CN110798935B

CN110798935B - LED lamp string control method, device and system and terminal equipment

Info

Publication number: CN110798935B
Application number: CN201911135594.6A
Authority: CN
Inventors: 黎海明; 李永红
Original assignee: Shenzhen Ocx Semiconductor Co ltd
Current assignee: Shenzhen Ocx Semiconductor Co ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2021-10-08
Anticipated expiration: 2039-11-19
Also published as: CN110798935A

Abstract

The application is applicable to the technical field of LED control, and provides an LED lamp string control method, an LED lamp string control device, an LED lamp string control system and terminal equipment, wherein the LED lamp string control method comprises the following steps: acquiring a first current value, wherein the first current value is a current value flowing through the LED lamp string when the LED lamp string is in a working state; detecting the LED units with open circuit faults in all the LED units of the LED lamp string under the conditions that the first current value is smaller than a first preset current value and the duration time exceeds a first preset time; and controlling the LED unit with the open-circuit fault to be converted into a short-circuit state in the case of detecting the LED unit with the open-circuit fault. The problem of in the LED dimming control circuit one LED lamp break circuit lead to whole circuit to become invalid is solved.

Description

LED lamp string control method, device and system and terminal equipment

Technical Field

The application belongs to the technical field of LED control, and particularly relates to a method, a device and a system for controlling an LED lamp string and terminal equipment.

Background

In the application of the traditional stage lamp, the LED lamp string is formed by connecting a plurality of LED lamps in series, and when dimming and color mixing are needed, the duty ratio of each path of PWM signal is controlled to control one switch tube connected with the LED lamps in parallel, so that the dimming and color mixing functions of the LEDs are realized.

As shown in fig. 1, which is a schematic circuit connection diagram of a conventional LED light string, a plurality of LEDs are connected in series, and each driving chip modulates color of the LED by adjusting a duty ratio of an output PWM signal. However, when one of the LEDs is disconnected, the entire LED string cannot work normally.

Disclosure of Invention

The embodiment of the application provides a method, a device and a system for controlling an LED lamp string and terminal equipment, which can solve the problem that in the prior art, the whole circuit is invalid due to the fact that one LED lamp in the LED lamp string is broken.

The application is realized by the following technical scheme:

in a first aspect, an embodiment of the present application provides a method for controlling an LED light string, including:

acquiring a first current value, wherein the first current value is a current value flowing through the LED lamp string when the LED lamp string is in a working state;

detecting the LED units with open circuit faults in all the LED units of the LED lamp string under the conditions that the first current value is smaller than a first preset current value and the duration time exceeds a first preset time;

and controlling the LED unit with the open-circuit fault to be converted into a short-circuit state in the case of detecting the LED unit with the open-circuit fault.

In a possible implementation manner of the first aspect, the detecting the LED unit having an open-circuit fault in each of the LED units of the LED light string includes:

controlling each LED unit to be in a working state independently;

acquiring a second current value when each LED unit is in a working state independently;

and if the second current value is smaller than a second preset current value, determining that the corresponding LED unit has an open circuit fault.

In a possible implementation manner of the first aspect, the method further includes:

reducing the first current value when the first current value is larger than the maximum value of a third preset current range;

increasing the first current value when the first current value is less than a minimum value of the third preset current range.

In a second aspect, an embodiment of the present application provides an LED string control device, including:

the current acquisition module is used for acquiring a first current value, wherein the first current value is a current value flowing through the LED lamp string when the LED lamp string is in a working state;

the open circuit detection module is used for detecting the LED units with open circuit faults in all the LED units of the LED lamp string under the conditions that the first current value is smaller than a first preset current value and the duration time exceeds a first preset time;

and the driving module is used for controlling the LED unit with the open-circuit fault to be converted into a short-circuit state under the condition that the LED unit with the open-circuit fault is detected.

In a possible implementation manner of the second aspect, the LED light string control device further includes a constant current control module, where the constant current control module includes:

the first constant current control module is used for reducing the first current value under the condition that the first current value is larger than the maximum value of a third preset current range;

and the second constant current control module is used for increasing the first current value under the condition that the first current value is smaller than the minimum value of the third preset current range.

In a third aspect, an embodiment of the present application provides an LED light string control system, which includes a plurality of LED units connected in series, a current collection unit, and a control unit;

each LED unit comprises an LED lamp and a first switch tube which are connected in parallel, the current acquisition unit is connected with the LED units in series, the current acquisition unit and all the first switch tubes are connected with the control unit, and the control unit is the LED lamp string control device in any one of the second aspects;

the control unit obtains the first current value through the current acquisition unit.

In a possible implementation manner of the third aspect, the LED light string control system further includes a second switching tube;

the second switch tube is connected in series between the plurality of LED units connected in series and the power supply and used for controlling the working current of the LED units according to the instruction of the control unit.

In a possible implementation manner of the third aspect, the LED light string control system further includes a first inductor;

the first inductor is connected in series between the second switch tube and the plurality of LED units connected in series.

In a fourth aspect, an embodiment of the present application provides a terminal device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements the LED string control method according to any one of the above first aspects when executing the computer program.

In a fifth aspect, the present application provides a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the method for controlling an LED light string according to any one of the above first aspects is implemented.

It is understood that the beneficial effects of the second aspect to the fifth aspect can be referred to the related description of the first aspect, and are not described herein again.

Compared with the prior art, the embodiment of the application has the advantages that:

when the LED lamp string works, a first current value of the LED lamp string in a working state is obtained, and when the first current value is smaller than a first preset current value and the duration time exceeds a first preset time, the fact that an LED unit in the LED lamp string breaks down can be determined. And detecting all the LED units in the LED lamp string, determining the LED unit with the open circuit fault, controlling the LED unit with the fault to be converted into a short circuit state after the detection is finished, and then controlling the LED lamp string to enter a working state. When an LED unit in the LED lamp string has an open-circuit fault, the LED unit with the open-circuit fault is subjected to short circuit, so that the normal work of other LED units is not influenced, and the LED lamp string can still work normally.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic circuit diagram of a conventional LED light string;

fig. 2 is a schematic flow chart illustrating an implementation of a method for controlling an LED light string according to an embodiment of the present application;

FIG. 3 is a schematic block diagram of an LED light string control device according to an embodiment of the present disclosure;

FIG. 4 is a functional block diagram of a control unit provided in an embodiment of the present application;

FIG. 5 is a schematic circuit diagram of an LED light string control system according to an embodiment of the present disclosure;

FIG. 6 is a schematic circuit diagram of an LED light string control system according to another embodiment of the present application;

FIG. 7 is a timing diagram illustrating operation of an LED light string control system according to an embodiment of the present disclosure;

fig. 8 is a schematic structural diagram of a terminal device according to an embodiment of the present application.

In the figure: 510. a current collection unit; 520. a power supply; 530. an LED unit.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, 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.

It should also be understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

As used in this specification and the appended claims, the term "if" may be interpreted contextually as "when", "upon" or "in response to" determining "or" in response to detecting ". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.

Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

The traditional LED lamp string comprises a plurality of LED units which are sequentially connected in series, each LED unit comprises a switch tube and an LED lamp which are connected in parallel, each LED unit corresponds to one driving chip, and the driving chips control the switch tubes to be switched on or switched off through outputting PWM signals so as to realize the adjustment of the brightness and the chromaticity of the LED lamps. However, when the LED lamp in the LED lamp string has an open circuit fault, the whole circuit is open circuit, and the LED lamp string cannot work normally.

In order to solve the problem that the whole light string cannot work due to the fact that an individual LED lamp in the LED light string is broken, the working current of the LED lamp can be collected. And when the LED lamps in the LED lamp string are broken, detecting all the LED units in the LED lamp string, and confirming the LED unit with the fault. The switch tube in the LED unit for controlling the open circuit fault is always in a closed state so as to realize that the LED with the open circuit fault is converted into a short circuit state, other LED units in the LED lamp string cannot be influenced, and the LED lamp string can still work normally.

The following describes the LED string control method in the embodiments of the present application in detail.

As shown in fig. 2, a schematic flow chart of an implementation of the LED light string control method according to an embodiment of the present application is detailed as follows:

step S201, a first current value is obtained, where the first current value is a current value flowing through the LED light string when the LED light string is in a working state.

Specifically, when the LED light string works, the current in the circuit is collected to obtain a first current value, and since the current signal changes during the working process of the LED light string, the collection of the circuit current may be continuous or periodic, and the first current value is continuously updated to obtain an accurate working current of the LED light string.

Step S202, under the condition that the first current value is smaller than a first preset current value and the duration time exceeds a first preset time, detecting an LED unit with an open circuit fault in each LED unit of the LED lamp string.

It should be noted that the first preset current value may be obtained through experiments or experiences, and the first preset current value is a limit current value for normal operation of the LED light string. For example, the first preset current value may be set to a value close to zero, when the first current value of the working current of the LED light string is smaller than the first preset current value, it is indicated that the LED light string fails, and because the current of the LED light string becomes very small, it may be determined that the LED light string has an open circuit failure. When the LED lamp string is judged to have the open circuit fault, all the LED units in the LED lamp string are detected so as to position the LED units with the fault.

Specifically, the method for detecting the LED units with open circuit faults in the LED units of the LED lamp string comprises the following steps:

and step A, controlling each LED unit to be in a working state independently.

It should be noted that, when the LED light string works, the switch tube in the LED unit receives the pulse signal to turn on or off, so as to control the light emitting diode connected in parallel with the switch tube to emit light and color. Therefore, each LED unit can work in two states, namely, a working state (the switch tube is open, the light emitting diode is connected in series in the circuit) and a short-circuit state (the switch tube is closed, and the light emitting diode connected in parallel with the switch tube is short-circuited).

When the LED units are controlled to be in the working state independently, other LED units in the LED lamp string are in the short-circuit state, and only one LED in the circuit is in the working state.

And B, acquiring a second current value when each LED unit is in a working state independently.

When only one LED unit in the LED lamp string is in a working state, the current in the circuit at the moment is collected, namely the current is the second current value when the LED unit is in the working state independently.

And obtaining a current signal, namely a second current value, of all the LED units in the LED lamp string in the working state independently through the step A and the step B, and then positioning the LED unit with the fault according to the second current value.

And step C, if the second current value is smaller than a second preset current value, judging that the corresponding LED unit has an open circuit fault.

It should be noted that the second preset current value may be obtained through experiments or experiences, and the second preset current value is a limit current value of normal operation of the LED unit. For example, the second preset current value may be set to a value close to zero, and when the second current value of the operating current of the LED unit is smaller than the second preset current value, it indicates that the LED unit has an open-circuit fault.

Further, a fourth preset current range value can be set, the current of the LED unit working normally is within the fourth preset current range value, and when the detected second current value of the LED unit in the working state is within the fourth preset current range value, it is determined that the LED unit has no fault.

In step S203, when the LED unit having the open-circuit fault is detected, the LED unit having the open-circuit fault is controlled to be switched to the short-circuit state.

The LED unit with the open circuit fault can be located through step S202, and after the scanning is completed, the LED unit with the fault is controlled to be switched to the short circuit state. Because the LED unit with the open circuit fault is in a short circuit state, a short circuit is formed at the open circuit position of the LED lamp string, the circuit can still work normally, and the open circuit LED unit cannot influence other normal LED units.

In some embodiments, the LED light string control method further comprises:

and step I, reducing the first current value under the condition that the first current value is larger than the maximum value of the third preset current range.

And II, increasing the first current value under the condition that the first current value is smaller than the minimum value of the third preset current range.

The working current of the LED lamp string can be maintained in the third preset current range through the step I and the step II, constant current control is achieved, the phenomenon that the LED lamp string is damaged by elements in a circuit due to the fact that the current is too large or too small when the LED lamp string works is avoided, and the stability of the LED lamp string is improved.

As shown in fig. 3, the present application further discloses an LED string light control device, comprising:

the current obtaining module 310 is configured to obtain a first current value, where the first current value is a current value flowing through the LED light string when the LED light string is in a working state;

the open circuit detection module 320 is configured to detect an LED unit with an open circuit fault in each LED unit of the LED light string when the first current value is smaller than a first preset current value and the duration time exceeds a first preset time;

and the driving module 330 is configured to control the LED unit with the open-circuit fault to be switched to the short-circuit state when the LED unit with the open-circuit fault is detected.

The current obtaining module 310 obtains a first current value when the LED lamp string is in a working state, when the first current value is smaller than a first preset current value and the duration time exceeds a first preset time, the open-circuit detecting module 320 detects each LED unit in the LED lamp string and determines the LED unit with the open-circuit fault, and the driving module 330 controls the LED unit with the open-circuit fault to be switched to a short-circuit state, so that the open-circuit part in the LED lamp string is short-circuited, and the LED lamp string can still work normally.

In an embodiment of the present application, the LED string control device further includes a constant current control module 340, where the constant current control module includes:

the first constant current control module is used for reducing the first current value under the condition that the first current value is larger than the maximum value of the third preset current range;

The application also discloses an LED lamp string control system which can comprise a plurality of LED units, a current acquisition unit and a control unit which are connected in series; each LED unit comprises an LED lamp and a first switch tube which are connected in parallel, the current acquisition unit is connected with the LED units in series, the current acquisition unit and all the first switch tubes are connected with the control unit, and the control unit is the LED lamp string control device.

When the LED lamp string works, the current acquisition unit acquires a current signal when the LED lamp string works to obtain a first current value, and the first current value is transmitted to the control unit. The control unit judges whether an LED unit has an open circuit fault or not according to the first current value, and when the first current value is smaller than a first preset current value and the duration time exceeds a first preset time, the control unit judges that the LED unit has the open circuit fault in the LED lamp string. Then the control unit detects all the LED units in the LED lamp string, and each LED unit is in an independent working state by controlling the first switch tube. The current acquisition unit acquires a current signal of the LED unit in a working state independently to obtain a second current value. And the control unit compares the second current value with a second preset current value to judge whether the LED unit has an open circuit fault. After the detection is finished, the control unit controls the LED unit with the open circuit fault to be converted into a short circuit state, the normal work of other LED units is not influenced, and the LED lamp string can still work normally.

The LED string control system in the embodiments of the present application will be described in detail below.

For convenience of description, the LED light string control system in the embodiment of the present application is described below by taking four LED lights connected in series as an example, in other embodiments, the number of the LED lights may be set to any value other than four to meet an actual requirement, and the number of the LED lights in the embodiment of the present application is not particularly limited.

As shown in fig. 4, which is a schematic block diagram of the control unit U1 provided in this embodiment of the present application, the control unit U1 includes a current obtaining module 310, an open-circuit detecting module 320, a driving module 330, and a constant current control module 340, where the current obtaining module 310 is configured to obtain a first current value, and the open-circuit detecting module 320 determines whether an LED unit in the LED string has an open-circuit fault according to the first current value. When an LED unit in the LED string has an open-circuit fault, the open-circuit detection module 320 controls each LED unit to be in an operating state independently by controlling the driving module 330. The current obtaining module 310 collects a second current value when the LED units are individually in a working state, and transmits the second current value to the open circuit detecting module 320. The open circuit detection module 320 determines the LED unit having the open circuit fault according to the second current value, and controls the LED unit having the open circuit fault to be switched to the short circuit state through the driving unit. The constant current control module 340 can maintain the working current of the LED light string within a set current range, thereby improving the stability of the LED light string.

As shown in fig. 5, which is a schematic circuit connection diagram of an LED string control system according to an embodiment of the present disclosure, the LED string control system may include four LED units 530 sequentially connected in series, where each LED unit 530 includes an LED lamp and a first switch tube connected in parallel. The first switch tube Q1 is connected in parallel with the LED lamp D1, the first switch tube Q2 is connected in parallel with the LED lamp D2, the first switch tube Q3 is connected in parallel with the LED lamp D3, and the first switch tube Q4 is connected in parallel with the LED lamp D4. The current collection unit 510 is connected in series with the LED lamp, the output port of the current collection unit 510 and the plurality of first switching tubes are respectively connected to different ports of the control unit U1, wherein the control ends of the four first switching tubes are respectively connected to the DRV1 port, the DRV2 port, the DRV3 port and the DRV4 port of the control unit U1, and two terminals of the current collection unit 510 are respectively connected to the VSP port and the VSN port of the control unit U1. The control unit U1 receives PWM control signals through different ports and respectively sends pulse signals through a DRV1 port, a DRV2 port, a DRV3 port and a DRV4 port to control the action of the corresponding first switch tube, so that the LED lamp is lightened and color is adjusted.

In operation, the current collecting unit 510 collects a current signal in the circuit in real time to obtain a first current value, and transmits the first current value to the control unit U1 through the VSP port and the VSN port. The control unit U1 compares the first current value with a preset first current value, and when the first current value is smaller than the first preset current value and the duration time exceeds a first preset time, the control unit U1 determines that the LED lamp in the circuit has an open circuit fault. The first predetermined current value may be set to zero or a small value, for example, when the current in the circuit is zero or small, an open circuit fault occurs in the circuit with the LED lamp. When the control unit U1 determines that there is an LED lamp in the circuit that has an open circuit fault, each LED is controlled to be in an operating state individually, and other LED lamps are in a short circuit state, for example, the control unit U1 controls the first switch tube Q1 to be open and controls other first switch tubes to be closed, so as to implement the LED lamp D1 to operate individually. The current collecting unit 510 collects current of the individual LED lamps in a working state to obtain a second current value. The control unit U1 compares the second current value with a preset second current value, and confirms that the LED lamp has an open-circuit fault when the second current value is smaller than the second preset current value. The second preset current value may be set to zero or a small value, and when the current of the LED lamp in the operating state alone is zero or very small, it is determined that the LED lamp has an open-circuit fault. And repeating the steps, and checking all the LED lamps in the circuit one by one to determine the LED lamp with the open circuit fault. After the LED lamp with the open-circuit fault is determined, the control unit U1 controls the first switch tube corresponding to the LED lamp with the open-circuit fault to be in the normally closed state, so that the LED lamp with the open-circuit fault is short-circuited, and the normal operation of other LED lamps is not affected.

It should be noted that, two terminals of the current collecting unit 510 are respectively connected to the VSP port and the VSN port of the control unit U1, the control unit U1 can collect the voltage across the current collecting unit 510, and then the current signal of the circuit can be obtained according to the resistance of the current collecting unit 510 and the voltage across the current collecting unit 510. The current collecting unit 510 herein does not only directly collect the current signal in the circuit, but also collects some determined signals and calculates to obtain the current signal in the circuit.

Fig. 6 is a schematic circuit connection diagram of an LED string control system according to another embodiment of the present application, where the LED string control system may further include a second switching tube QZ based on fig. 5; the second switching tube QZ is connected in series between the LED lamp and the power supply 520, and is used for controlling the working current of the LED lamp according to the instruction of the control unit U1.

The current collecting unit 510 can collect a current signal of the LED lamp during operation to obtain a first current value, and transmit the first current value to the control unit U1, the control unit U1 generates a pulse signal according to the first current value collected by the current collecting unit 510, and transmits the pulse signal to a control end of the second switching tube QZ, and the second switching tube QZ is turned on or off according to the pulse signal to change the operating current of the LED lamp. For example, when the operating current of the LED is too small, the control unit U1 increases the duty ratio of the output pulse signal, and the second switching tube QZ increases the operating current of the LED lamp according to the high duty ratio pulse signal; when the current of the LED lamp is too large, the control unit U1 reduces the duty ratio of the output pulse signal, and the second switching tube QZ reduces the working current of the LED lamp according to the pulse signal of the second duty ratio, so that the working current of the LED lamp is controlled within a set range, the constant current control of the LED lamp is realized, and the working stability of the LED lamp is improved.

Further, the LED string control system may further include a first inductor L1, and the first inductor L1 is connected in series between the second switching tube QZ and the LED lamp.

When the second switching tube QZ is closed, the current of the LED lamp gradually increases because the first inductor L1 is connected in series to the LED lamp circuit; when the second switch tube QZ is turned off, the first inductor L1 discharges and the current of the LED lamp gradually decreases. The first inductor L1 plays a role in current buffering, so that the working current of the LED lamp is slowly changed, and the working stability of the LED lamp is improved.

Further, the LED string control system may further include a freewheeling diode DZ, an anode of the freewheeling diode DZ is grounded, and a cathode of the freewheeling diode DZ is connected to the common terminal of the second switch tube QZ and the first inductor L1.

The freewheeling diode DZ is also called a flywheel diode, and is a diode used in conjunction with an inductive load, and when the current of the inductive load suddenly changes or decreases, a sudden voltage is generated across the inductor, which may damage other components.

When the second switch tube QZ is switched from on to off, the first inductor L1 provides continuous current for the LED lamp through the freewheeling diode DZ within a period of time, and the freewheeling diode DZ plays a role in smoothing current, so as to prevent the circuit from being damaged by sudden change of current in the circuit, and play a role in protecting components in the circuit.

In the embodiment of the present application, the current collecting unit 510 in the LED string control system may be connected in series at any position in the circuit, for example, between two LED lamps, or between an LED lamp and the power supply 520, or between an LED lamp and the ground.

Preferably, the current collecting unit 510 is connected in series between one LED lamp and the ground, and when the second switching tube QZ is in an on state or an off state, the current collecting unit 510 can collect the operating current of the LED lamp.

Specifically, the current collecting unit 510 may include a first resistor RCS, one end of the first resistor RCS is connected to one LED lamp and the control unit U1, respectively, and the other end of the first resistor RCS is grounded.

The control unit U1 can realize the collection of LED lamp operating current through gathering the partial pressure and the resistance of first resistance RCS in the circuit, obtains first current value.

In an embodiment of the present application, the control unit U1 may include a plurality of voltage stabilizing units, where the plurality of voltage stabilizing units correspond to the plurality of first switching tubes one to one, and an output end of each voltage stabilizing unit is connected to a source electrode of the corresponding first switching tube.

During operation, the control unit U1 sends pulse signals to a plurality of first switch tubes through different ports, and the first switch tubes are switched on or off according to the pulse signals to realize the adjustment of the corresponding LED lamp chromaticity. Because a plurality of LED lamps are connected in series, each LED lamp is connected with one first switch tube in parallel, the plurality of first switch tubes are connected in series, and when the plurality of first switch tubes are conducted, the source power supply of the first switch tubes is reduced. The voltage stabilizing unit can supplement voltage to a source electrode of the first switching tube to drive the first switching tube to normally work.

Specifically, the voltage stabilizing unit may include capacitors (C1, C2, C3, and C4 in fig. 6), one end of each capacitor is connected to the high voltage signal terminal inside the control unit U1, and the other end of each capacitor is connected to the source of the corresponding first switch tube and the low voltage signal terminal inside the control unit U1. Therefore, a bootstrap capacitor is formed to provide a driving voltage for the corresponding first switch tube.

In the embodiment of the application, the first switch tube may be an N-type MOS tube or a P-type MOS tube, and the second switch tube QZ may also be an N-type MOS tube or a P-type MOS tube.

Fig. 7 is a timing chart illustrating an operation of the LED string control system according to the embodiment of the present invention.

In a period T1, the control unit U1 is powered on normally, the internal LDO and the bootstrap circuit start working, and the control unit U1 controls the second switch tube QZ to be turned on through the PGATE port. The current flowing through the first inductor L1 increases slowly from zero, and the current flows through the first resistor RCS to obtain a first current value and is transmitted to the current acquisition module 310 of the control unit U1 through the VSN port and the VSP port. When the first current value reaches the maximum value of the third preset current range, the constant current control module 340 of the control unit U1 generates a PGATE signal to control the on and off of the second switching tube QZ, so as to output a constant current. The driving module 330 in the control unit U1 outputs a DRV1 pulse signal, a DRV2 pulse signal, a DRV3 pulse signal and a DRV4 pulse signal through a DRV1 port, a DRV2 port, a DRV3 port and a DRV4 port to control the four first switching tubes to be turned on and off, so as to implement a dimming operation. The enable signal OPEN _ DECT _ EN of the OPEN circuit detection block 320 is low at this time.

In the period T2, the first current value detected by the current obtaining module 310 is zero and lasts for the first preset time, and the open circuit detecting module 320 is triggered.

In the period of T3, the enable signal OPEN _ DECT _ EN of the OPEN circuit detection module 320 goes high, and the driving module 330 forcibly turns on the individual LED lamps one by shielding the DRV1 pulse signal, the DRV2 pulse signal, the DRV3 pulse signal, and the DRV4 pulse signal. And if the second current value of the LED lamp is smaller than the second preset current value in the starting time period, the LED lamp has an open circuit fault, and after the detection is finished, the driving unit controls the first switch tube corresponding to the faulty LED lamp to be in a closed state through the DRV port so that the faulty LED lamp is short-circuited. If the second current value of the LED lamp is larger than the second preset current value in the starting time period, the LED lamp is normal, and after the detection is finished, the driving unit normally controls the LED lamp through the DRV port. In the example of fig. 7, the third LED has an open circuit fault.

In the period of T4, the enable signal OPEN _ DECT _ EN of the OPEN circuit detection module 320 becomes low, and the driving module 330 controls the first switch tube corresponding to the failed LED lamp to be in a closed state through the DRV3 port, so that the failed LED lamp is short-circuited.

It should be noted that, for the information interaction, execution process, and other contents between the above-mentioned devices/units, the specific functions and technical effects thereof are based on the same concept as those of the embodiment of the method of the present application, and specific reference may be made to the part of the embodiment of the method, which is not described herein again.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

Fig. 8 is a block diagram for implementing a terminal device 8 according to an embodiment of the present disclosure, and includes a processor 81, a memory 82, and a computer program 83 stored in the memory 82 and executable on the processor 81, where the processor 81 executes the computer program 83 to implement the steps in any of the LED string control method embodiments. Such as step S201 through step S203 shown in fig. 2.

Illustratively, the computer program 83 may be partitioned into one or more modules/units that are stored in the memory 82 and executed by the processor 81 to carry out the invention. The one or more modules/units may be a series of instruction segments of the computer program 83 capable of performing specific functions, which are used to describe the execution process of the computer program 83 in the terminal device 8.

The terminal device 8 may be a desktop computer, a notebook, a palm computer, a cloud server, or other computing devices. The terminal device 8 may include, but is not limited to, a processor 81, a memory 82. Those skilled in the art will appreciate that fig. 8 is merely an example of the terminal device 8, and does not constitute a limitation of the terminal device 8, and may include more or less components than those shown, or combine some components, or different components, such as an input-output device, a network access device, and the like.

The Processor 81 may be a Central Processing Unit (CPU), and the Processor 81 may also be other general-purpose Processor 81, a Digital Signal Processor 81 (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA) or other Programmable logic device, a discrete Gate or transistor logic device, a discrete hardware component, and so on. The general purpose processor 81 may be a microprocessor 81 or the processor 81 may be any conventional processor 81 or the like.

The memory 82 may in some embodiments be an internal storage unit of the terminal device 8, such as a hard disk or a memory of the terminal device 8. The memory 82 may also be an external storage device of the terminal device 8 in other embodiments, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like, which are provided on the terminal device 8. Further, the memory 82 may also include both an internal storage unit and an external storage device of the terminal device 8. The memory 82 is used for storing an operating system, an application program, a BootLoader (BootLoader), data, and other programs, such as program codes of the computer program 83. The memory 82 may also be used to temporarily store data that has been output or is to be output.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus/network device and method may be implemented in other ways. For example, the above-described apparatus/network device embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implementing, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the methods of the embodiments described above can be implemented by a computer program 83 to instruct related hardware, where the computer program 83 can be stored in a computer readable storage medium, and when the computer program 83 is executed by the processor 81, the steps of the methods described above can be implemented. Wherein the computer program 83 comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include at least: any entity or device capable of carrying computer program code to the photographing apparatus/terminal apparatus 8, a recording medium, computer Memory, Read-Only Memory (ROM), Random Access Memory (RAM), an electrical carrier signal, a telecommunications signal, and a software distribution medium. Such as a usb-disk, a removable hard disk, a magnetic or optical disk, etc. In certain jurisdictions, computer-readable media may not be an electrical carrier signal or a telecommunications signal in accordance with legislative and patent practice.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.

Claims

1. An LED lamp string control method is characterized by comprising the following steps:

controlling the LED unit with the open-circuit fault to be converted into a short-circuit state under the condition that the LED unit with the open-circuit fault is detected;

the LED unit for detecting the existence of open circuit fault in each LED unit of the LED lamp string comprises:

controlling each LED unit to be in a working state independently;

2. The LED light string control method of claim 1, further comprising:

3. An LED light string control device, comprising:

the driving module is used for controlling the LED unit with the open-circuit fault to be converted into a short-circuit state under the condition that the LED unit with the open-circuit fault is detected;

controlling each LED unit to be in a working state independently;

4. The LED light string control device according to claim 3, further comprising a constant current control module, wherein the constant current control module comprises:

5. An LED lamp string control system is characterized by comprising a plurality of LED units, a current acquisition unit and a control unit which are connected in series;

each LED unit comprises an LED lamp and a first switch tube which are connected in parallel, the current acquisition unit is connected with the LED units in series, the current acquisition unit and all the first switch tubes are connected with the control unit, and the control unit is the LED lamp string control device according to any one of claims 3 or 4;

6. The LED light string control system according to claim 5, further comprising a second switch tube;

7. The LED light string control system of claim 6, further comprising a first inductor;

8. A terminal device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the LED light string control method according to claim 1 or 2 when executing the computer program.

9. A computer-readable storage medium, in which a computer program is stored, which, when being executed by a processor, implements the LED light string control method according to claim 1 or 2.