CN111885764A

CN111885764A - Power supply circuit and lamp

Info

Publication number: CN111885764A
Application number: CN202010682139.4A
Authority: CN
Inventors: 蔡显彬
Original assignee: Ningbo Gongniu Optoelectronics Technology Co Ltd
Current assignee: Ningbo Gongniu Optoelectronics Technology Co Ltd
Priority date: 2020-07-15
Filing date: 2020-07-15
Publication date: 2020-11-03
Anticipated expiration: 2040-07-15
Also published as: CN111885764B

Abstract

The application provides a power supply circuit and a lamp, and belongs to the technical field of electronics. A dimming circuit in the power supply circuit is connected with the input end of the secondary rectification circuit, and the on-off state of the switch can be determined by directly detecting a signal at the input end of the secondary rectification circuit. Because the signal at the input end of the secondary rectification circuit belongs to a weak current signal relative to the power supply signal, an isolation element does not need to be additionally arranged between the dimming circuit and the input end of the secondary rectification circuit to ensure the working safety of the dimming circuit, and the design of the power supply circuit is beneficial to realizing the miniaturization of the lamp.

Description

Power supply circuit and lamp

Technical Field

The present application relates to the field of electronic technologies, and in particular, to a power circuit and a lamp.

Background

Dimmable light fixtures refer to light fixtures in which the lighting parameters (including at least one of brightness and color temperature) are adjustable. Generally, a user can adjust the light emitting parameters of the dimmable lamp by quickly switching the on-off state of a switch connected to the dimmable lamp.

In the related art, a dimmable light fixture includes: the light-emitting module and the isolation power circuit. The isolation power circuit is respectively connected with a power end and the light-emitting module, and the power end is connected with a power supply through a switch. After the switch is closed, the power supply end can provide a power supply signal from a power supply source for the isolation power supply circuit, and the isolation power supply circuit can further drive the light-emitting module to emit light. Moreover, in order to realize the adjustment of the light emitting parameters, the dimmable light fixture further comprises: the dimming circuit is connected with the power supply end, can determine the on-off state of the switch by detecting a power supply signal, and can adjust the light-emitting parameters of the light-emitting module when the on-off state of the switch is detected to be rapidly switched. Since the power signal is a strong electric signal, an isolation element (e.g., an optocoupler) is also required between the dimming circuit and the power supply terminal in order to ensure the operational safety of the detection circuit.

However, since the isolation element belongs to the safety element and needs to maintain a certain safety distance with other circuits during the setting, the area of the circuit board for setting each circuit in the dimmable lamp is large, which is not favorable for the miniaturization design of the LED lamp.

Disclosure of Invention

The embodiment of the application provides a power supply circuit and a lamp, is favorable to the miniaturized design of lamps and lanterns, technical scheme is as follows:

in one aspect, an embodiment of the present application provides a power supply circuit, where the power supply circuit includes: the primary switch circuit, the secondary rectifier circuit and the dimming circuit;

the input end of the primary switch circuit is used for being connected with a switch, the switch is also connected with a power supply, the output end of the primary switch circuit is connected with the input end of the secondary rectification circuit, and the primary switch circuit is used for converting a power supply signal provided by the power supply into an alternating current driving signal and outputting the alternating current driving signal to the secondary rectification circuit after the switch is closed;

the output end of the secondary rectifying circuit is used for being connected with the input end of the light-emitting module, and the secondary rectifying circuit is used for converting the alternating current driving signal into a direct current driving signal and outputting the direct current driving signal to the light-emitting module;

the input end of the dimming circuit is connected with the input end of the secondary rectifying circuit, the output end of the dimming circuit is used for being connected with the control end of the light-emitting module, the dimming circuit is used for detecting a signal of the input end of the secondary rectifying circuit, determining the on-off state of the switch according to the signal of the input end of the secondary rectifying circuit, and outputting a dimming control signal to the light-emitting module if the on-off state meets a dimming condition, wherein the dimming control signal is used for adjusting light-emitting parameters of the light-emitting module.

In one possible design, the dimming circuit includes: a filter sub-circuit and a dimming sub-circuit;

the input end of the filter sub-circuit is used as the input end of the dimming circuit and is connected with the input end of the secondary rectifying circuit, the output end of the filter sub-circuit is connected with the input end of the dimming sub-circuit, and the filter sub-circuit is used for filtering the signal at the input end of the secondary rectifying circuit and outputting the filtered signal to the dimming sub-circuit;

the output end of the dimming sub-circuit is used as the output end of the dimming circuit and connected with the control end of the light-emitting module, the dimming sub-circuit is used for detecting the filtered signal, determining the on-off state of the switch according to the filtered signal, and outputting the dimming control signal to the light-emitting module if the on-off state meets the dimming condition.

In one possible design, the photon modulation circuit is configured to determine that the on-off state of the switch is a closed state if it is detected that the filtered signal satisfies a first target condition, and determine that the on-off state of the switch is an open state if it is detected that the level of the filtered signal satisfies a second target condition; wherein the first target condition is: the filtered signal is a square wave signal, the duration of the square wave signal at a first level in one period is greater than or equal to a first duration threshold, and the duration of the square wave signal at a second level is less than or equal to a second duration threshold; the second target condition is: the time length of the filtered signal at the second level is greater than or equal to a third time length threshold, the first level is a high level relative to the second level, the third time length threshold is greater than the second time length threshold, and the second time length threshold is greater than the first time length threshold.

In one possible design, the dimming sub-circuit includes: a sampler, an arithmetic unit and a central processing unit;

the input interface of the sampler is used as the input end of the dimming sub-circuit and is connected with the output end of the filtering sub-circuit, and the sampler is used for receiving the filtered signal and providing the filtered signal to the arithmetic unit;

the arithmetic unit is used for detecting the signal parameters of the filtered signals and providing the detected signal parameters to the central processing unit;

the output interface of the central processing unit is used as the output end of the dimming sub-circuit and connected with the control end of the light-emitting module, and the central processing unit is used for determining the on-off state of the switch based on the signal parameters and outputting the dimming control signal to the light-emitting module if the on-off state is determined to meet the dimming condition.

In one possible design, the filtering sub-circuit includes: a first resistor and a first capacitor;

one end of the first resistor and one end of the first capacitor are used as the input end of the filter sub-circuit and connected with the input end of the secondary rectification circuit, and the other end of the first resistor and the other end of the first capacitor are used as the output end of the filter sub-circuit and connected with the input end of the dimming sub-circuit.

In one possible design, the dimming condition is: and in the target duration, the on-off state of the switch is switched from the on state to the off state and then switched from the off state to the on state, and the target duration is less than the duration threshold.

In one possible design, the primary switching circuit includes: a primary switching sub-circuit and an isolation transformer;

the input end of the primary switch sub-circuit is used as the input end of the primary switch circuit and is used for being connected with the switch, the output end of the primary switch sub-circuit is connected with the input end of the isolation transformer, and the primary switch sub-circuit is used for converting a power supply signal provided by the power supply into an initial alternating current signal after the switch is closed and outputting the initial alternating current signal to the isolation transformer;

the output end of the isolation transformer is used as the output end of the primary switch circuit and is connected with the input end of the secondary rectification circuit, and the isolation transformer is used for carrying out frequency conversion on the initial alternating current signal to obtain the alternating current driving signal and outputting the alternating current driving signal to the secondary rectification circuit.

In one possible design, the power supply circuit further includes: a rectification filter circuit;

the input end of the rectification filter circuit is used for being connected with the switch, the output end of the rectification filter circuit is connected with the input end of the primary switch circuit, and the rectification filter circuit is used for rectifying and filtering the power supply signal after the switch is closed and outputting the rectified and filtered power supply signal to the primary switch circuit.

In one possible design, the primary switching circuit includes: a primary switching sub-circuit and an isolation transformer; the rectification filter circuit includes: the circuit comprises a safety device, a rectifier bridge, an inductor, a second capacitor and a third capacitor; the primary switching sub-circuit comprises: the circuit comprises an inductance coil, a first diode, a fourth capacitor, a first transistor, a second transistor and a switching power supply unit; the secondary rectification circuit includes: the second diode, the fifth capacitor and the second resistor;

the input end of the rectifier bridge is used as the input end of the rectifier filter circuit and is used for being connected with the switch, the first output end of the rectifier bridge is respectively connected with one end of the inductor and one end of the second capacitor, the second output end of the rectifier bridge is connected with a first grounding end, the other end of the inductor and one end of the third capacitor are used as the output end of the rectifier filter circuit and are connected with the input end of the inductance coil, the other end of the second capacitor and the other end of the third capacitor are both connected with the first grounding end, and the input end of the inductance coil is the input end of the primary switch sub-circuit;

the output end of the inductance coil is respectively connected with the second pole of the first transistor and the first pole of the first diode, the second pole of the first diode and one end of the fourth capacitor are used as the first output end of the primary switch sub-circuit to be connected with the input end of the isolation transformer, the other end of the fourth capacitor is connected with the first grounding end, the grid electrode and the first pole of the first transistor and the grid electrode and the first pole of the second transistor are both connected with the switching power supply unit, and the second pole of the second transistor is used as the second output end of the primary switch sub-circuit to be connected with the input end of the isolation transformer;

the output end of the isolation transformer is connected with the first pole of the second diode, the second pole of the second diode, one end of the fifth capacitor and one end of the second resistor are used as the output end of the secondary rectification circuit and connected with the input end of the light-emitting module, the other end of the fifth capacitor and the other end of the second resistor are connected with the second grounding end, and the first pole of the second diode is the input end of the secondary rectification circuit.

In another aspect, an embodiment of the present application provides a lamp, where the lamp includes: the light emitting module comprises a light emitting module and a power circuit which is connected with the light emitting module and provided in any one of the possible designs.

In one possible design, the light emitting module includes: at least one switching transistor and a plurality of light emitting components, each of the light emitting components comprising a plurality of light emitting diodes connected in series;

each switch transistor is connected with at least one light-emitting component in series, and the light-emitting components connected with the switch transistors are different;

and the grid electrode of each switching transistor is used as the control end of the light-emitting module and is connected with the output end of a dimming circuit included by the power supply circuit.

The technical scheme provided by the embodiment of the application has the beneficial effects that at least:

the embodiment of the application provides a power supply circuit and a lamp, wherein a dimming circuit in the power supply circuit is connected with an input end of a secondary rectification circuit, and the on-off state of a switch can be determined by directly detecting a signal at the input end of the secondary rectification circuit. Because the signal at the input end of the secondary rectification circuit belongs to a weak current signal relative to the power supply signal, an isolation element does not need to be additionally arranged between the dimming circuit and the input end of the secondary rectification circuit to ensure the working safety of the dimming circuit, and the design of the power supply circuit is beneficial to realizing the miniaturization of the lamp.

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 description of the embodiments are briefly introduced 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 be able to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a power supply circuit provided in an embodiment of the present application;

FIG. 2 is a waveform diagram illustrating simulation of an AC driving signal according to an embodiment of the present application;

FIG. 3 is a schematic diagram of another power circuit according to an embodiment of the present disclosure;

FIG. 4 is a timing diagram of an AC driving signal according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a dimming sub-circuit according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a structure of another power circuit provided in an embodiment of the present application;

FIG. 7 is a schematic diagram of a power supply circuit according to an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of another power circuit provided in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a lamp provided in the embodiment of the present application;

fig. 10 is a schematic structural diagram of another lamp provided in the embodiment of the present application.

The various reference numbers in the drawings are illustrated below:

000-power circuit, 001-switch, 002-power supply and 003-light emitting module;

10-a primary switching circuit, 20-a secondary rectifying circuit, 30-a dimming circuit and 40-a rectifying and filtering circuit;

101-primary switch sub-circuit, 102-isolation transformer;

301-a filter sub-circuit, 302-a dimming sub-circuit;

3021-sampler, 3022-arithmetic unit, CPU-CPU, R1-first resistor, R2-second resistor, C1-first capacitor, C2-second capacitor, C3-third capacitor, C4-fourth capacitor, C5-fifth capacitor, L1-inductor, T1-inductor, D1-first diode, D2-second diode, Q1-first transistor, Q2-second transistor, F1-fuse, BD 1-rectifier bridge, 1011-switching power supply, GND-first ground, PGND-second ground, M0-switching transistor, L0-light emitting device, and L01-light emitting diode.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

As can be seen from the description of the background art, in the related art, an isolation element needs to be additionally disposed between the dimming circuit and the power source end connected to the dimming circuit, so that the area of a Printed Circuit Board (PCB) for disposing each circuit in the dimmable lamp is large, which is not favorable for miniaturization and compact design of the lamp. The embodiment of the application provides a power supply circuit, which can realize the miniaturization and compact design of a lamp on the basis of not influencing the on-off state of a determined switch and adjusting the light-emitting parameters of the lamp based on the on-off state of the switch. Alternative designs of the power supply circuit may be described with reference to the following embodiments:

fig. 1 is a schematic structural diagram of a power supply circuit according to an embodiment of the present disclosure. As shown in fig. 1, the power supply circuit 000 includes: a primary switching circuit 10, a secondary rectifier circuit 20 and a dimming circuit 30.

The input end of the primary switch circuit 10 is used for being connected with a switch 001, the switch 001 is further connected with a power supply 002, and the output end of the primary switch circuit 10 is connected with the input end of the secondary rectification circuit 20. The primary switching circuit 10 can be configured to convert a power supply signal supplied from the power supply 002 into an ac drive signal and output the ac drive signal to the secondary rectifier circuit 20 after the switch 001 is closed.

That is, referring to fig. 1, the switch 001 is connected between the power supply source 002 and the primary switching circuit 10, and is dedicated to controlling the power supply source 002 and the primary switching circuit 10 to be connected or disconnected. After the switch 001 is closed, the power supply 002 is connected to the primary switch circuit 10, and the power signal provided by the power supply 002 can be transmitted to the primary switch circuit 10 through the switch 001, so that the primary switch circuit 10 can perform conversion processing on the power signal. In contrast, after the switch 001 is turned off, the power supply source 002 and the primary switch circuit 10 are turned off, i.e., in a non-connected state, and thus, the power supply signal provided by the power supply source 002 cannot be transmitted to the primary switch circuit 10 through the switch 001.

Alternatively, the on-off state of switch 001 (i.e., when switch 001 is closed and when it is open) may be controlled by the user. And the switch 001 may be any type of switch, for example, a push button switch or a rotary switch mounted on a wall for use with a wall lamp (i.e., a wall-mounted lamp).

Optionally, the power signal provided by the power supply 002 may be 220V mains, and the potential of the ac driving signal converted by the primary switch circuit 10 from the power signal is smaller than the potential of the power signal, that is, the power signal is a strong current signal, and the ac driving signal is a weak current signal. And the ac driving signal may be a square wave signal, and the frequency of the ac driving signal may be the same as the operating frequency of the primary switching circuit 10.

The output end of the secondary rectification circuit 20 is used for being connected with the input end of the light-emitting module 003. The secondary rectification circuit 20 is configured to convert the ac driving signal into a dc driving signal, and output the dc driving signal to the light emitting module 003. The dc driving signal can be used to drive the light emitting module 003 to emit light, that is, the light emitting module 003 can emit light in response to the dc driving signal.

As can be seen from the above description of the isolated power supply circuit, in the power supply circuit provided in the embodiment of the present application, the whole of the primary switch circuit 10 and the secondary rectifier circuit 20 is the isolated power supply circuit.

The input end of the dimming circuit 30 is connected to the input end of the secondary rectification circuit 20, and the output end of the dimming circuit 30 is used for being connected to the control end of the light emitting module 003. The dimming circuit 30 is configured to detect a signal at an input terminal of the secondary rectification circuit 20, determine an on/off state of the switch 001 according to the signal at the input terminal of the secondary rectification circuit 20, and output a dimming control signal to the light emitting module 003 if it is determined that the on/off state satisfies a dimming condition. The dimming control signal can be used to adjust the lighting parameter of the lighting module 003, that is, the lighting parameter of the lighting module 003 is affected by the lighting control signal. Alternatively, the light emission parameter may include at least one of a light emission luminance and a light emission chromaticity.

Since the input terminal of the secondary rectification circuit 20 receives the ac driving signal after the switch 001 is closed, and the input terminal of the secondary rectification circuit 20 does not receive any signal after the switch 001 is opened, that is, the input terminal of the secondary rectification circuit 20 may be at an invalid level of 0V, the dimming circuit 30 can reliably determine the on/off state of the switch 001 by detecting the signal at the input terminal of the secondary rectification circuit 20.

In the embodiment of the present application, the dimming condition can be preset in the dimming circuit 30, and the dimming condition can be: within a target time length, the on-off state of the switch 001 is switched from the on state to the off state, and then switched from the off state to the on state, where the target time length is less than a time length threshold, for example, the time length threshold may be 10 seconds. That is, the dimming circuit 30 can determine that the dimming condition is satisfied when detecting that the on-off state of the switch 001 is rapidly switched.

It is assumed that the input terminal of the primary switching circuit 10 is referred to as a preceding stage, and the output terminal of the primary switching circuit 10 (i.e., the input terminal of the secondary rectifier circuit 20) is referred to as a secondary stage. It can be determined that: in the related art, the detection circuit detects a signal at a front stage to determine the on/off state of the switch 001, where the signal at the front stage is a power supply signal and the power supply signal is a strong electric signal. In the embodiment of the present application, the dimming circuit 30 determines the on/off state of the switch 001 by detecting a signal at the secondary stage, where the signal is an ac driving signal, and the ac driving signal is a weak current signal relative to the power signal. Because the strong electric signal can lead to detection circuitry to be damaged, and the weak electric signal can not lead to dimming circuit generally to be damaged, consequently relevant technique needs additionally to set up isolation element, and this application embodiment need not additionally to set up isolation element and can reliably confirm the on-off state of switch 001, has reached the detection effect the same with relevant technique, is favorable to miniaturized design.

In summary, the embodiments of the present application provide a power supply circuit, a dimming circuit in the power supply circuit is connected to an input end of a secondary rectification circuit, and can determine an on-off state of a switch by directly detecting a signal at the input end of the secondary rectification circuit. Because the signal at the input end of the secondary rectification circuit belongs to a weak current signal relative to the power supply signal, an isolation element does not need to be additionally arranged between the dimming circuit and the input end of the secondary rectification circuit to ensure the working safety of the dimming circuit, and the design of the power supply circuit is beneficial to realizing the miniaturization of the lamp.

Fig. 2 shows a simulated waveform diagram of an ac drive signal. Where the horizontal axis represents time in microseconds (μ s) and the vertical axis represents voltage in V.

Fig. 3 is a schematic structural diagram of another power supply circuit provided in an embodiment of the present application. As shown in fig. 3, the dimming circuit 30 may include: a filtering sub-circuit 301 and a dimming sub-circuit 302.

An input of the filter sub-circuit 301 may be connected as an input of the dimming circuit 30 to an input of the secondary rectification circuit 20, and an output of the filter sub-circuit 301 is connected to an input of the dimming sub-circuit 302. The filtering sub-circuit 301 may be configured to filter a signal at an input of the secondary rectification circuit 20 and output the filtered signal to the dimming sub-circuit 302.

The output terminal of the dimming sub-circuit 302 can be connected as the output terminal of the dimming circuit 30 to the control terminal of the light emitting module 003 (not shown in fig. 3). The dimming sub-circuit 302 may be configured to detect the filtered signal, determine an on-off state of the switch 001 according to the filtered signal, and output a dimming control signal to the light emitting module 003 if it is determined that the on-off state satisfies the dimming condition.

By arranging the filter sub-circuit 301, the interference of other signals to the signals at the input end of the secondary rectification circuit 20 can be filtered, the precision of the signals received by the light modulation sub-circuit 302 is ensured, and then the reliability of the light modulation sub-circuit 302 for determining the on-off state of the switch 001 based on the signals at the input end of the secondary rectification circuit 20 after filtering processing can be ensured, and finally, the light modulation control signal is output to the light emitting module 003 based on the on-off state of the switch 001, so that the reliability of the light emitting parameters of the light emitting module 003 can be adjusted.

Optionally, the dimming sub-circuit 302 is configured to determine that the on-off state of the switch is the closed state if it is detected that the filtered signal satisfies the first target condition. And if the level of the signal after the filtering processing is detected to meet a second target condition, determining the on-off state of the switch to be an off state.

Optionally, the first target condition is: the signal after filtering processing is a square wave signal, the duration of the square wave signal at the first level in one period is greater than or equal to a first duration threshold, and the duration of the square wave signal at the second level is less than or equal to a second duration threshold. The second target condition is: and the time length of the filtered signal at the second level is greater than or equal to a third time length threshold value.

The first level may be a high level relative to the second level, the third duration threshold is greater than the second duration threshold, and the second duration threshold is greater than the first duration threshold. The amplitude of the first level may be greater than a first amplitude threshold, the amplitude of the second level may be less than a second amplitude threshold, and in order to reliably determine the on-off state of the switch 001, the dimming sub-circuit 302 may determine that the filtered signal satisfies the first target condition when it is detected that the square wave signal continuously satisfies the first target condition for two or more cycles.

For example, the first duration threshold may be 2 μ s, the second duration threshold may be 100 μ s, the third duration threshold may be 120 μ s, the first magnitude threshold may be 1V, and the second magnitude threshold may be 0.2V. That is, in conjunction with the waveform diagram of the square wave signal shown in fig. 4, the dimming sub-circuit 302 can determine that the on-off state of the switch 001 is the closed state when detecting that the duration t1 of the square wave signal at the first level in one period is greater than or equal to 2 μ s, the duration t2 of the square wave signal at the second level is less than or equal to 100 μ s, and detecting that the square wave signal satisfies the above state in more than two periods. And the dimming sub-circuit 302 can determine that the on-off state of the switch 001 is the off state when it is detected that the duration of the filtered signal at the second level is less than or equal to 120 μ s and the amplitude of the second level is less than 0.2V.

Optionally, fig. 5 is a schematic structural diagram of a dimming sub-circuit according to an embodiment of the present invention. As shown in fig. 5, the dimming sub-circuit 302 includes: a sampler 3021, an operator 3022, and a Central Processing Unit (CPU).

An input interface of sampler 3021 may be connected as an input of dimming sub-circuit 302 to an output of filtering sub-circuit 301 (not shown in fig. 5). The sampler 3021 may be configured to receive the filtered signal and provide the filtered signal to an operator 3022.

The operator 3022 is configured to detect a signal parameter of the filtered signal and supply the detected signal parameter to the central processing unit CPU.

Wherein the signal parameters may comprise at least one of the following parameters: the waveform of the signal (e.g., the type of waveform), the amplitude of the signal (e.g., the amplitude of the signal at a high level and the amplitude of the signal at a low level when the signal is a square wave), the frequency and duration of the signal (e.g., the duration of the signal at a high level and the duration of the signal at a low level during one cycle). Accordingly, in order to detect the signal parameter, the operator 3022 may generally include a comparator, a timer, and the like.

The output interface of the central processing unit CPU can be connected as the output terminal of the dimming sub-circuit 302 to the control terminal of the light emitting module 003 (not shown in fig. 5). The central processing unit CPU can be configured to determine the on-off state of the switch 001 based on the signal parameter, and output a dimming control signal to the light emitting module 003 if it is determined that the on-off state satisfies the dimming condition.

As can be seen from the above description of the embodiment that the photon conditioning circuit 302 determines the on-off state of the switch 001 based on the filtered signal, the central processing unit CPU may preset a first target condition and a second target condition. Assume that the signal parameters provided by the operator 3022 are: the waveform is a square wave, and the duration of the square wave signal at the first level (i.e., high level) in one period is greater than or equal to the first duration threshold, and the duration of the square wave signal at the second level (i.e., low level) is less than or equal to the second duration threshold, that is, the first target condition is met, then the central processing unit CPU may determine that the switch 001 is in the closed state at this time. Similarly, assume that the signal parameters provided by the operator 3022 are: if the time length of the signal at the second level is greater than or equal to the third time length threshold, that is, the second target condition is met, the central processing unit CPU may determine that the switch 001 is in the off state at this time.

It should be noted that sampler 3021, arithmetic unit 3022, and central processing unit CPU may be three independent devices; alternatively, the sampler 3021, the arithmetic unit 3022 and the central processing unit CPU may be integrated, for example, all integrated into a single chip, and accordingly, the dimming sub-circuit 302 is a single chip.

Fig. 6 is a schematic structural diagram of another power supply circuit provided in the embodiment of the present application. As shown in fig. 6, the primary switching circuit 10 may include: a primary switching sub-circuit 101 and an isolation transformer 102.

An input of the primary switch sub-circuit 101 may be used as an input of the primary switch circuit 10 for connection to a switch 001 (not shown in fig. 6), and an output of the primary switch sub-circuit 101 is connected to an input of the isolation transformer 102. The primary switch sub-circuit 101 can be configured to convert a power signal provided by the power supply 002 into an initial ac signal and output the initial ac signal to the isolation transformer 102 after the switch 001 is closed.

An output terminal of the isolation transformer 102 may be connected as an output terminal of the primary switching circuit 10 to an input terminal of the secondary rectification circuit 20. The isolation transformer 102 can be used to perform frequency conversion on the initial ac signal to obtain an ac driving signal, and output the ac driving signal to the secondary rectification circuit 20.

Fig. 7 is a schematic structural diagram of another power supply circuit provided in an embodiment of the present application. As shown in fig. 7, the power supply circuit may further include: and a rectifying and filtering circuit 40.

The input of the rectifying and smoothing circuit 40 is used for connecting to a switch 001 (not shown in fig. 7), and the output of the rectifying and smoothing circuit 40 is connected to the input of the primary switching circuit 10. The rectifying-filtering circuit 40 can be configured to rectify and filter the power signal after the switch 001 is closed, and output the rectified and filtered power signal to the primary switching circuit 10.

By providing the rectifying and filtering circuit 40, interference of other signals to the power supply signal provided by the power supply 002 can be filtered out, and the accuracy of the power supply signal received by the primary switch sub-circuit 101 is ensured, so that the accuracy of the alternating current driving signal converted from the power supply signal by the primary switch sub-circuit 101 can be ensured. Further, the reliability of the dimming circuit 30 in determining the on-off state of the switch 001 and the reliability in outputting the dimming control signal to the light emitting module 003 based on the on-off state of the switch 001 are ensured.

Fig. 8 is a schematic structural diagram of another power supply circuit provided in an embodiment of the present application. As shown in fig. 8, the filtering sub-circuit 301 may include: a first resistor R1 and a first capacitor C1.

One end of the first resistor R1 and one end of the first capacitor C1 may be connected to the input terminal of the secondary rectification circuit 20 as the input terminal of the filter sub-circuit 301. The other end of the first resistor R1 and the other end of the first capacitor C1 may be connected as an output terminal of the filtering sub-circuit 301 to an input terminal of the dimming sub-circuit 302.

The primary switching circuit 10 may include: a primary switching sub-circuit 101 and an isolation transformer 102. The rectifying and filtering circuit 40 may include: fuse F1, rectifier bridge BD1, inductance L1, second electric capacity C2 and third electric capacity C3. The primary switch sub-circuit 101 may include: an inductor T1, a first diode D1, a fourth capacitor C4, a first transistor Q1, a second transistor Q2 and a switching power supply unit 1011. The secondary rectifier circuit 20 may include: a second diode D2, a fifth capacitor C5, and a second resistor R2.

An input end of the rectifier bridge BD1 may serve as an input end of the rectifier and filter circuit 40 and is configured to be connected to the switch 001 (not shown in fig. 8), a first output end of the rectifier bridge BD1 may be connected to one end of the inductor L1 and one end of the second capacitor C2, a second output end of the rectifier bridge BD1 may be connected to the first ground GND, another end of the inductor L1 and one end of the third capacitor C3 may serve as an output end of the rectifier and filter circuit 40 and be connected to an input end of the inductor T1, another end of the second capacitor C2 and another end of the third capacitor C3 are both connected to the first ground GND, where the input end of the inductor T1 is the input end of the primary switch sub-circuit 101.

An output terminal of the inductor T1 is connected to a second terminal of the first transistor Q1 and a first terminal of the first diode D1, respectively, a second terminal of the first diode D1 and one terminal of the fourth capacitor C4 may be connected to an input terminal of the isolation transformer 102 as a first output terminal of the primary switch sub-circuit 101, the other terminal of the fourth capacitor C4 is connected to the first ground terminal GND, a gate and a first terminal of the first transistor Q1, and a gate and a first terminal of the second transistor Q2 are connected to the switching power supply unit 1011, and a second terminal of the second transistor Q2 may be connected to an input terminal of the isolation transformer 102 as a second output terminal of the primary switch sub-circuit 101.

An output terminal of the isolation transformer 102 is connected to a first pole of the second diode D2, a second pole of the second diode D2, one end of the fifth capacitor C5, and one end of the second resistor R2 may be connected to an input terminal of the light emitting module 003 as an output terminal of the secondary rectification circuit 20 (not shown in fig. 8), and the other end of the fifth capacitor C5 and the other end of the second resistor R2 are both connected to a second ground terminal PGND, where a first pole of the second diode D2 is an input terminal of the secondary rectification circuit 20.

Optionally, the first pole of the diode is an anode and the second pole is a cathode. The isolation transformer 102 is an inductor. The first capacitor C1, the second capacitor C2 and the third capacitor C3 are all common storage capacitors, and the fourth capacitor C4 and the fifth capacitor C5 are all electrolytic capacitors with large capacity.

Fig. 9 is a schematic structural diagram of a lamp provided in the embodiment of the present application. As shown in fig. 9, the lamp includes: a light emitting module 003, and a power circuit 000 as shown in any one of fig. 1, 3, and 6 to 8 connected to the light emitting module 003. The light emitting module 003 can emit light under the control of the power circuit 000.

Optionally, the light emitting module 003 includes: at least one switching transistor and a plurality of light emitting components, each light emitting component comprising a plurality of light emitting diodes connected in series.

Wherein each switching transistor may be connected in series with at least one light emitting element, and the light emitting elements to which the respective switching transistors are connected are different. The gate of each switching transistor may be connected as a control terminal of the light emitting module 003 to the output terminal of the dimming circuit 30 included in the power supply circuit 000.

For example, referring to fig. 10, a light emitting module 003 including 2 light emitting devices L0 and 2 switching transistors M0 is shown, wherein each light emitting device L0 includes a plurality of light emitting diodes L01 connected in series. And fig. 10 also shows, in conjunction with fig. 8, an internal optional circuit configuration of the power supply circuit 000, a switch 001 to which the power supply circuit 000 is connected, and a power supply source 002 to which the switch 001 is connected.

With reference to fig. 10, the following description is made on the working principle of the entire lamp provided by the embodiment of the present application:

after the switch is closed 001, the power supply 002 supplies the power signal to the rectifying and filtering circuit 40 through the switch 001, and the rectifying and filtering circuit 40 performs rectifying and filtering processing on the power signal and further outputs the rectified and filtered signal to the input end of the inductance coil T1. The first transistor Q1 is turned on under the control of the signal of the first potential provided by the switching power supply unit 1011, and at this time, the current on the inductor T1 starts to rise, and the inductor T1 stores energy. When the current in the inductor T1 rises to the set value, the switching power supply unit 1011 provides the first transistor Q1 with a signal of the second potential, the first transistor Q1 is turned off, and at this time, the inductor T1 starts to release the energy stored in the previous energy storage, so that the first diode D1 is turned on. Then, the discharged energy may be output to the fourth capacitor C4, the isolation transformer T2, and the second transistor Q1 through the first diode D1, charge the fourth capacitor C4, and supply energy to the isolation transformer T2 and the second transistor Q1. When the energy of the inductor T1 is released, the switching power supply unit 1011 can control the first transistor Q1 to conduct again, and the above operation is performed cyclically.

The switching power supply unit 1011 may also output a signal of the first potential to the gate of the second transistor Q2 to control the second transistor Q2 to be turned on. At this time, the current on the primary winding of isolation transformer 102 begins to rise, and isolation transformer 102 begins to store energy. As with the first transistor Q1, the current on the primary winding of the isolation transformer 102 rises to the set value, the switching power supply unit 1011 provides a signal at the second potential to the second transistor Q2, and the second transistor Q2 is turned off. At this time, the primary coil of the isolation transformer 102 starts transferring the previously stored energy to the secondary coil, so that the second diode D2 is turned on. Then, the energy released by the isolation transformer 102 can be output to the fifth capacitor C5 and the light emitting module 003 through the second diode D2, so as to charge the fifth capacitor C5 and supply power to the light emitting module 003, and the light emitting module 003 emits light. After the isolation transformer 102 releases energy, the switching power supply unit 1011 can control the second transistor Q2 to conduct again, and perform the above operation in a cycle, so as to achieve the effect of saving energy.

The signal at the first pole of the second diode D2 may be filtered by the first resistor R1 and the first capacitor C1 and then output to the dimming sub-circuit 302, so that the dimming sub-circuit 302 may detect the filtered signal and determine the on-off state of the switch 001 based on the detection result. When it is determined that the switch 001 is closed and it is determined that the dimming condition is satisfied, the dimming sub-circuit 302 may output the dimming control signal to the two switching transistors M0, thereby implementing adjustment of the light emitting parameters of the light emitting diodes L01.

Alternatively, each of the transistors described in the above embodiments of the present application may be an N-type transistor, and accordingly, the first potential may be a low potential relative to the second potential. Of course, each transistor may also be a P-type transistor, and when each transistor is a P-type transistor, the first potential is a high potential relative to the second potential.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A power supply circuit, characterized in that the power supply circuit comprises: a primary switching circuit (10), a secondary rectification circuit (20) and a dimming circuit (30);

the input end of the primary switch circuit (10) is used for being connected with a switch (001), the switch (001) is also connected with a power supply (002), the output end of the primary switch circuit (10) is connected with the input end of the secondary rectification circuit (20), and the primary switch circuit (10) is used for converting a power supply signal provided by the power supply (002) into an alternating current driving signal and outputting the alternating current driving signal to the secondary rectification circuit (20) after the switch (001) is closed;

the output end of the secondary rectifying circuit (20) is used for being connected with the input end of the light-emitting module (003), and the secondary rectifying circuit (20) is used for converting the alternating current driving signal into a direct current driving signal and outputting the direct current driving signal to the light-emitting module (003);

the input end of the dimming circuit (30) is connected with the input end of the secondary rectifying circuit (20), the output end of the dimming circuit (30) is used for being connected with the control end of the light-emitting module (003), the dimming circuit (30) is used for detecting a signal of the input end of the secondary rectifying circuit (20), the on-off state of the switch (001) is determined according to the signal of the input end of the secondary rectifying circuit (20), and if the on-off state meets a dimming condition, a dimming control signal is output to the light-emitting module (003), and the dimming control signal is used for adjusting light-emitting parameters of the light-emitting module (003).

2. The power supply circuit according to claim 1, wherein the dimming circuit (30) comprises: a filtering sub-circuit (301) and a dimming sub-circuit (302);

an input end of the filter sub-circuit (301) is connected to an input end of the secondary rectification circuit (20) as an input end of the dimming circuit (30), an output end of the filter sub-circuit (301) is connected to an input end of the dimming sub-circuit (302), and the filter sub-circuit (301) is configured to filter a signal at the input end of the secondary rectification circuit (20) and output the filtered signal to the dimming sub-circuit (302);

the output end of the dimming sub-circuit (302) is used as the output end of the dimming circuit (30) and is connected with the control end of the light-emitting module (003), the dimming sub-circuit (302) is used for detecting the signal after filtering processing, determining the on-off state of the switch (001) according to the signal after filtering processing, and outputting the dimming control signal to the light-emitting module (003) if the on-off state meets the dimming condition.

3. The power supply circuit according to claim 2, wherein the photonic tuning circuit (302) is configured to determine the on-off state of the switch as a closed state if it is detected that the filtered signal satisfies a first target condition, and to determine the on-off state of the switch as an open state if it is detected that the level of the filtered signal satisfies a second target condition;

wherein the first target condition is: the filtered signal is a square wave signal, the duration of the square wave signal at a first level in one period is greater than or equal to a first duration threshold, and the duration of the square wave signal at a second level is less than or equal to a second duration threshold; the second target condition is: the time length of the filtered signal at the second level is greater than or equal to a third time length threshold, the first level is a high level relative to the second level, the third time length threshold is greater than the second time length threshold, and the second time length threshold is greater than the first time length threshold.

4. The power supply circuit of claim 2, wherein the photonic tuning circuit (302) comprises: a sampler (3021), an arithmetic unit (3022), and a Central Processing Unit (CPU);

an input interface of the sampler (3021) is connected as an input of the dimming sub-circuit (302) to an output of the filtering sub-circuit (301), and the sampler (3021) is configured to receive the filtered signal and provide the filtered signal to the operator (3022);

the arithmetic unit (3022) is configured to detect a signal parameter of the filtered signal and provide the detected signal parameter to the Central Processing Unit (CPU);

an output interface of the Central Processing Unit (CPU) is used as an output end of the dimming sub-circuit (302) and connected with a control end of the light-emitting module (003), and the Central Processing Unit (CPU) is used for determining the on-off state of the switch (001) based on the signal parameters and outputting the dimming control signal to the light-emitting module (003) if the on-off state is determined to meet the dimming condition.

5. The power supply circuit according to claim 2, wherein the filter sub-circuit (301) comprises: a first resistor (R1) and a first capacitor (C1);

one end of the first resistor (R1) and one end of the first capacitor (C1) are connected with the input end of the secondary rectifying circuit (20) as the input end of the filter sub-circuit (301), and the other end of the first resistor (R1) and the other end of the first capacitor (C1) are connected with the input end of the dimming sub-circuit (302) as the output end of the filter sub-circuit (301).

6. The power supply circuit according to any one of claims 1 to 5, wherein the dimming condition is: and in the target duration, the on-off state of the switch (001) is switched from the on state to the off state and then switched from the off state to the on state, and the target duration is less than the duration threshold.

7. The power supply circuit according to any one of claims 1 to 5, wherein the primary switching circuit (10) comprises: a primary switch sub-circuit (101) and an isolation transformer (102);

the input end of the primary switch sub-circuit (101) is used as the input end of the primary switch circuit (10) and is used for being connected with the switch (001), the output end of the primary switch sub-circuit (101) is connected with the input end of the isolation transformer (102), and the primary switch sub-circuit (101) is used for converting a power supply signal provided by the power supply (002) into an initial alternating current signal and outputting the initial alternating current signal to the isolation transformer (102) after the switch (001) is closed;

the output end of the isolation transformer (102) is used as the output end of the primary switch circuit (10) and is connected with the input end of the secondary rectification circuit (20), and the isolation transformer (102) is used for carrying out frequency conversion on the initial alternating current signal to obtain the alternating current driving signal and outputting the alternating current driving signal to the secondary rectification circuit (20).

8. The power supply circuit according to any one of claims 1 to 5, characterized in that the power supply circuit further comprises: a rectifying-filtering circuit (40);

the input end of the rectifying and filtering circuit (40) is used for being connected with the switch (001), the output end of the rectifying and filtering circuit (40) is connected with the input end of the primary switch circuit (10), and the rectifying and filtering circuit (40) is used for rectifying and filtering the power supply signal after the switch (001) is closed and outputting the rectified and filtered power supply signal to the primary switch circuit (10).

9. The power supply circuit according to claim 8, wherein the primary switching circuit (10) comprises: a primary switch sub-circuit (101) and an isolation transformer (102); the rectifying-filtering circuit (40) includes: the circuit comprises a fuse device (F1), a rectifier bridge (BD1), an inductor (L1), a second capacitor (C2) and a third capacitor (C3); the primary switching sub-circuit (101) comprises: an inductance coil (T1), a first diode (D1), a fourth capacitor (C4), a first transistor (Q1), a second transistor (Q2) and a switching power supply unit (1011); the secondary rectifier circuit (20) comprises: a second diode (D2), a fifth capacitor (C5), and a second resistor (R2);

an input end of the rectifier bridge (BD1) is used as an input end of the rectifier filter circuit (40) and is connected to the switch (001), a first output end of the rectifier bridge (BD1) is respectively connected to one end of the inductor (L1) and one end of the second capacitor (C2), a second output end of the rectifier bridge (BD1) is connected to a first ground end (GND), the other end of the inductor (L1) and one end of the third capacitor (C3) are used as output ends of the rectifier filter circuit (40) and are connected to an input end of the inductor coil (T1), the other end of the second capacitor (C2) and the other end of the third capacitor (C3) are both connected to the first ground end (GND), and an input end of the inductor coil (T1) is an input end of the primary switch sub-circuit (101);

the output end of the inductor (T1) is connected with the second pole of the first transistor (Q1) and the first pole of the first diode (D1), respectively, the second pole of the first diode (D1) and one end of the fourth capacitor (C4) are connected as the first output end of the primary switch sub-circuit (101) and the input end of the isolation transformer (102), the other end of the fourth capacitor (C4) is connected with the first ground end (GND), the gate and the first pole of the first transistor (Q1), and the gate and the first pole of the second transistor (Q2) are both connected with the switching power supply unit (1011), and the second pole of the second transistor (Q2) is connected as the second output end of the primary switch sub-circuit (101) and the input end of the isolation transformer (102);

an output end of the isolation transformer (102) is connected to a first pole of the second diode (D2), a second pole of the second diode (D2), one end of the fifth capacitor (C5) and one end of the second resistor (R2) are connected to an input end of the light emitting module (003) as output ends of the secondary rectification circuit (20), the other end of the fifth capacitor (C5) and the other end of the second resistor (R2) are both connected to the second ground terminal (PGND), wherein the first pole of the second diode (D2) is an input end of the secondary rectification circuit (20).

10. A light fixture, the light fixture comprising: -a light emitting module (003), and-a power supply circuit (000) as claimed in any one of claims 1 to 9 connected to said light emitting module (003).

11. A luminaire as claimed in claim 10, characterized in that said light module (003) comprises: at least one switching transistor (M0) and a plurality of light emitting modules (L0), each light emitting module (L0) comprising a plurality of light emitting diodes (L01) connected in series;

each switching transistor (M0) is connected with at least one light-emitting component (L0) in series, and the light-emitting component (L0) connected with each switching transistor (M0) is different;

wherein a gate of each of the switching transistors (M0) is connected as a control terminal of the light emitting module (003) to an output terminal of a dimming circuit (30) included in the power supply circuit (000).