate embodiment 78 wherein the LED arrays in the plurality of bypass loops have or do not have an intersection and have the same turn-on voltage drop.

82. The control circuit of alternate embodiment 81 wherein the plurality of bypass loops are each configured to have a maximum or next-to-maximum amount that the pulsating direct current voltage corresponding to a lowest value of the first electrical signal can conduct in the n LED arrays;

the union set of the LED arrays in the bypass loops switched on alternately covers n or n-1 LED arrays; and

the plurality of pulse cycles include any number of pulse cycles from 3 to 1000, or the plurality of pulse cycles lasts from 1ms to 1000 ms.

83. The control circuit of alternate embodiment 78 wherein the control unit further comprises: a timer and an integration unit coupled to each other;

the control unit is further configured to: adjusting the full bright threshold/first threshold by an integration unit to increment/decrement over the plurality of pulse periods based at least in part on a timing signal from the timer, an

Triggering switching between the series loop and the plurality of bypass loops based at least in part on the increasing/decreasing full bright threshold/first threshold.

84. The control circuit of alternative embodiment 83 wherein the control unit further comprises a comparator coupled to the integration unit; the comparator triggers, in accordance with the input of the integration unit and the first electric signal, i) switching between the series circuit and the plurality of bypass circuits, or, ii) turning on or off of the m-x switching units and the current limiting device.

85. The control circuit of alternate embodiment 77 wherein the control unit is further configured to:

86. The control circuit as in alternative embodiment 53, wherein the control unit is further configured to: switching between the series circuit and the bypass circuit in steps over successive periods of a plurality of pulses of the first electrical signal in response to fluctuations/rises of the lowest value of the first electrical signal relative to the first threshold value; or

Switching between the series loop and the bypass loop is done step by step through successive multiple pulsing cycles of the first electrical signal in response to a change in the lowest value of the first electrical signal across the first threshold.

87. The control circuit of alternative embodiment 86 wherein the control unit is further configured to:

gradually adjusting, by the plurality of pulsation periods, a relative proportion of i) a duration of the bypass loop that is alternately turned on to ii) a duration of the series loop in switching between the series loop and the bypass loop; or,

in the switching between the series circuit and the alternately conducting bypass circuit, the duty cycle/value/average value of a) the current in the alternately conducting bypass circuit and b) the current in the series circuit in each pulse period is gradually adjusted.

88. The control circuit of alternate embodiment 87 wherein the first electrical signal is positively correlated to the pulsating direct current voltage; and the control unit is further configured to: turning on the series loop at or near a maximum of the first electrical signal over the plurality of pulse cycles; when the series circuit is cut off, the bypass circuit is conducted; wherein i) the current in the series loop and ii) the current in the bypass loop are complementary in time domain or pulse shape.

89. The control circuit of alternative embodiment 88 wherein the control unit is further configured to:

i) Coordinating the decreasing duty cycle/value/average value of the current in the bypass loop in each of the plurality of ripple periods, synchronously, the increasing duty cycle/value/average value of the current in the series loop in each of the plurality of ripple periods; or

iii) coordinating the decreasing duty cycle/average/amplitude of the current pulses in the bypass loop with the increasing duty cycle/average/amplitude of the current pulses in the series loop in synchronism over the plurality of ripple periods; or

iiii) coordinating the duty cycle/average/amplitude of the current pulses in the bypass loop to increase incrementally over the plurality of ripple cycles, and synchronously, the duty cycle/average/amplitude of the current pulses in the series loop to decrease incrementally.

90. The control circuit of alternate embodiment 89 wherein the bypass loop is configured to have a maximum or next-to-maximum amount the pulsating dc voltage can conduct in the n LED arrays corresponding to a lowest value of the first electrical signal.

91. A driver circuit comprising the control circuit of any of alternative embodiments 33-49 or 51-53 integrated as a chip or integrated circuit; and, the n LED arrays peripherally coupled to the chip or integrated circuit.

92. The driver circuit of alternate embodiment 91, further comprising the first resistor coupled from the chip or integrated circuit peripheral string to the branch of the first switch cell through the current programming interface.

93. The driver circuit of alternate embodiment 92 further comprising the dc power supply comprising a rectifier circuit configured to receive input power and rectify the input power for output to the n LED arrays; and the number of the first and second groups,

the electric signal measuring unit includes a voltage detecting circuit connected in parallel to an output of the rectifying circuit or the n LED arrays to detect the first electric signal by a corresponding voltage signal; alternatively, the electrical signal measuring unit is connected in series to at least a part of the n LED arrays and/or the m switching units to detect the first electrical signal by a corresponding current signal.

94. The driver circuit of alternate embodiment 91 wherein at least one of the m switching cells and/or the current limiting device is configured as part of a voltage detection circuit.

95. The drive circuit of alternate embodiment 91, wherein the output of the dc power supply is coupled across an electrolytic capacitor.

96. The driver circuit of alternative embodiment 91, wherein n ≧ 2, conduction voltage drops of at least two of the n LED arrays are the same, and conduction can be alternated by corresponding ones of the m switch units.

97. The driver circuit of alternate embodiment 91 wherein at least some of the n-m LED arrays not coupled to the m switching units are connected in series before/upstream of the m LED arrays in the current direction; or

At least part of the n-m LED arrays is connected to the output end of the direct current power supply; or

At least part of the n-m LED arrays are connected with the m LED arrays to keep the normal brightness; or

At least part of the n-m LED arrays are connected in series between at least two of the m LED arrays to keep the constant brightness; or

At least part of the n-m LED arrays are connected in series in a staggered mode in the x LED arrays or between the x LED arrays and the m-x LED arrays so as to keep the normal brightness; or

At least part of the n-m LED arrays cannot be bypassed by the m switch units.

98. The driver circuit as in alternative embodiment 91, wherein the LED arrays that can be bypassed by the first portion of the switching cells and the LED arrays that can be bypassed by the second portion of the switching cells have the same turn-on voltage drop.

99. The driver circuit of alternate embodiment 91 wherein n-m LED arrays not coupled to the m switch cells are connected in series with the dc power supply to at least partially shield the n-m LED arrays from being bypassed by the m switch cells or the m-x switch cells; or

The n-m LED arrays are located between the DC power source and the m-x switching units in the series loop.

100. A method of controlling an LED array for driving n LED arrays powered by a dc power supply, comprising:

selectively bypassing said n LED arrays to adapt/accommodate said dc power supply when said dc power supply is low enough to not turn on said n LED arrays;

101. The control method of alternate embodiment 100 wherein the step of selectively bypassing the n LED arrays to accommodate the dc power supply further comprises:

Establishing a bypass for a first portion of the n LED arrays respectively across each of the first portion of LED arrays; and/or

And establishing a bypass connected across the second part of the LED arrays in the n LED arrays so as to loop back the direct current power supply by bypassing the second part of the LED arrays.

102. The control method of alternate embodiment 101 wherein the step of selectively bypassing the n LED arrays to accommodate the dc power supply further comprises:

in the first loop, individually bypassing a first part of the n LED arrays, respectively; and/or

And integrally bypassing a second part of the LED arrays at one side of the n LED arrays connected in series to loop back to the DC power supply.

103. The control method of alternate embodiment 101 or 102 further comprising the step of: coordinating currents flowing through at least a portion of the n LED arrays such that power values of the n LED arrays remain in proximity of a first power value.

104. The control method of alternate embodiment 103 wherein the step of coordinating current further comprises: adjusting, in association or in coordination, the current in the first loop and the current in at least one bypass loop formed by the selective bypass such that i) the power of the n LED arrays is maintained in the neighborhood of the first power value during the selective bypass, or ii) the power values of both the first loop and the at least one bypass loop are maintained in the neighborhood of the first power value.

105. The control method of alternative embodiment 104 wherein the dc power supply outputs a pulsating dc voltage and the step of regulating the current further comprises:

i) adjusting the average value of the current in the first loop and the pulsating direct current voltage to be in negative correlation change; and/or the presence of a gas in the gas,

ii) adjusting the current in each of the at least one bypass loop and the conduction voltage drop of the LED array in that bypass loop to vary inversely proportionally.

106. The control method of alternative embodiment 105 wherein the current adjusting step further comprises: i) when the pulsating direct current voltage is lower than a full brightness threshold, reducing the current in the at least one bypass loop along with the increase of the voltage borne by the pulsating direct current voltage/the n LED arrays, or increasing the current in the at least one bypass loop along with the decrease of the voltage borne by the pulsating direct current voltage/the n LED arrays; or

ii) when the pulsating dc voltage is above the full bright threshold, decreasing the current in the first loop as the pulsating dc voltage/voltage sustained by the n LED arrays increases, or increasing the current in the first loop as the pulsating dc voltage/voltage sustained by the n LED arrays decreases;

Thereby, the power of the n LED arrays is kept within a neighborhood of the first power value.

107. The control method of alternative embodiment 106 wherein said pulsing direct current voltage is greater than said full on threshold sufficient to turn on all of said n LED arrays.

108. The control method as in any one of alternative embodiments 103-107, further comprising:

s-1) switching between the first loop and the at least one bypass loop in response to an output voltage of the DC power supply fluctuating around a full bright threshold;

s-2) coordinating the current of the first loop and the current of the at least one bypass loop such that the power of the n LED arrays remains within a neighborhood of a first power value; and, the step S-2) further includes:

s-2-1) in response to the first loop switching to a first type of bypass loop of the at least one bypass loop, adjusting a current in the first type of bypass loop to be greater than a current of the first loop such that a power of the n LED arrays remains within a neighborhood of the first power value before, during, and after a switching process of the first loop to the first type of bypass loop; wherein the bypass loop of the first type corresponds to the first partial LED array; or

S-2-2) in response to the first loop switching to a second type of bypass loop of the at least one bypass loop, adjusting a current in the second type of bypass loop to be greater than a current of the first loop such that a power of the n LED arrays remains within a neighborhood of the first power value before, during, and after a switching process of the first loop to the second type of bypass loop; wherein the second type bypass loop corresponds to the second portion of the LED array; or

S-2-3) in response to the first loop switching to a third type of bypass loop of the at least one bypass loop, adjusting a current in the third type of bypass loop to be greater than a current of the first loop such that the power of the n LED arrays remains within a neighborhood of the first power value before, during, and after the switching process of the first loop to the third type of bypass loop; wherein the third type of bypass loop corresponds to the first and second partial LED arrays; and

the step S-1) further comprises:

in response to the voltage of the DC power supply being below the full on threshold, conducting the at least one bypass loop in the first loop to illuminate a maximum or next-to-maximum number of LED arrays that can be illuminated in the n LED arrays by the voltage of the DC power supply.

109. The control method as in alternative embodiment 108 further comprising the step of:

in response to the first loop switching to one of the first type bypass loop, the second type bypass loop, or the third type bypass loop, alternately turning on at least two of the first type bypass loop, the second type bypass loop, and the third type bypass loop; or

When the voltage of the direct current power supply is lower than the full-bright threshold, at least two of the first type bypass loop, the second type bypass loop and the third type bypass loop are alternatively conducted;

wherein the alternating frequency is greater than the pulsating frequency of the pulsating direct current voltage and is any value of [2kHz,50kHz ].

110. The control method as in alternative embodiment 108 further comprising the step of:

alternately turning on a plurality of the bypass loops of the first type in response to the first loop switching to the bypass loop of the first type; or

In response to the first loop switching to the second type bypass loop, alternately turning on a plurality of the second type bypass loops; or

In response to the first loop switching to the third type bypass loop, alternately turning on a plurality of the third type bypass loops;

Wherein, the alternating conduction frequency is larger than the pulse frequency of the pulse direct current voltage and is any value of [2kHz and 50kHz ].

111. The control method of alternate embodiment 109 or 110 wherein the step of alternately turning on further comprises any of the steps of: i) coordinating currents of at least two of the first type bypass loop, the second type bypass loop, and the third type bypass loop such that power of the n LED arrays is maintained within a neighborhood of the first power value during the alternating conduction; or

ii) coordinating the currents of any one of a) the plurality of bypass loops of the first type, b) the plurality of bypass loops of the second type, c) the plurality of bypass loops of the third type, such that during the alternating conduction, the power of the n LED arrays is maintained in the neighborhood of the first power value.

112. The control method of alternate embodiment 111 wherein the step of current coordinating further comprises:

dynamically controlling the current in the bypass loop of the first type to decrease synchronously with the increase in current in the bypass loop of the second type during switching from the bypass loop of the first type to the bypass loop of the second type, such that the decrease in power in the bypass loop of the first type is compensated/counteracted by the increase in power in the bypass loop of the second type, and

Dynamically controlling the current in the second-type bypass loop to decrease synchronously with an increase in the current in the first-type bypass loop during switching from the second-type bypass loop to the first-type bypass loop, such that a decrease in power in the second-type bypass loop is compensated/counteracted by an increase in power in the first-type bypass loop.

113. The control method of alternative embodiment 112, further comprising:

in the transition process of switching from the second type bypass loop to the first type bypass loop, controlling the current in the first type bypass loop to increase synchronously before the descending amplitude of the current in the second type bypass loop exceeds a preset amplitude value; and/or

In the transition process of switching from the first type bypass loop to a second type bypass loop, controlling the current in the second type bypass loop to increase synchronously before the descending amplitude of the current in the first type bypass loop exceeds the preset amplitude;

wherein the preset amplitude value is any value between 0.1% and 5%.

114. The control method of alternate embodiment 109 wherein the step of alternately turning on further comprises:

alternately conducting the first type bypass loop and the second type bypass loop, thereby distributing the luminous flux of the n LED arrays on the maximum light emitting area; or

Alternately turning on the first-type bypass loop and the second-type bypass loop to illuminate all of the n LED arrays in a single period of the alternate turning on.

115. A method of driving an LED array, comprising: at a drive circuit for driving n LED arrays powered by a dc power supply:

SA-1): detecting the voltage of the direct current power supply; wherein a voltage of the DC power supply above a full brightness threshold is sufficient to turn on the n LED arrays, and a voltage of the DC power supply below the full brightness threshold is insufficient to turn on all of the n LED arrays;

SA-2) rotates/alternately illuminates a first portion of the n LED arrays and all of the n LED arrays in response to/as a voltage of the dc power source changes relative to the full brightness threshold.

116. A method of driving an LED array, comprising: at a drive circuit for driving n LED arrays in series:

SA-1): supplying power to the n LED arrays through a direct current power supply;

SA-2) alternately illuminating a first portion and all of the n LED arrays in response to fluctuations in the dc power supply relative to a full brightness threshold.

117. A method of driving an LED array, comprising: at a driving circuit for driving an array of n mutually coupled LEDs powered by a dc power supply:

SA-1): in response to/if the output voltage of the DC power supply is greater than or equal to a turn-on threshold, driving to illuminate either i) all of the n LED arrays, or ii) a first set of at least one partial LED array of the n LED arrays;

SA-2): driving to illuminate only one of a second set of at least one partial LED array of the n LED arrays in response to/if the output voltage of the DC power supply is below the turn-on threshold.

118. A method of driving an LED array, comprising: at a driving circuit for driving an array of n mutually coupled LEDs powered by a dc power supply:

SA-1): in response to/if the output voltage of the DC power supply is greater than or equal to a turn-on threshold, driving to illuminate one of i) all of the n LED arrays, or ii) a first set of at least one partial LED array of the n LED arrays;

SA-2): and driving to light one of a second set of at least one partial LED array in the n LED arrays in response to/if the output voltage of the DC power supply is lower than the turn-on threshold.

119. The driving method of alternative embodiment 117 or 118, wherein the number of LED arrays in each/any portion of the first set of at least one partial LED arrays is greater than/equal to the number of LED arrays in each/any portion of the second set of at least one partial LED arrays; or

And the conducting voltage drop of the LED array in each/any part of the first group of at least one part of LED arrays is larger than/equal to the conducting voltage drop of the LED array in each/any part of the second group of at least one part of LED arrays.

120. The method of driving as described in alternative embodiment 119 wherein one of said second set of at least one partial LED array has a most/next largest number or a most/next largest on-state voltage drop in said second set of at least one partial LED array.

121. The driving method of alternative embodiment 119, wherein the turn-on threshold comprises a full bright threshold above which the output voltage of the dc power supply is sufficient to turn on all of the n LED arrays.

122. A method of driving an LED array, comprising: at a drive circuit for driving n LED arrays powered by a dc power supply:

SA-2): and responding to/if the output voltage of the direct current power supply is lower than the conduction threshold value, and driving and lighting q LED arrays in the n LED arrays, wherein p and q are integers, and q is less than or equal to p and less than or equal to n.

123. The drive method of alternate embodiment 122 wherein q < p; and/or the conducting voltage drop of the p LED arrays is larger than that of the q LED arrays.

124. The driving method of alternate embodiment 123 wherein the q LED arrays have a maximum/next largest number of the n LED arrays that the output voltage of the dc power supply can turn on below the turn on threshold.

125. The method of driving of alternate embodiment 124 wherein the turn-on threshold comprises a full bright threshold above which the output voltage of the dc power supply is sufficient to turn on all of the n LED arrays.

126. A method of driving an LED array, comprising: at a driving circuit for driving an array of n mutually coupled LEDs powered by a dc power supply:

SA-1): driving illumination of i) all of the n LED arrays, or ii) a greater portion of the n LED arrays, in response to/if the output voltage of the DC power supply is greater than or equal to a turn-on threshold;

SA-2): and driving to light a smaller part of the n LED arrays in response to/if the output voltage of the DC power supply is lower than the conduction threshold.

127. A method of driving an LED array, comprising: at a driving circuit for driving an array of n mutually coupled LEDs powered by a dc power supply:

SA-2): driving to illuminate only a smaller portion of the n LED arrays in response to/if the output voltage of the DC power supply is below the turn-on threshold.

128. A method of driving an LED array, comprising: at a drive circuit for driving n LED arrays powered by a dc power supply:

SA-1): driving the n LED arrays to be illuminated in response to/if the output voltage of the DC power supply is above a full on threshold sufficient to turn on the n LED arrays;

SA-2): only some of the n LED arrays are driven to be illuminated in response to/if the output voltage of the DC power supply is below the full on threshold and is insufficient to turn on all of the n LED arrays.

129. The driving method as set forth in alternative embodiment 128, wherein the step SA-2) further includes the sub-steps of:

SA-2-1) regulating the current through said n LED arrays inversely/inversely related to the conduction voltage drop of said n LED arrays to maintain the power of said n LED arrays within the neighborhood of a first power value; or

The current flowing through the portion of the LED arrays is regulated inversely/inversely related to the on-state voltage drop of the portion of the LED arrays to maintain the power of the portion of the LED arrays within the vicinity of the first power value.

130. The driving method as set forth in alternative embodiment 129, wherein the step SA-2-1) of the partial LED array being a first partial LED array further comprises the substeps of:

SA-2-1-1, coordinating i) the current flowing when said n LED arrays are fully turned on, and ii) the current when said first portion of LED arrays are individually turned on, such that the power of said n LED arrays that are fully turned on and the power of said first portion of LED arrays that are individually turned on are both maintained within the vicinity of said first power value.

131. The drive method as set forth in alternative embodiment 130, wherein the step SA-2-1-1) further comprises the sub-steps of:

in response to a first portion of the LED arrays being individually illuminated, raising a current in the first portion of the LED arrays to a value greater than a current through which the n LED arrays are fully turned on to maintain power of the n LED arrays in the vicinity of the first power value.

132. The drive method as set forth in alternative embodiment 130, wherein the step SA-2-1-1) further comprises the sub-steps of:

I) When the voltage of the direct current power supply is higher than the full brightness threshold value, increasing the current in the n LED arrays along with the reduction of the conduction voltage drop of the n LED arrays; reducing current in the n LED arrays as a conduction voltage drop of the n LED arrays increases; and

II) when the voltage of the direct current power supply is lower than the full brightness threshold value, increasing the current in the first part of LED arrays along with the reduction of the conduction voltage drop of the first part of LED arrays; reducing current in the first portion of the LED array as a conduction voltage drop of the first portion of the LED array increases;

thus, during a variation of the voltage of the direct current power supply, the power of the n LED arrays is kept in the neighborhood of the first power value.

133. The driving method as set forth in any one of alternative embodiments 121, 125, 128, wherein the dc power supply outputs a rectified pulsating voltage, and the step SA-2) further includes a step SA-2-NO):

in response to the lowest value of the ripple voltage falling below the full bright threshold, driving only a portion of the LED array to be illuminated during each of at least one ripple period of the ripple voltage; or

In response to the lowest value of the pulsating voltage falling below the full bright threshold, driving a portion of the LED array to be lit for a full period of at least one pulsating cycle of the pulsating voltage; or

In response to the lowest value of the pulsating voltage falling below the full lighting threshold, a portion of the LED array is driven to be lit for a full period during at least one pulsating cycle of the pulsating voltage.

134. The method of driving of alternate embodiment 133 wherein the portion of the LED array is a first portion of the n LED arrays and a minimum voltage of the pulsed voltage during each pulsed cycle is sufficient to turn on/illuminate the first portion of the LED array.

135. The method of driving of alternate embodiment 134 wherein the portion of the LED arrays are a plurality of portions of the n LED arrays that are individually turned on/illuminated by the minimum voltage of the pulsating voltage in each pulsating cycle.

136. The method of driving of alternate embodiment 134 or 135 wherein the first subset of LED arrays has a maximum or next largest number of the n LED arrays that the lowest value voltage can conduct during the pulsing period of the pulsing voltage; or,

The plurality of partial LED arrays respectively have the maximum number or the next largest number of the minimum voltage in the pulse period of the pulse voltage, which can be conducted in the n LED arrays.

137. The driving method of alternate embodiment 136 wherein the number of LED arrays in the union of the plurality of partial LED arrays is n or n-1.

138. The method of driving as in alternative embodiment 136, further comprising the step of: coordinating i) currents when the n LED arrays are all turned on, and ii) currents when the first portion of LED arrays are individually turned on, such that a total power of the n LED arrays remains within a neighborhood of a first power value.

139. The drive method as set forth in alternative embodiment 135, wherein the step SA-2-NO) further comprises a step SA-2-NO-c): controlling the plurality of partial LED arrays to be cycled on/on at the first predetermined frequency within or across each of the at least one pulsing period in response to the lowest value of the pulsing voltage falling below the full brightness threshold.

140. The drive method of alternative embodiment 133, wherein the step SA-2-NO) further includes a step SA-2-NO-c): in response to the lowest value of the ripple voltage falling below the full brightness threshold, controlling a plurality of portions of the n LED arrays to be cycled on/on at the first predetermined frequency within or across one or more of the at least one ripple period.

141. The driving method as set forth in alternative embodiment 140, wherein the plurality of partial LED arrays further includes a first partial LED array and a second partial LED array, and the step SA-2-NO-c) further includes the steps of:

controlling the first and second partial LED arrays to be alternately or alternately turned on/on at the first predetermined frequency within or across each of the at least one pulsing period in response to the lowest value of the pulsating voltage falling below the full lighting threshold.

142. The driving method as described in any one of alternative embodiments 128, 134, 135, 137, 140 further includes the steps SA-3-NO): performing switching lighting between the n LED arrays and the partial LED array through a plurality of successive ripple periods in response to a change in a lowest value of the ripple voltage across the full brightness threshold; or

Each switching between the n LED arrays and the partial LED array is performed in steps over successive periods of the ripple in response to a change in the lowest value of the ripple voltage across the full brightness threshold; or

Each switching between the n LED arrays and the partial LED array is done step-wise through a consecutive plurality of pulsing periods in response to a change in the lowest value of the pulsating voltage across the full brightness threshold.

143. The drive method as set forth in alternative embodiment 142, wherein the step SA-3-NO) further includes a step SA-3-NO-1):

coordinating an average value of currents in the n LED arrays that are fully turned on and an average value of currents in the partial LED arrays that are individually turned on during switching between the n LED arrays and the partial LED arrays, respectively decreasing and increasing in the plurality of pulsing periods; or

Coordinating the average value of the currents in the n LED arrays that are all turned on with the average value of the currents in the partial LED arrays that are turned on individually, increasing and decreasing respectively in the plurality of ripple periods; or

Coordinating the current or the average value of the current in the n totally conducted LED arrays with the current or the average value of the current in the partial LED arrays which are conducted separately, and respectively presenting an overall ascending trend and an overall descending trend in the plurality of pulse periods.

144. The drive method as set forth in alternative embodiment 142, wherein the step SA-3-NO) further includes a step SA-3-NO-1):

coordinating relative proportions of on-time during which the n LED arrays are fully turned on to on-time during which the partial LED arrays are individually turned on during switching between the n LED arrays and the partial LED arrays, the relative proportions being decremented or incremented during the plurality of pulsing periods; or

In the plurality of pulse periods, coordinating that the duration time for which the n LED arrays are all turned on is increased/decreased cycle by cycle, and correspondingly, the duration time for which the partial LED arrays are individually turned on is decreased/increased cycle by cycle;

wherein the individually turned on partial LED arrays are each of the first partial LED array or the plurality of partial LED arrays turned on alternately.

145. The driving method as set forth in alternative embodiment 143, wherein the step SA-3-NO-1) further includes any one of the following sub-steps:

SA-3-NO-1a) in response to the lowest value of the ripple voltage falling below the full brightness threshold, in the plurality of ripple periods, incrementally adjusting the duty cycle/amplitude of the current in the state where the n LED arrays are fully turned on cycle by cycle, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current in the state where the first portion of LED arrays are individually turned on cycle by cycle; or,

SA-3-NO-1b) in response to the lowest value of the ripple voltage rising above the full brightness threshold, incrementally adjusting the duty cycle/magnitude of the current in the fully on state of the n LED arrays cycle by cycle over the plurality of ripple periods, and, synchronously, incrementally adjusting the duty cycle/magnitude of the current in the individually on state of the first portion of LED arrays cycle by cycle;

SA-3-NO-1c) in response to the lowest value of the ripple voltage falling below the full brightness threshold, during the plurality of ripple periods, incrementally adjusting the duty cycle/amplitude of the current in the state where the n LED arrays are fully turned on cycle by cycle, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current during which the plurality of partial LED arrays are alternately turned on cycle by cycle; or,

SA-3-NO-1d) in response to the lowest value of the ripple voltage rising above the full bright threshold, incrementally adjusting the duty cycle/amplitude of the current in the fully turned on state of the n LED arrays cycle by cycle within the plurality of ripple periods, and, synchronously, incrementally adjusting the duty cycle/amplitude of the current during the period in which the plurality of partial LED arrays are turned on cycle by cycle;

wherein the plurality of pulse periods are adjacent to/correspond to the at least one pulse period in a time domain, and the current of the n LED arrays in the all-on state and the current of the first partial LED array in the single-on state are complementary in time/waveform, or the current of the n LED arrays in the all-on state and the current of the partial LED arrays in the alternate-on state are complementary in time/waveform.

146. The method of driving of alternate embodiment 145 wherein the first predetermined frequency at least partially provides a self-timer/frequency generator and the steps SA-3-NO-1a), SA-3-NO-1b), SA-3-NO-1c), or SA-3-NO-1d) further comprise the steps of:

the full bright threshold is adjusted incrementally/decrementally with the period of the pulsating voltage by an integration unit according to an input from the timer.

147. The method of driving as described in alternative embodiment 142 wherein said plurality of pulsing periods comprises any number of pulsing periods from 5 to 1000 or said plurality of pulsing periods lasts between 1ms and 1000 ms.

148. The driving method as set forth in alternative embodiment 128, wherein the step SA-2) further comprises the step SA-2-F) controlling i) at least one of a first portion of the n LED arrays, and ii) a second portion and/or a third portion of the n LED arrays to be alternately or alternately turned on/off at a first predetermined frequency.

149. The drive method as set forth in alternative embodiment 148, wherein the step SA-2) further includes a step SA-2-F): controlling a plurality of portions of the n LED arrays to be alternately/alternately lit at a first predetermined frequency.

150. The drive method of alternative embodiment 149, wherein the drive method further comprises steps SA-2-F1): keeping at least one LED array of the n arrays other than the rotated plurality of partial LED arrays normally on.

151. The driving method of alternative embodiment 149 or 150, wherein each of the plurality of partial LED arrays is configured to have a maximum or next largest number of the n LED arrays that a lowest value of the ripple voltage can conduct;

I) the union of the plurality of partial LED arrays and the at least one normally-on LED array, or II) the union of the plurality of partial LED arrays, which covers n or n-1 of the n LED arrays; and the LED arrays of the plurality of portions have the same conduction voltage drop.

152. The drive method as set forth in alternative embodiment 151, further comprising steps SA-2-F2): in response to a change/rise in the lowest value of the pulsating voltage with respect to the full-bright threshold, performing switching lighting between the n LED arrays and the partial LED array step by step through a plurality of successive pulsation cycles; or

Switching between the n LED arrays and the partial LED array on in response to a change in the lowest value of the ripple voltage across the full brightness threshold is done step by step through a succession of a plurality of ripple cycles.

153. The drive method as set forth in alternative embodiment 152, wherein the step SA-2-F2) further includes the step SA-2-F25):

gradually adjusting, over the plurality of pulsing periods, the relative proportion of i) the duration of time that the partial LED arrays are alternately illuminated and ii) the duration of time that the n LED arrays are fully illuminated; or,

gradually adjusting the duty ratio/value/average value of a) the currents for alternately lighting the part of the LED arrays and b) the currents for lighting all the n LED arrays in each pulse period.

154. The driving method as set forth in alternative embodiment 153, wherein the step SA-2-F25) further includes: illuminating the n LED arrays by a DC voltage greater than a full illumination threshold in the plurality of pulsing periods; alternately illuminating a portion of the LED arrays at times other than when all of the n LED arrays are illuminated; wherein i) the currents for lighting a portion of the LED arrays are rotated, complementary to ii) the currents for lighting all n LED arrays, in the time domain or in a pulse waveform.

155. The drive method as set forth in alternative embodiment 153, wherein the step SA-2-F25) further includes at least one of the following sub-steps:

i) the duty ratio/value/average value of the current for synchronously and alternately lighting the n LED arrays is increased; or

ii) the duty cycle/value/average value of the current for lighting the partial LED arrays in each of the plurality of pulse periods is increased in coordination with the rotation, and the duty cycle/value/average value of the current for lighting all the n LED arrays in each of the plurality of pulse periods is decreased synchronously;

iii) in said plurality of pulsing periods, the duty cycle/average/amplitude of the current pulses that alternately illuminate said part of the LED arrays is decreased in coordination, and the duty cycle/average/amplitude of the current pulses that illuminate all of said n LED arrays is increased in synchronization;

iiii) coordinating the increasing duty cycle/average/amplitude of the current pulses for alternately illuminating said part of the LED arrays during said plurality of pulsing periods, synchronously the decreasing duty cycle/average/amplitude of the current pulses for illuminating all of said n LED arrays.

156. The driving method as set forth in any one of alternative embodiments 128-132, wherein the step SA-2) and its sub-steps further include:

SA-2-a) controlling a plurality of partial cycles of conduction/ignition of the n arrays corresponding to a first voltage interval within a duration of the first voltage interval in response to a voltage of the dc power source being in the first voltage interval; or

Controlling a plurality of partial cycles of on/ignition of the n arrays corresponding to each of a plurality of first voltage intervals for the duration of the first voltage interval;

wherein the first voltage interval has a voltage range below the full bright threshold; and a plurality of parts of the n LED arrays corresponding to the first voltage interval are circularly conducted in any voltage subinterval or any voltage level in the first voltage interval.

157. The driving method as set forth in any one of alternative embodiments 128-132, wherein the step SA-2) and its sub-steps further include:

SA-2-b) in response to the voltage of the direct current power supply falling into a first voltage interval, controlling a plurality of parts of the n arrays corresponding to the first voltage interval to be circularly conducted; the frequency of the cyclic conduction is greater than, less than or equal to the frequency of the first voltage interval generated along with the voltage change of the direct-current power supply; or

Controlling a plurality of portions of the n arrays corresponding to a plurality of first voltage intervals to be alternately lighted for the duration of the first voltage intervals; wherein one of the plurality of first voltage intervals, or two or more consecutive ones thereof, correspond to only one of the plurality of portions;

The first voltage interval has a voltage range below the full bright threshold.

158. The driving method of alternative embodiment 59 or 60, wherein the corresponding portions of the first voltage interval among the n LED arrays comprise the first and second partial LED arrays;

said step SA-2-a) further comprises the sub-steps of:

SA-2-a-1) alternately turns on the first and second partial LED arrays for the duration of the first voltage interval;

said step SA-2-b) further comprises the sub-steps of:

SA-2-b-1) respectively conducting the first part of LED array and the second part of LED array to two adjacent first voltage intervals in a cyclic mode;

thereby, the power of the n LED arrays within the neighborhood of the first power value is distributed/distributed over the first and second partial LED arrays, and the number of LED arrays in the union of the first and second partial LED arrays is larger than the maximum number of LED arrays in the n LED arrays sufficient to be lit in the first voltage interval.

159. The method of driving as claimed in alternative embodiment 158 wherein, in step SA-2-a-1), the alternating frequency of the alternating conduction is any one of [0.1kHz,1000kHz ].

160. The method of driving of alternate embodiment 158 wherein the first subset of LED arrays and the second subset of LED arrays are both a proper subset of the n LED arrays, the first subset of LED arrays and the second subset of LED arrays do not intersect.

161. The method of driving of alternate embodiment 160 further comprising the step of: keeping a third part of the LED array normally on;

wherein the third partial LED array is non-intersecting with either of the first and second partial LED arrays, having a maximum/next-largest number of LED arrays of the n LED arrays other than the first and second partial LED arrays of the first voltage interval sufficient to conduct.

162. The method of driving of alternative embodiment 158 wherein the first and second partial LED arrays each comprise one or more of the n LED arrays or one or more of the other LEDs of the n LED arrays in series, except for the trailing at least one LED array, to accommodate the first voltage interval.

163. The driving method as claimed in any one of alternative embodiments 158-162, wherein the union of the first partial LED array and the second partial LED array covers/covers all or n-1 of the n LED arrays; or

The number of the first part of LED arrays and the number of the second part of LED arrays are the maximum number/the next largest number of LED arrays that can be lit up in the n LED arrays in the first voltage interval.

164. The method of driving of alternate embodiment 163 wherein said dc power supply outputs a rectified pulsating voltage, said first subset of LED arrays having the same on-state voltage drop as said second subset of LED arrays; the duty cycles of the alternating conduction for the first and second partial LED arrays are each 50%.

165. The method of driving of alternative embodiment 164, wherein the pulsed voltage falls within the first voltage interval a plurality of times within a same pulse cycle or within a plurality of successive pulse cycles, respectively.

166. The drive method of alternate embodiment 164 wherein a plurality of the first voltage intervals occur periodically with the pulsating voltage;

the first voltage intervals occur in the same voltage pulse period in time or are distributed in a plurality of continuous pulse periods.

167. The drive method of alternative embodiment 158, wherein the steps SA-2-a-1) or SA-2-b-1) further comprise: step SA-2-ab-1) coordinates the currents in the first and second partial LED arrays in a cycle of alternating conduction such that the power of the n LED arrays is maintained in the vicinity of the first power value.

168. The driving method as set forth in alternative embodiment 167, wherein the step SA-2-ab-1) further includes:

cooperatively adjusting the current in the first and second partial LED arrays according to the turn-on voltage drops of the first and second partial LED arrays, respectively, such that the relative rate of change of the power of the first and second partial LED arrays during the cycle of alternating turn-on is less than a predetermined percentage;

wherein the predetermined percentage is 0.5%, 2%, or 5%.

169. The drive method as recited in alternative embodiment 168, wherein step SA-2-ab-1) further comprises:

SA-2-ab-1-1) for adjusting the current in said first part of LED arrays to decrease synchronously with the current in said second part of LED arrays before, after and during switching from said first part of LED arrays to said second part of LED arrays, such that the decrease in luminous flux of said first part of LED arrays is compensated/counteracted by the increase in luminous flux of said second part of LED arrays, and

SA-2-ab-1-2) for dynamically controlling the current in said second part of LED arrays to decrease synchronously with the current in said first part of LED arrays before, after and during switching from said second part of LED arrays to said first part of LED arrays, such that the decrease in luminous flux of said second part of LED arrays is compensated/counteracted by the increase in luminous flux of said first part of LED arrays.

170. The drive method of alternate embodiment 169, wherein,

the step SA-2-ab-1-1) further comprises: in the transition process of switching from the second part of LED arrays to the first part of LED arrays, controlling the current in the first part of LED arrays to increase synchronously before the descending amplitude of the current in the second part of LED arrays exceeds a preset amplitude value; and

the step SA-2-ab-1-2) further comprises: in the transition process of switching from the first part of LED arrays to the second part of LED arrays, controlling the current in the second part of LED arrays to be synchronously increased before the descending amplitude of the current in the first part of LED arrays exceeds the preset amplitude;

the preset amplitude value is any value between 0% and 5%.

171. An LED driving apparatus for use in a lighting device, comprising a control unit configured to perform any one of the methods or steps thereof according to alternative embodiments 97-166.

172. An LED driving device for use in a lighting device, comprising: means/modules for performing any one of the methods or steps therein according to alternative embodiments 97-166.

173. A drive circuit for use in a lighting device, comprising: circuit module for performing any one of the methods or steps therein according to alternative embodiments 97-166.

174. A computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a processor/control unit, cause the processor/control unit to perform any of the methods of alternative embodiments 97-166 or the steps thereof.

175. A drive circuit for use in a lighting device, comprising: a storage medium as in alternative embodiment 170, and the processor/control unit.

176. An illumination device, comprising: the driver circuit or the driver apparatus as described in any of alternative embodiments 168-171, and the n LED arrays coupled to and controlled by the driver circuit.

177. The lighting device of alternate embodiment 173, further comprising an electrical signal measurement unit and the dc power supply, the dc power supply comprising a rectifier circuit configured to receive ac input power and rectify the ac input power for output to the n LED arrays; and the electric signal measuring unit is coupled in the lighting device and is configured to measure the output of the rectifying circuit in a voltage or current manner.

178. The lighting device of alternate embodiment 177, wherein the output of the dc power source is connected across an electrolytic capacitor.

179. The lighting device of alternative embodiment 178, wherein n ≧ 2, conduction voltage drops for at least two of the n LED arrays are the same, connected respectively to the first-type bypass loop and the second-type bypass loop that are alternately turned on.

180. The lighting apparatus of alternative embodiment 179, wherein the LED arrays in the first type of bypass loop and the LED arrays in the second type of bypass loop have the same turn-on voltage drop.

181. The lighting device of any of alternative embodiments 92-99 or 176-180, comprising a substrate configured to carry the LED array/the first portion of LEDs in the first bypass loop and the LED array/the second portion of LEDs in the second bypass loop;

the first bypass circuit/the plurality of LEDs in the first part of LEDs and the second bypass circuit/the one or more LEDs in the second part of LEDs are arranged at least partially in a staggered manner, or the first bypass circuit/the plurality of LEDs in the first part of LEDs and the second bypass circuit/the one or more LEDs in the second part of LEDs have an outline area which at least partially overlaps.

182. The lighting device of alternative embodiment 181, wherein one or more LEDs of the second bypass loop/the second portion of LEDs are at least partially dispersed within an outline area of a plurality of LEDs of the first bypass loop/the first portion of LEDs; or

The one or more LEDs of the second load are distributed and at least partially surrounded/surrounded by the first bypass loop/the plurality of LEDs of the first part of LEDs.

183. The lighting device of alternative embodiment 182, wherein one or more of the second bypass loop/the second portion of LEDs are at least partially dispersed within an outline area of a plurality of the first bypass loop/the first portion of LEDs.

184. The lighting device of alternative embodiment 183, wherein an outline area of one or more of the second bypass loop/the second portion of LEDs has an overlap of 60% to 100% with an outline area of a plurality of LEDs in the first bypass loop/the first portion of LEDs.

185. The lighting device of alternative embodiment 184, wherein the area of the profile of one or more of the second bypass loop/the second portion of LEDs is smaller than the area of the profile of the plurality of LEDs in the first bypass loop/the first portion of LEDs by a ratio of at least 10% -40%.

186. The lighting device of any one of alternative embodiments 181-185, wherein the one or more LEDs in the second bypass loop/the second portion of LEDs and the plurality of LEDs in the first bypass loop/the first portion of LEDs are distributed substantially symmetrically around a center of an overall outline area in the array of LEDs in the first bypass loop/the array of LEDs in the first portion of LEDs and the array of LEDs in the second bypass loop/the array of LEDs in the second portion of LEDs.

187. The lighting device of any one of alternative embodiments 181-185, wherein the one or more LEDs of the second bypass loop/the second portion of LEDs and the plurality of LEDs of the first bypass loop/the first portion of LEDs are each arranged centrosymmetrically; and the centre of symmetry of one or more of the second bypass loop/the second part of LEDs and the centre of symmetry of the plurality of LEDs of the first bypass loop/the first part of LEDs substantially coincide.

188. The lighting device of alternative embodiment 187, wherein one of the second bypass loop/the second portion of LEDs is disposed substantially at a center of symmetry of the first bypass loop/the first portion of LEDs, or the plurality of the second bypass loop/the second portion of LEDs and/or the plurality of the first bypass loop/the first portion of LEDs are arranged in a rectangular, circular, annular, curved/linear, symmetrical or asymmetrical radial shape.

189. The lighting device of alternative embodiment 188, wherein the plurality of LEDs in the first bypass loop/first portion of LEDs are distributed within a rectangular, circular, annular, curved/linear, symmetrical, or asymmetrical radial area on the substrate, and one or more LEDs in the second bypass loop/second portion of LEDs are distributed within the plurality of LEDs in the first bypass loop/first portion of LEDs.

190. The lighting device of alternative embodiment 189, wherein one or more of the second bypass loop/the second portion of LEDs are distributed as rectangular, circular, annular, curved/linear, symmetrical or asymmetrical radial; and, in area, the second bypass loop/one or more of the second part of LEDs has a comparable or at least 10% smaller profile area than the first bypass loop/the plurality of first part of LEDs.

191. The lighting device of alternative embodiment 181, wherein the one or more LEDs of the second bypass loop/the second portion of LEDs and the one or more LEDs of the first bypass loop/the first portion of LEDs are adjacently disposed correspondingly or in pairs.

192. A control circuit for use in a lighting device, comprising: a control unit configured to: the method or steps thereof according to any of the alternate embodiments 101-170 are performed when the control circuit is operational or in the on state.

193. In a lighting device, comprising: the driver circuit according to alternate embodiment 192.

194. An illumination device configured to: the method or steps thereof according to any of the alternative embodiments 101-170 are performed when the lighting device is operated or in an operational state.

195. A lighting device comprising one or more circuit modules configured to: the method or steps thereof according to any of the alternative embodiments 101-170 are performed when the lighting device is operated or in an operational state.

In the 90 s of the 20 th century, improvements in a technology could clearly distinguish between improvements in hardware (e.g., improvements in circuit structures such as diodes, transistors, switches, etc.) and improvements in software (improvements in process flow). However, as technology advances, many of today's process flow improvements have been seen as direct improvements in hardware circuit architecture. Designers almost always obtain the corresponding hardware circuit structure by programming an improved method flow into the hardware circuit. Thus, it cannot be said that an improvement in the process flow cannot be realized by hardware physical modules. For example, a Programmable Logic Device (PLD), such as a Field Programmable Gate Array (FPGA), is an integrated circuit whose logic functions are determined by programming the Device by a user. A digital system is "integrated" on a PLD by the designer's own programming without requiring the chip manufacturer to design and fabricate application-specific integrated circuit chips. Furthermore, nowadays, instead of manually making an Integrated Circuit chip, such Programming is often implemented by "logic compiler" software, which is similar to a software compiler used in program development and writing, but the original code before compiling is also written by a specific Programming Language, which is called Hardware Description Language (HDL), and HDL is not only one but many, such as abel (advanced Boolean Expression Language), ahdl (alpha hard ware Description Language), traffic, pl (core unity Programming Language), HDCal (JHDL) jhdware Description Language, langva, Lola, HDL, pamm, hardlaw (Hardware Description Language), and vhjware Description Language (vhlanguage-Language), which is currently used by most popular. It will also be apparent to those skilled in the art that hardware circuitry that implements the logical method flows can be readily obtained by merely slightly programming the method flows into an integrated circuit using the hardware description languages described above.

The control unit may be implemented in any suitable way, for example, the control unit may take the form of, for example, a microprocessor or processor and a computer readable medium storing computer readable program code (e.g., software or firmware) executable by the (micro) processor, logic gates, switches, an Application Specific Integrated Circuit (ASIC), a programmable logic control unit, and an embedded micro-control unit, examples of which include, but are not limited to, the following micro-control units: the ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicone Labs C8051F320, the memory control unit may also be implemented as part of the control logic of the memory. Those skilled in the art will also appreciate that instead of implementing the control unit in pure computer readable program code, it is entirely possible to logically program the method steps such that the control unit performs the same functions in the form of logic gates, timers, flip-flops, switches, application specific integrated circuits, programmable logic control units, embedded micro control units, etc. Such a control unit may thus be regarded as a hardware component and the means included therein for performing the various functions may also be regarded as structures within the hardware component. Or even means for performing the functions may be regarded as being both a software module for performing the method and a structure within a hardware component.

The systems, devices, modules or units illustrated in the above embodiments may be implemented by a computer chip or an entity, or by a product with certain functions. One typical implementation device is a computer. In particular, the computer may be, for example, a personal computer, a laptop computer, a cellular telephone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

For convenience of description, the above devices are described as being divided into various units by function, and are described separately. Of course, the functionality of the units may be implemented in one or more software and/or hardware when implementing the present application.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The application may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular transactions or implement particular abstract data types. The application may also be practiced in distributed computing environments where transactions are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, so that various optional technical features can be combined with other embodiments in any reasonable manner, and the contents among the embodiments and under various headings can be combined in any reasonable manner. Each embodiment is described with emphasis on differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, and "a plurality" typically includes at least two. It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.

Claims

2. The lighting device is characterized by being manufactured by adopting the control circuit.

3. A control circuit for driving an at least partially series connected array of n LEDs powered by a dc power source, the control circuit comprising:

a control unit;

m switch units configured to respectively correspondingly couple m of the n LED arrays when the control circuit drives the n LED arrays, respective control terminals of the m switch units being respectively connected to the control unit, controlled by the control unit to bypass the corresponding LED arrays;

4. The control circuit of claim 3, wherein the m switching units bypass the corresponding one or more LED arrays by being controlled by selective conduction of the control unit.

5. The control circuit of claim 4, wherein x of the m switch units are correspondingly connected in parallel with x of the m LED arrays, and the remaining m-x switch units are respectively correspondingly connected between one end of the remaining m-x LED arrays and the DC power output terminal, and the m-x switch units are respectively operable/conductive to allow the DC power to be looped back from the corresponding end of each of the m-x LED arrays, wherein x is an integer, m is greater than or equal to 2, and m is greater than or equal to x is greater than or equal to 0.

6. A driving circuit comprising the control circuit according to any one of claims 1 or 3-5, integrated as a chip; and, the n LED arrays peripherally coupled to the chip.

7. A method of controlling an LED array for driving n LED arrays in series powered by a dc power source, comprising:

8. The control method of claim 7, wherein said step of selectively bypassing said n LED arrays to accommodate said dc power supply further comprises:

9. The control method of claim 8, wherein said step of selectively bypassing said n LED arrays to accommodate said dc power supply further comprises:

10. The control method according to claim 8 or 9, further comprising the step of: coordinating currents flowing through at least a portion of the n LED arrays such that power values of the n LED arrays remain in proximity of a first power value.