Dimming drive circuit and lighting device

Abstract

A dimming drive circuit and a lighting device. The dimming drive circuit is connected to the switching power supply of the light source. The dimming drive circuit adopts a power switching circuit, a control circuit and a dimming circuit. Among them, the control circuit outputs a corresponding first PWM signal according to the preset voltage signal provided by the power switching circuit to control the dimming circuit to adjust the output power of the switching power supply (i.e., the input power of the light source) to the target power, thereby realizing the isolated adjustment of the input power of the light source, avoiding the arcing and sparking faults caused by directly and hard switching the switching resistor, thus affecting the performance and reliability of the circuit, and solving the problem of poor reliability of the traditional light source adjustment circuit.

Description

Technical Field

[0001] This application belongs to the field of dimming technology, and particularly relates to a dimming drive circuit and a lighting device. Background Art

[0002] At present, in traditional light source adjustment circuits, power adjustment is generally performed by directly adjusting the sampling resistance of the converter-set current through a mechanical switch. However, when the circuit current is large, this hard-switching method is prone to arcing, which affects the performance and reliability of the circuit.

[0003] Therefore, traditional light source adjustment circuits have the problem of poor circuit reliability. Summary of the Invention

[0004] The purpose of this application is to provide a dimming drive circuit and a lighting device, aiming to solve the problem of poor circuit reliability in traditional light source adjustment circuits.

[0005] In the first aspect of the embodiments of this application, a dimming drive circuit is provided, which is connected to the switching power supply of a light source. The dimming drive circuit includes:

[0006] A power switch circuit for selectively outputting one of a plurality of preset voltage signals at different voltage values according to an operation, and one preset voltage signal matches one output power of the switching power supply;

[0007] A control circuit, connected to the power switch circuit, for outputting a corresponding first PWM (Pulse Width Modulation) signal according to the preset voltage signal output by the power switch circuit; and

[0008] A dimming circuit, connected to the control circuit, for outputting a corresponding drive signal to the switching power supply under the control of the first PWM signal to adjust the output power.

[0009] In one embodiment, the power switch circuit includes: a first resistor, a first multi-position switch, and at least two second resistors with different resistance values. The first end of the first resistor is connected to a power supply, the second end of the first resistor and the first ends of the respective second resistors are commonly connected to the control circuit, and the second ends of the respective second resistors are grounded through the first multi-position switch. The first multi-position switch is used to connect one or more of the second resistors to output one of the preset voltage signals to the control circuit.

[0010] In one embodiment, the dimming drive circuit further includes a first interface for accessing an adjustment signal and outputting it to the control circuit, and the adjustment signal is used to adjust the matching relationship between the preset voltage signal and the output power.

[0011] In one embodiment, the dimming drive circuit further includes a proportional adjustment circuit. The proportional adjustment circuit is connected to the control circuit and is configured to provide a proportional adjustment signal to the control circuit. The control circuit is configured to adjust the duty cycle of the first PWM signal to a target value according to the proportional adjustment signal.

[0012] In one embodiment, the proportional adjustment circuit includes:

[0013] A fixed adjustment circuit configured to output the proportional adjustment signal within a target voltage range;

[0014] A filter circuit. The filter circuit is connected to the fixed adjustment circuit and the control circuit and is configured to filter out the clutter interference of the proportional adjustment signal; and

[0015] A switch circuit. The switch circuit is connected to the output end of the fixed adjustment circuit and is configured to connect an external voltage signal to increase the voltage value of the proportional adjustment signal or disconnect the input path of the external voltage signal; the voltage value of the proportional adjustment signal matches the ratio.

[0016] In one embodiment, the fixed adjustment circuit includes a dimmer, and the dimmer is configured to output the proportional adjustment signal according to a regulation instruction.

[0017] In one embodiment, the fixed adjustment circuit includes a photosensitive sensor, and the photosensitive sensor is configured to collect the ambient brightness and output the proportional adjustment signal according to the ambient brightness.

[0018] In one embodiment, the dimming drive circuit further includes: an isolation circuit. The isolation circuit is connected in series between the control circuit and the dimming circuit and is configured to isolate and output the first PWM signal to the dimming circuit.

[0019] In one embodiment, the light source includes a plurality of LED lamp strings with different color temperatures, and the dimming drive circuit further includes a color temperature adjustment circuit. The color temperature adjustment circuit is configured to turn on at least one of the LED lamp strings so that the color temperature of the light source is the target color temperature.

[0020] A second aspect of the embodiments of the present application provides an illumination device, including a light source and the dimming drive circuit as described in the first aspect of the embodiments of the present application. The light source is connected to the dimming drive circuit.

[0021] The above dimming drive circuit is connected to the switching power supply of the light source and adopts a power switch circuit, a control circuit, and a dimming circuit. Among them, the control circuit outputs a corresponding first PWM signal according to the preset voltage signal provided by the power switch circuit to control the dimming circuit to adjust the output power of the switching power supply (i.e., the input power of the light source) to the target power, thereby realizing the isolated adjustment of the input power of the light source and avoiding the problem of arcing caused by directly hard-switching the switching resistor, which affects the performance and reliability of the circuit and solves the problem of poor reliability of the traditional light source adjustment circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. is a schematic circuit diagram of a dimming drive circuit provided by an embodiment of the present application;

[0023] Figure 2 For Figure 1 FIG. is a schematic circuit diagram of an example of the power switch circuit of the dimming drive circuit shown;

[0024] Figure 3 For Figure 1 FIG. is another schematic circuit diagram of the dimming drive circuit shown;

[0025] Figure 4 For Figure 1 FIG. is another schematic circuit diagram of the dimming drive circuit shown;

[0026] Figure 5 For Figure 4 FIG. is a schematic circuit diagram of the proportional adjustment circuit of the dimming drive circuit shown;

[0027] Figure 6 For Figure 1 FIG. is another schematic circuit diagram of the dimming drive circuit shown;

[0028] Figure 7 For Figure 6 FIG. is a schematic circuit diagram of an example of the isolation circuit of the dimming drive circuit shown;

[0029] Figure 8 For Figure 1 FIG. is another schematic circuit diagram of the dimming drive circuit shown;

[0030] Figure 9 For Figure 8 FIG. is a schematic circuit diagram of an example of the color temperature adjustment circuit of the dimming drive circuit shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clear and understandable, the following further details this application in combination with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more, unless otherwise specifically defined.

[0035] Figure 1 The structural schematic diagram of the dimming drive circuit 10 provided in the first aspect of the embodiment of this application is shown. For the convenience of description, only the parts related to this embodiment are shown and are described in detail as follows:

[0036] In the dimming drive circuit 10 of this embodiment, it is connected to the switching power supply 20 of the light source 30. The dimming drive circuit 10 includes: a power switch circuit 100, a control circuit 200, and a dimming circuit 300. The output end of the power switch circuit 100 is connected to the first input end of the control circuit 200, and the output end of the control circuit 200 is connected to the dimming circuit 300. The power switch circuit 100 is used to select and output one of a plurality of preset voltage signals at different voltage values according to an operation, and one preset voltage signal matches one output power of the switching power supply 20. The control circuit 200 is used to output a corresponding first PWM signal according to the preset voltage signal. The dimming circuit 300 is used to output a corresponding drive signal to the switching power supply 20 under the control of the first PWM signal to adjust the output power.

[0037] It should be understood that the output terminal of the switching power supply 20 is connected to the light source 30, and the output power of the switching power supply 20 is the input power of the light source 30.

[0038] It should be understood that the power switch circuit 100 is composed of a switch and multiple resistors with different resistance values; the control circuit 200 can be composed of a microprocessor such as a single-chip microcomputer; the dimming circuit 300 can be composed of a dimming constant current driving chip. The light source 30 can be a lamp string composed of one or more LED lights, or an LED array, etc. The switching power supply 20 can be a DC / DC constant voltage conversion circuit.

[0039] It should be understood that a preset voltage signal matches the output power of a switching power supply 20, that is, a preset voltage signal represents a power adjustment parameter, and a power adjustment parameter corresponds to a first PWM signal. For example, a preset voltage signal of 5V matches an output power of 20W. That is, when the preset voltage signal output by the power switch circuit 100 is 5V, the control circuit 200 outputs a corresponding PWM signal to control the dimming circuit 300 to adjust the output power of the switching power supply to 20W. The driving signal is also a pulse width modulation signal.

[0040] In this embodiment, the dimming drive circuit 10 adopts the power switch circuit 100, the control circuit 200 and the dimming circuit 300. The control circuit 200 outputs a corresponding first PWM signal according to the preset voltage signal provided by the power switch circuit 100 to control the dimming circuit 300 to adjust the output power of the switching power supply 20, that is, to adjust the input power of the light source 30 to the target power, thereby realizing the isolated adjustment of the input power of the light source 30, avoiding the problems of arcing and sparking caused by directly hard-switching the switching resistor, which affects the performance and reliability of the circuit, and solving the problem of poor reliability of the traditional light source adjustment circuit.

[0041] In one embodiment, the power switch circuit 100 includes: a first resistor, a first multi-position switch, and at least two second resistors with different resistance values. The first end of the first resistor is connected to the power supply, the second end of the first resistor and the first ends of the respective second resistors are commonly connected to the control circuit 200, and the second ends of the respective second resistors are grounded through the first multi-position switch. The first multi-position switch is used to connect one or more second resistors to output a preset voltage signal to the control circuit 200.

[0042] For example, please refer to Figure 2, the power switch circuit 100 includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, and a first multi-position switch S1. The first end of the resistor R1 is connected to a power supply, and the second end of the resistor R1, the first end of the resistor R2, the first end of the resistor R3, and the first end of the resistor R4 are commonly connected to the control circuit 200. The second end of the resistor R2, the second end of the resistor R3, and the second end of the resistor R4 are grounded through the first multi-position switch S1.

[0043] It should be understood that only the power switch circuit 100 including two preset voltage signals is schematically shown in this embodiment. In other embodiments, the power switch circuit 100 may further include three or more preset voltage signals.

[0044] It should be understood that the first multi-position switch S1 is a mechanical switch such as a DIP switch, a toggle switch, or a push-button switch. The user can directly manually operate to switch the magnitude of the output preset voltage signal, thereby adjusting the input power of the light source 30. The first multi-position switch S1 can also be an electronic switch such as a multiplexer or a multi-way selector switch. The control circuit 200 outputs a level signal to control the on / off state of the first multi-position switch S1. The resistance values of the resistors R2, R3, and R4 are different. The first multi-position switch S1 can connect at least one resistor, so that the power switch circuit 100 outputs different preset voltage signals. Different preset voltage signals represent power parameter adjustments of different gears.

[0045] In the power switch circuit 100 of this embodiment, by using the resistor R1, the resistor R2, the resistor R3, the resistor R4, and the first multi-position switch S1, the output of different preset voltage signals is realized. The circuit is simple and convenient for the user to operate.

[0046] Please refer to Figure 3 , in one embodiment, the dimming drive circuit 10 further includes a first interface 400. The first interface 400 is used to access an adjustment signal and output it to the second input end of the control circuit 200. The adjustment signal is used to adjust the matching relationship between the preset voltage signal and the output power.

[0047] It should be understood that the adjustment signal is used to calibrate the magnitude of the power adjustment parameter represented by the preset voltage signal. For example, before receiving the adjustment signal, a preset voltage signal of 5V is matched with an output power of 20W. After receiving the adjustment signal representing an increase in the power adjustment parameter by 25%, the control circuit 200 matches the 5V preset voltage signal with an output power of 25W.

[0048] Optionally, the first interface 400 is a power calibration interface, and its type can be an electrical connection port, a connector, a USB interface, a wireless communication interface, etc. The adjustment signal is an electrical signal. The first interface 400 can be connected to an external controller or a host computer, and is used to adjust the power adjustment parameters represented by the preset voltage signal according to the adjustment signal output by the external circuit.

[0049] Optionally, the first interface 400 can also be a switch interface. The control circuit 200 reads the number of times the switch is turned on and off, and will modify the matching relationship between the preset voltage signal and the output power.

[0050] In this embodiment, the dimming drive circuit 10 realizes the adjustment of the matching relationship between the preset voltage signal and the output power by adding the first interface 400, and changes the corresponding relationship between the preset voltage signal and the first PWM signal. Therefore, without changing the original circuit hardware design, the input power of the light source 30 can be any target value, solving the problem that the traditional dimming drive circuit 10 cannot be adjusted by the resistor of the original circuit in the face of various special power situations, and it is necessary to find an appropriate resistance value resistor for hardware replacement, which is complicated to operate and may not necessarily find a suitable resistor to change the power.

[0051] Please refer to Figure 4 , in one embodiment, the dimming drive circuit 10 further includes a proportional adjustment circuit 500. The proportional adjustment circuit 500 is connected to the third input end of the control circuit 200. The proportional adjustment circuit 500 is used to provide a proportional adjustment signal to the control circuit 200, and the control circuit 200 is used to adjust the duty cycle of the first PWM signal to a target value in proportion.

[0052] It should be understood that the proportional adjustment signal can be an analog voltage signal within a target voltage range. Each voltage value of the proportional adjustment signal represents a proportional adjustment relationship, that is, a proportional parameter. For example, the third input end of the control circuit 200 detects the proportional adjustment signal (the analog signal voltage range is 0 - 5V, 5V is the maximum, and 0V is the minimum). When the proportional adjustment signal is adjusted within the range of 0 - 5V, the duty cycle of the first PWM signal changes linearly. For example, if the first PWM signal = 50%, and the third input end of the control circuit 200 detects 1V, then the control circuit 200 outputs a PWM signal with a duty cycle of 20% * 50% = 10%; when the third input end of the control circuit 200 detects 5V, it outputs a PWM signal with a duty cycle of 100% * 50% = 50%; if the first PWM signal = 10%, and the third input end of the control circuit 200 detects 1V voltage, then the control circuit 200 outputs a PWM signal with a duty cycle of 20% * 10% = 2%, and when the third input end of the control circuit 200 detects 5V, it outputs a PWM signal with a duty cycle of 100% * 10% = 10%.

[0053] It should be understood that in the dimming drive circuit 10 of this embodiment, by adding a proportional adjustment circuit 500, the control circuit 200 adjusts the duty cycle of the first PWM signal to the target value in proportion and then outputs it to the dimming circuit 300, thereby realizing the secondary adjustment of the light source 30 at a specified power level, that is, realizing the fine adjustment of the input current of the light source 30, so that the brightness of the light source 30 is closer to the target brightness.

[0054] Please refer to Figure 5 , in one embodiment, the proportional adjustment circuit 500 includes: a fixed adjustment circuit 510, a filter circuit 520, and a switch circuit 530. The switch circuit 530 is connected to the output end of the fixed adjustment circuit 510 and the input end of the filter circuit 520. The fixed adjustment circuit 510 is connected to the filter circuit 520 and the switch circuit 530, and the filter circuit 520 is connected to the control circuit 200. The fixed adjustment circuit 510 is used to output a proportional adjustment signal within a target voltage range; the filter circuit 520 is used to filter out the clutter interference of the proportional adjustment signal; the switch circuit 530 is used to connect to an external voltage signal to increase the voltage value of the proportional adjustment signal, or disconnect the input path of the external voltage signal; the voltage value of the proportional adjustment signal matches the adjustment ratio of the duty cycle of the first PWM signal.

[0055] It should be understood that the fixed adjustment circuit 510 can be composed of devices such as a dimmer or a sensor. The filter circuit 520 can be composed of a filter capacitor and a resistor. The switch circuit 530 can be composed of a controllable electronic switch or a mechanical switch. The switch circuit 530 is a preset external interface for connecting to an external voltage signal.

[0056] It should be understood that the voltage value of the proportional adjustment signal matches this ratio. Specifically, it can be positively correlated, that is, the larger the voltage value of the proportional adjustment signal, the larger the adjustment ratio of the duty cycle of the first PWM signal; it can also be negatively correlated, that is, the larger the voltage value of the proportional adjustment signal, the smaller the adjustment ratio of the duty cycle of the first PWM signal. In the proportional adjustment circuit 500 of this embodiment, by adopting the fixed adjustment circuit 510 and the filter circuit 520, the lossless output of the proportional adjustment signal is realized, and by adding the switch circuit 530, the expansion of the voltage range of the proportional adjustment signal is realized. For example, when the proportional adjustment signal output by the fixed adjustment circuit is 10V, at this time, by adding an external voltage signal, for example, 2V, the voltage value of the proportional adjustment signal output to the control circuit 200 is 12V. At this time, the adjustment ratio of the duty cycle of the first PWM signal increases according to the ratio of the voltage value of the external voltage signal to the total target voltage range value.

[0057] In one embodiment, the fixed adjustment circuit 510 includes a dimmer, which is configured to output a proportional adjustment signal according to a regulation instruction. The proportional adjustment signal in this embodiment is an analog voltage signal.

[0058] It should be understood that the dimmer in this embodiment is a dimming controller, and the user can independently select the magnitude of the output proportional adjustment signal, achieving the convenience of adjusting the light source 30.

[0059] In one embodiment, the fixed adjustment circuit 510 includes a photosensitive sensor, which is configured to collect the ambient brightness and output a proportional adjustment signal according to the ambient brightness. The proportional adjustment signal in this embodiment is an analog voltage signal.

[0060] Optionally, when the ambient brightness is relatively high, a low proportional parameter can be output to convert the duty cycle of the first PWM signal into a smaller target value, so as to reduce the input current of the light source 30 to the lowest at the target power level, thereby reducing the brightness of the light source 30 and saving energy consumption.

[0061] The fixed adjustment circuit 510 in this embodiment, by adopting a photosensitive sensor, realizes automatically outputting a proportional adjustment signal according to the ambient brightness to further adjust the first PWM signal, enabling the light source 30 to autonomously adapt to the ambient brightness requirement at the target power level, saving unnecessary energy consumption and realizing the intelligent control of the light source 30.

[0062] Optionally, in other embodiments, the fixed adjustment circuit 510 may further include a sound sensor, which collects sound and outputs a proportional adjustment signal according to the intensity of the sound, thereby realizing further voice control adjustment of the first PWM signal at the target power level.

[0063] Please refer to Figure 6 , in one embodiment, the dimming drive circuit 10 further includes an isolation circuit 600, which is connected in series between the control circuit 200 and the dimming circuit 300. The isolation circuit 600 is configured to isolate and output the first PWM signal to the dimming circuit 300.

[0064] It should be understood that the isolation circuit 600 may be composed of isolation devices such as an optocoupler U1. The dimming drive circuit 10 in this embodiment, by adding the isolation circuit 600, realizes the isolated output of the first PWM signal, making the dimming drive circuit 10 more secure and reliable.

[0065] Please refer to Figure 7, in one embodiment, the isolation circuit 600 includes an optocoupler U1, a first capacitor C1, a first zener diode D1, a first switching transistor Q1, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10. The fifth resistor R5 is connected to the control circuit 200. The second terminal of the fifth resistor R5 is connected to the positive input terminal of the optocoupler U1. The negative input terminal of the optocoupler U1 and the first terminal of the first capacitor C1 are commonly connected to ground. The second terminal of the first capacitor C1 and the negative output terminal of the optocoupler U1 are commonly connected to ground. The positive electrode of the first zener diode D1 is grounded, and the negative electrode of the first zener diode D1 is connected to the positive output terminal of the optocoupler U1. The positive output terminal of the optocoupler U1 is further connected to the control terminal of the first switching transistor Q1 and the second terminal of the seventh resistor R7. The first terminal of the seventh resistor R7, the second terminal of the sixth resistor R6, and the first terminal of the eighth resistor R8 are commonly connected. The first terminal of the sixth resistor R6 is connected to the power supply. The second terminal of the eighth resistor R8, the first terminal of the ninth resistor R9, and the high-potential terminal of the first switching transistor Q1 are commonly connected. The second terminal of the ninth resistor R9 and the first terminal of the tenth resistor R10 are commonly connected to the dimming circuit 300. The second terminal of the tenth resistor R10 is grounded, and the low-potential terminal of the first switching transistor Q1 is grounded. Optionally, the first switching transistor Q1 is a controllable switching transistor such as a MOS transistor or a triode.

[0066] Please refer to Figure 8 , in one embodiment, the light source 30 includes a plurality of LED lamp strings with different color temperatures. The dimming drive circuit 10 further includes a color temperature adjustment circuit 700, and the color temperature adjustment circuit 700 is used to turn on at least one LED lamp string so that the color temperature of the light source 30 is the target color temperature.

[0067] It should be understood that the color temperature adjustment circuit 700 in this embodiment can be directly switched by a multi-stage mechanical switch to adjust the color temperature, or a multi-way electronic switch can be used to switch to adjust the color temperature.

[0068] Optionally, please refer to Figure 9, in one embodiment, the light source 30 includes two LED lamp strings with different color temperatures. The color temperature adjustment circuit 700 includes a second switching transistor Q2, a third switching transistor Q3, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, and a second multi-position switch S2. The positive electrode of the first LED lamp string 31 is connected to the high-potential end of the second switching transistor Q2, the first end of the eleventh resistor R11, the high-potential end of the third switching transistor Q3, and the first end of the twelfth resistor R12. The second end of the eleventh resistor R11 is connected to the control end of the second switching transistor Q2 and the first terminal on the second side of the second multi-position switch S2. The second end of the twelfth resistor R12 is connected to the control end of the third switching transistor Q3 and the second terminal on the second side of the second multi-position switch S2. The first terminal and the second terminal on the first side of the second multi-position switch S2 are commonly connected to the second end of the thirteenth resistor R13. The first end of the thirteenth resistor R13 is connected to the positive electrode of the second LED lamp string 32. The low-potential end of the second switching transistor Q2 is connected to the negative electrode of the first LED lamp string 31. The low-potential end of the third switching transistor Q3 is connected to the negative electrode of the second LED lamp string 32.

[0069] It should be understood that in this embodiment, three different color temperature adjustments can be achieved by only closing the first LED lamp string 31, only closing the second LED lamp string 32, or closing the first LED lamp string 31 and the second LED lamp string 32 simultaneously. In this embodiment, only the case where the light source 30 includes two LED lamp strings with different color temperatures is schematically shown. In other embodiments, the light source 30 further includes three or more LED lamp strings with different color temperatures. Correspondingly, the second multi-position switch S2 is a three-position or more switch, and the number of switching transistors is three or more.

[0070] Optionally, the switching power supply 20 can be connected to the mains through an AC / DC constant voltage circuit 40. The switching power supply 20 can be a switching power supply circuit including a switching transistor, an inductor, etc. The AC / DC constant voltage circuit 40 can be composed of a rectifying bridge and a constant voltage control chip.

[0071] A second aspect of the embodiments of the present application provides an illumination device, including a light source and a dimming drive circuit as described in the first aspect of the embodiments of the present application. The light source is connected to the dimming drive circuit.

[0072] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above division of each functional unit and module is used as an example. In actual applications, the above functions can be assigned to different functional units and modules according to needs, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiments can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction and do not limit the protection scope of this application. The specific working processes of the units and modules in the above system can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated here.

[0073] In the above embodiments, the descriptions of the various embodiments have their own emphases. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or by a combination of computer software and electronic hardware. Whether these functions are executed in the form of hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0075] In the embodiments provided in this application, it should be understood that the disclosed device / terminal device and method can be implemented in other ways. For example, the device / terminal device embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical functional division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some interfaces. The indirect coupling or communication connection of the device or unit can be in an electrical, mechanical or other form.

[0076] The unit described as a separated component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0077] In addition, in each embodiment of the present application, each functional unit may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0078] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on such an understanding, all or part of the processes in the above-mentioned embodiment methods of the present application can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-mentioned various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0079] The above-mentioned embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A dimming drive circuit is connected to the switching power supply of a light source, and is characterized in that The dimming drive circuit includes: A power switch circuit for selectively outputting one of a plurality of preset voltage signals at different voltage values according to an operation, and one preset voltage signal matches the output power of the switching power supply; A control circuit connected to the power switch circuit for outputting a corresponding first PWM signal according to the preset voltage signal output by the power switch circuit; and A dimming circuit connected to the control circuit for outputting a corresponding drive signal to the switching power supply under the control of the first PWM signal to adjust the output power; A first interface for accessing an adjustment signal and outputting it to the control circuit, the adjustment signal being used to adjust the matching relationship between the preset voltage signal and the output power, and the adjustment signal being used to calibrate the magnitude of the power adjustment parameter represented by the preset voltage signal; A proportional adjustment circuit connected to the control circuit for providing a proportional adjustment signal to the control circuit, and the control circuit is used to adjust the duty cycle of the first PWM signal to a target value according to the proportional adjustment signal.

2. The dimming drive circuit according to claim 1, wherein The power switch circuit includes: a first resistor, a first multi-position switch, and at least two second resistors with different resistance values. The first end of the first resistor is connected to a power supply, and the second end of the first resistor and the first ends of the respective second resistors are commonly connected to the control circuit. The second ends of the respective second resistors are grounded through the first multi-position switch, and the first multi-position switch is used to connect one or more of the second resistors to output a preset voltage signal to the control circuit.

3. The dimming drive circuit according to claim 1, wherein, The proportional adjustment circuit includes: A fixed adjustment circuit for outputting the proportional adjustment signal within a target voltage range; A filter circuit, the filter circuit being connected to the fixed adjustment circuit and the control circuit, and the filter circuit is used to filter out the clutter interference of the proportional adjustment signal; and A switch circuit, the switch circuit being connected to the output end of the fixed adjustment circuit, and the switch circuit is used to access an external voltage signal to increase the voltage value of the proportional adjustment signal, or disconnect the input path of the external voltage signal; the voltage value of the proportional adjustment signal matches the ratio.

4. The dimming drive circuit according to claim 3, wherein, The fixed adjustment circuit includes a dimmer for outputting the proportional adjustment signal according to a control command.

5. The dimming drive circuit according to claim 3, wherein, The fixed adjustment circuit includes a photosensitive sensor for collecting the ambient brightness and outputting the proportional adjustment signal according to the ambient brightness.

6. The dimming drive circuit according to claim 1, characterized in that, It further includes: An isolation circuit, the isolation circuit being connected in series between the control circuit and the dimming circuit, and the isolation circuit is used to isolate and output the first PWM signal to the dimming circuit.

7. The dimming drive circuit according to any one of claims 1-6, characterized in that The light source includes a plurality of LED lamp strings with different color temperatures, and the dimming drive circuit further includes a color temperature adjustment circuit for turning on at least one of the LED lamp strings so that the color temperature of the light source is the target color temperature.

8. A lighting device, characterized in that, It includes: A light source; and The dimming drive circuit according to any one of claims 1 to 7, the light source being connected to the dimming drive circuit.

Images