Stepless dimming device and stepless dimming control method

Abstract

The present invention discloses a stepless dimming device and a stepless dimming control method. Relating to the field of lighting, the control circuit in the stepless dimming device of the embodiment of the present application is used to generate a start-stop signal to control the start and stop of a light source and to generate a brightness adjustment signal to adjust the brightness of the light source. The first light source driving circuit is connected to the light source and the control circuit, and is used to adjust the brightness of the light source according to the first brightness adjustment signal or the second brightness adjustment signal; the second light source driving circuit is connected to the light source and the control circuit, and is used to adjust the brightness of the light source according to the second brightness adjustment signal. In this embodiment, by setting two light source driving circuits, the brightness of the light source can be adjusted within a large current adjustment range, thereby achieving stepless dimming of a wide range of brightness, improving the user experience of the stepless dimming device, and expanding the usage scenarios.

Description

Technical Field

[0001] The present invention belongs to the field of lighting, and more specifically, relates to a stepless dimming device and a stepless dimming control method. Background Art

[0002] Lighting equipment is widely used in our daily life, such as flashlights, table lamps, ceiling lamps, etc. At present, most lighting equipment uses light-emitting diodes as light sources, which have the advantages of energy saving, durability, and high brightness. However, many lighting equipments adjust the brightness by step dimming, which cannot achieve continuous and smooth brightness adjustment. Summary of the invention

[0003] The main purpose of the embodiments of the present application is to provide a stepless dimming device that can achieve continuous and smooth adjustment of light brightness, thereby effectively improving the use scenarios of related equipment.

[0004] According to a first aspect of an embodiment of the present invention, a stepless dimming device is provided, comprising:

[0005] light source;

[0006] A control circuit, for generating a brightness adjustment signal according to a brightness range operation instruction, wherein when the brightness range operation instruction is a first brightness range operation instruction, the brightness adjustment signal is a first brightness adjustment signal, when the brightness range operation instruction is a second brightness range operation instruction, the brightness adjustment signal is a second brightness adjustment signal, and when the brightness range operation instruction is a third brightness range operation instruction, the brightness adjustment signal is a third brightness adjustment signal; the first brightness adjustment signal includes: a first current range signal and a constant voltage mode signal, the second brightness adjustment signal includes: a second current range signal and a constant current mode signal, and the third brightness adjustment signal includes: a third current range signal and a constant current mode signal; the first brightness range is smaller than the second brightness range, the second brightness range is smaller than the third brightness range, the first current range is smaller than the second current range, and the second current range is smaller than the third current range;

[0007] a first light source driving circuit connected to the light source and the control circuit, and configured to adjust the brightness of the light source according to the first brightness adjustment signal or the second brightness adjustment signal;

[0008] The second light source driving circuit is connected to the light source and the control circuit, and is used to adjust the brightness of the light source according to the third brightness adjustment signal.

[0009] In a specific embodiment of the present invention, the first light source driving circuit comprises:

[0010] a first current detection circuit, connected to the first synchronous rectification circuit and the light source, and used for detecting the real-time current of the light source;

[0011] a first feedback circuit, connected to the control circuit and the first current detection circuit, and configured to change an output voltage value of the light source according to the first brightness adjustment signal;

[0012] The first synchronous rectification circuit is connected to the control circuit, and is used to send the output voltage value to the control circuit, or to change the output voltage value of the light source according to the real-time current.

[0013] In a specific embodiment of the present invention, the first feedback circuit includes a first voltage-dividing resistor, and when the brightness adjustment signal is a first brightness adjustment signal:

[0014] The control circuit is used to generate a conduction control signal to change the first divided voltage value of the first divided voltage resistor;

[0015] The first feedback circuit is used to change the output voltage value output to the light source according to the first divided voltage value;

[0016] The first synchronous rectification circuit is used to feed back the output voltage value to the control circuit, so that the control circuit changes the conduction control signal according to the output voltage value of the light source.

[0017] In a specific embodiment of the present invention, the first feedback circuit includes a second voltage-dividing resistor, and when the brightness adjustment signal is a second brightness adjustment signal:

[0018] The first current detection circuit is used to detect the real-time current of the light source and convert the real-time current into a real-time voltage;

[0019] The control circuit is used to change the second resistance value of the second voltage-dividing resistor;

[0020] The first synchronous rectification circuit is used for obtaining a second divided voltage value according to the real-time voltage and the second resistance value, and changing an output voltage value output to the light source according to the second divided voltage value.

[0021] In a specific embodiment of the present invention, the second light source driving circuit comprises:

[0022] a second current detection circuit, connected to the second synchronous rectification circuit and the light source, and used for detecting the real-time current of the light source;

[0023] a second feedback circuit, connected to the control circuit and the second current detection circuit, and configured to obtain a real-time current of the light source according to the third brightness adjustment signal;

[0024] The second synchronous rectification circuit is connected to the control circuit and is used for changing the output voltage value of the light source according to the real-time current.

[0025] In a specific embodiment of the present invention, the second feedback circuit includes a third voltage-dividing resistor, and when the brightness adjustment signal is a third brightness adjustment signal:

[0026] The second current detection circuit is used to detect the real-time current on the light source and convert the real-time current into a real-time voltage;

[0027] The control circuit is used to change the third resistance value of the third voltage-dividing resistor;

[0028] The second synchronous rectification circuit is used for obtaining a third divided voltage value according to the real-time voltage and the third resistance value, and changing an output voltage value output to the light source according to the third divided voltage value.

[0029] In a specific embodiment of the present invention, the stepless dimming device further comprises:

[0030] A charge and discharge protection circuit has one end connected to the control circuit and the other end connected to the power supply device, and is used to charge or discharge the power supply device according to the charge and discharge signal sent by the control circuit.

[0031] In a specific embodiment of the present invention, the stepless dimming device further comprises:

[0032] The anti-reverse connection circuit has one end connected to the power supply and the other end connected to the charge and discharge protection circuit, and is used to disconnect the power supply when the power supply is reversely connected.

[0033] A second aspect of the present invention provides a stepless dimming control method, which is applied to the stepless dimming device as described in any one of the first aspects, and the method comprises:

[0034] Generate a brightness adjustment signal according to the brightness range operation instruction;

[0035] Sending the first brightness adjustment signal or the second brightness adjustment signal to the first light source driving circuit to adjust the brightness of the light source;

[0036] The third brightness adjustment signal is sent to the second light source driving circuit to adjust the brightness of the light source.

[0037] One of the above technical solutions of the present application has at least one of the following advantages or beneficial effects: the control circuit of the stepless dimming device is used to generate a start-stop signal to control the start and stop of the light source and to generate a brightness adjustment signal to adjust the brightness of the light source, and the brightness adjustment signal includes: a first brightness adjustment signal, a second brightness adjustment signal and a third brightness adjustment signal, and the first light source driving circuit is connected to the light source and the control circuit, and is used to adjust the brightness of the light source according to the first brightness adjustment signal or the second brightness adjustment signal; the second light source driving circuit is connected to the light source and the control circuit, and is used to adjust the brightness of the light source according to the second brightness adjustment signal. In this embodiment, by setting two light source driving circuits, the brightness of the light source can be adjusted within a large current adjustment range, thereby realizing stepless dimming of a wide range of brightness, improving the user experience of the stepless dimming device, and expanding the usage scenarios.

[0038] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a schematic diagram of a stepless dimming device according to an embodiment of the present invention;

[0040] Figure 2 is a circuit diagram of a stepless dimming device according to another embodiment of the present invention;

[0041] Figure 3 is a schematic diagram of a control circuit of a stepless dimming device according to another embodiment of the present invention;

[0042] Figure 4 is a schematic diagram of a stepless dimming device according to another embodiment of the present invention;

[0043] Figure 5 It is a flow chart of a stepless dimming control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0045] In addition, the terms "first", "second", "third", "fourth", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", "third", "fourth", etc. may explicitly or implicitly include one or more features.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be internal connection between two elements, indirect connection, or an interactive relationship between two elements.

[0047] The following disclosure provides many different embodiments or examples for implementing different solutions of the present invention.

[0048] Lighting equipment is widely used in daily life, such as flashlights, table lamps, ceiling lamps, etc. At present, most lighting equipment uses light-emitting diodes as light sources, which have the advantages of power saving, durability, and high brightness. However, many lighting equipments adjust the brightness by dimming in different steps, which cannot achieve continuous and smooth adjustment of the brightness. In some embodiments, the control circuit described below can be implemented by a main control chip. For example, the main control chip can be an MCU control chip.

[0049] Reference Figure 1 The stepless dimming device of the embodiment of the present invention includes: a light source 100, a control circuit 200, a first light source driving circuit 300 and a second light source driving circuit 400.

[0050] The light source 100 may be an LED lamp bead, such as a single-color LED lamp bead, a two-color LED lamp bead or a three-color LED lamp bead, and the light source 100 is not limited here.

[0051] The control circuit 200 is used to generate a start / stop signal to control the start / stop of the light source 100 , wherein the start / stop signal may include: a start signal and a stop signal, wherein the start signal is used to control the light source 100 to be turned on, and the stop signal is used to control the light source 100 to be turned off.

[0052] In this embodiment, the control circuit 200 is also used to generate a brightness adjustment signal according to the brightness range operation instruction. When the brightness range operation instruction is a first brightness range operation instruction, the brightness adjustment signal is a first brightness adjustment signal. When the brightness range operation instruction is a second brightness range operation instruction, the brightness adjustment signal is a second brightness adjustment signal. When the brightness range operation instruction is a third brightness range operation instruction, the brightness adjustment signal is a third brightness adjustment signal. The first brightness adjustment signal includes: a first current range signal and a constant voltage mode signal. The second brightness adjustment signal includes: a second current range signal and a constant current mode signal. The third brightness adjustment signal includes: a third current range signal and a constant current mode signal. The first brightness range is smaller than the second brightness range, the second brightness range is smaller than the third brightness range, the first current range is smaller than the second current range, and the second current range is smaller than the third current range.

[0053] The first light source driving circuit 300 is connected to the light source 100 and the control circuit 200, and is used to adjust the brightness of the light source 100 according to the first brightness adjustment signal or the second brightness adjustment signal. The second light source driving circuit 400 is connected to the light source 100 and the control circuit 200, and is used to adjust the brightness of the light source 100 according to the second brightness adjustment signal.

[0054] In this embodiment, the first brightness adjustment signal includes: a first current range signal and a constant voltage mode signal, wherein the first current range signal is used to characterize the current range of the real-time current is 0mA-500mA, or 50mA-500mA. The second brightness adjustment signal includes: a second current range signal and a constant current mode signal, wherein the second current range signal is used to characterize the real-time current, and the current range of the real-time current is 500mA-1400mA. The third brightness adjustment signal includes: a third current range signal and a constant current mode signal, wherein the third current range signal is used to characterize the real-time current, and the current range of the real-time current is 1400mA-5000mA. It can be understood that the current range in this embodiment is only for illustration, and different current ranges can be divided according to actual needs.

[0055] It can be seen that in this embodiment, the stepless dimming device uses the control circuit 200 to generate a brightness adjustment signal to adjust the brightness of the light source. The first light source driving circuit 300 is connected to the light source and the control circuit 200, and adjusts the brightness of the light source according to the first brightness adjustment signal or the second brightness adjustment signal; the second light source driving circuit 400 is connected to the light source and the control circuit 200, and adjusts the brightness of the light source according to the second brightness adjustment signal. In this embodiment, by setting two light source driving circuits, the current of the light source is adjusted in a large current adjustment range (such as the above-mentioned current range of 0mA-5000mA), thereby realizing stepless dimming of a wide range of brightness, improving the user experience of the stepless dimming device, and expanding the usage scenarios.

[0056] Reference Figure 2 , is a circuit diagram of a stepless dimming device according to an embodiment of the present application.

[0057] In one embodiment of the present application, the first light source driving circuit 300 includes:

[0058] The first synchronous rectification circuit 310 is connected to the control circuit 200 and is also used for an external power supply, and outputs after reducing the voltage of the external power supply; the first current detection circuit 320 is connected to the first synchronous rectification circuit 310 and the light source 100, and is used to detect the real-time current of the light source 100; the first feedback circuit 330 is connected to the control circuit 200 and the first current detection circuit 320, and is used to change the output voltage value of the light source 100 according to the first brightness adjustment signal. The first synchronous rectification circuit 310 is also connected to the control circuit 200, and is used to send the output voltage value to the control circuit 200, and is also used to change the output voltage value of the light source 100 according to the real-time current.

[0059] Figure 2 In the figure, the light source 100 is a light emitting LED diode, namely LED1, and the circuit structure of the first synchronous rectification circuit 310 includes: a first capacitor group, a fourth chip IC4, a first inductor L1 and a second capacitor group connected in sequence.

[0060] Among them, the first capacitor group is a filter capacitor, and each capacitor thereof is connected in parallel, one end of which is grounded after parallel connection, and the other end is connected to the first input pin Vin of the fourth chip IC4, and each capacitor in the first capacitor group is: a first capacitor C1, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a seventh capacitor C7, and a ninth capacitor C9. It can be understood that the number and combination of each capacitor in the first capacitor group in this embodiment are only for illustration, and do not represent that it is limited to this method.

[0061] The capacitors in the second capacitor group are connected in parallel, and the capacitors in the second capacitor group are: the eleventh capacitor C11, the twelfth capacitor C12, the thirteenth capacitor C13, the fourteenth capacitor C14, the fifteenth capacitor C15, the sixteenth capacitor C16, the seventeenth capacitor C17, the eighteenth capacitor C18 and the nineteenth capacitor C19, and one end is grounded after being connected in parallel. It can be understood that the number and combination of the capacitors in the second capacitor group in this embodiment are only for illustration, and do not represent that it is limited to this method.

[0062] The fourth chip IC4 is a power management chip, for example, the model may be MP2147. The fourth chip IC4 includes: a first feedback pin FB4 (pin 3 of the fourth chip IC4 in the figure), a first enable pin EN4 (pin 5 of the fourth chip IC4 in the figure), a second feedback pin OUT4 (pin 2 of the fourth chip IC4 in the figure), a first input pin Vin4 (pin 6 of the fourth chip IC4 in the figure) and a first output pin SW4 (pin 1 and pin 2 of the fourth chip IC4 in the figure are output in series). For other pins of the fourth chip IC4, please refer to the chip user manual, which will not be listed here one by one.

[0063] In this embodiment, the output of the first capacitor group is connected to the first input pin Vin4 of the fourth chip IC4, for inputting the filtered voltage to the fourth chip IC4, the first output pin SW4 of the fourth chip IC4 is connected to the input end of the first inductor L1, and the second feedback pin OUT4 of the fourth chip IC4 is connected between the first inductor L1 and the second capacitor group.

[0064] Figure 2 In the embodiment, the circuit structure of the first current detection circuit 320 includes: a third resistor R3, a sixth capacitor C6 and a third chip IC3, wherein the third resistor R3 and the sixth capacitor C6 are connected in parallel.

[0065] In this embodiment, the third chip IC3 is a high-precision current sampling chip, for example, the model may be INA199. The third chip IC3 includes: a third input pin V+ (pin 3 of the third chip IC3 in the figure), a third high-end input pin IN+ (pin 4 of the third chip IC3 in the figure), a third low-end input pin IN- (pin 5 of the third chip IC3 in the figure), and a third output pin OUT3 (pin 6 of the third chip IC3 in the figure).

[0066] Among them, the third high-end input pin IN+ and the third low-end input pin IN- of the third chip IC3 are two inputs of the operational amplifier, the third high-end input pin IN+ is connected to one end of the third resistor R3 and the sixth capacitor C6, and the third low-end input pin IN- is connected to the other end of the third resistor R3 and the sixth capacitor C6. The third input pin V+ of the third chip IC3 is connected to the first enable pin EN4 of the fourth chip IC4, and the pin 1 of the third chip IC3 is connected to the pin 1 of the fourth chip IC4.

[0067] Figure 2 In the embodiment, the circuit structure of the first feedback circuit 330 includes: a first resistor R1 and a second voltage dividing resistor.

[0068] In this embodiment, the second voltage-dividing resistor is obtained by connecting a plurality of resistors in parallel, for example, the second voltage-dividing resistor includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13 and a fifteenth resistor R15. It can be understood that the number and combination of the resistors in the first voltage-dividing resistor in this embodiment are only for illustration and do not limit this method.

[0069] Among them, one end of the first resistor R1 is connected to the third output pin OUT3 of the third chip IC3 of the first current detection circuit 320, and the other end is connected in series with the second voltage dividing resistor, and the first feedback pin FB4 of the fourth chip IC4 of the first synchronous rectification circuit 310 is connected between the first resistor R1 and the second voltage dividing resistor.

[0070] In one embodiment of the present application, the second light source driving circuit 400 includes:

[0071] The second synchronous rectification circuit 410 is connected to the control circuit 200, and is also used for an external power supply, and outputs the external power supply after stepping down the voltage; the second current detection circuit 420 is connected to the second synchronous rectification circuit 410 and the light source 100, and is used for detecting the real-time current of the light source 100; the second feedback circuit 430 is connected to the control circuit 200 and the second current detection circuit 420, and is used for changing the output voltage value of the light source according to the real-time current.

[0072] Reference Figure 2 The circuit structure of the second synchronous rectification circuit 410 includes: a first capacitor group, a sixth chip IC6, a second inductor L2 and a second capacitor group connected in sequence. Since the first capacitor group and the second capacitor group are also in the first synchronous rectification circuit 310, the first capacitor group and the second capacitor group are not shown in the second synchronous rectification circuit 410.

[0073] Among them, one end of the first capacitor group is connected to the first input pin Vin of the sixth chip IC6. The sixth chip IC6 is a power management chip, for example, the signal can be MP2147. The sixth chip IC6 includes: a second feedback pin FB6 (pin 3 of the sixth chip IC6 in the figure), a second enable pin EN6 (pin 5 of the sixth chip IC6 in the figure), a fourth feedback pin OUT6 (pin 2 of the sixth chip IC6 in the figure), a second input pin Vin6 (pin 6 of the sixth chip IC6 in the figure) and a second output pin SW6 (pin 1 and pin 2 of the sixth chip IC6 in the figure are output in series). The other pins of the sixth chip IC6 can be referred to the chip manual, which are not listed here one by one.

[0074] In this embodiment, the output of the first capacitor group is connected to the second input pin Vin6 of the sixth chip IC6, for inputting the filtered voltage to the sixth chip IC6, the second output pin SW6 of the sixth chip IC6 is connected to the input end of the second inductor L2, and the second feedback pin OUT4 of the sixth chip IC6 is connected between the second inductor L2 and the second capacitor group.

[0075] Figure 2 In the embodiment, the circuit structure of the second current detection circuit 420 includes: a fourth resistor R4, a fifth resistor R5, an eighth capacitor C8 and a fifth chip IC5.

[0076] In this embodiment, the fifth chip IC5 is a high-precision current sampling chip, for example, the model may be INA199. The fifth chip IC5 includes: a fifth input pin V+ (pin 3 of the fifth chip IC5 in the figure), a fifth high-end input pin IN+ (pin 4 of the fifth chip IC5 in the figure), a fifth low-end input pin IN- (pin 5 of the fifth chip IC5 in the figure), and a fifth output pin OUT3 (pin 6 of the fifth chip IC5 in the figure).

[0077] Among them, the fifth high-end input pin IN+ and the third low-end input pin IN- of the fifth chip IC5 are two inputs of the operational amplifier, the fifth high-end input pin IN+ is connected to one end of the fourth resistor R4, the fifth resistor R5 and the eighth capacitor C8, the fifth low-end input pin IN- is connected to the other end of the fourth resistor R4, the fifth resistor R5 and the eighth capacitor C8, and the fourth resistor R4 and the fifth resistor R5 are respectively connected in parallel with the eighth capacitor. The fifth input pin V+ of the fifth chip IC5 is connected to the second enable pin EN6 of the sixth chip IC6, and the pin 1 of the fifth chip IC5 is connected to the pin 1 of the sixth chip IC6.

[0078] Reference Figure 2 , the circuit structure of the second feedback circuit 430 includes: a second resistor R2 and a third voltage-dividing resistor.

[0079] In this embodiment, the third voltage-dividing resistor is obtained by connecting a plurality of resistors in parallel, for example, the third voltage-dividing resistor includes: a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22 and a twenty-seventh resistor R27. It can be understood that the number and combination of the resistors in the third voltage-dividing resistor in this embodiment are only for illustration and do not limit this method.

[0080] Among them, one end of the second resistor R2 is connected to the fifth output pin OUT5 of the fifth chip IC5 of the second current detection circuit 420, and the other end is connected in series with the third voltage dividing resistor, and the first feedback pin FB6 of the sixth chip IC6 of the second synchronous rectification circuit 410 is connected between the second resistor R2 and the third voltage dividing resistor.

[0081] At the same time, refer to Figure 2 The third output pin OUT3 of the third chip IC3 of the first light source driving circuit 300 is connected to one end of the light source 100 (ie, LED1), and the fifth output pin OUT5 of the fifth chip IC5 of the second light source driving circuit 400 is connected to one end of the light source 100 (ie, LED1).

[0082] Reference Figure 3 , is a schematic diagram of a control circuit in an embodiment of the present application.

[0083] In this embodiment, the control circuit 200 is responsible for controlling the start and stop of the light source 100 and the brightness adjustment of the light source 100. The control circuit 200 includes: an MCU chip 210 and a peripheral circuit, wherein the model of the MCU chip 210 may be AD156. Among them, pins 32, 31, 30, 29, 25, 24 and 24 in the MCU chip 210 are respectively connected to the sixth resistor R6 and the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the tenth resistor R10, the eleventh resistor R11 and the twelfth resistor R12 in the second voltage-dividing resistor of the first feedback circuit 330, the thirteenth resistor R13 in the second voltage-dividing resistor is connected to pin 21, and the fifteenth resistor R15 in the second voltage-dividing resistor is connected to pin 19. Pin 20 is connected to the gate of the P-type field effect transistor Q3, pin 18 is connected to the third input pin V+ of the third chip IC3 and the first enable pin EN4 of the fourth chip IC4, and pin 16 is connected to the second enable pin EN6 of the sixth chip IC6 of the second light source driving circuit 400. Pin 6, pin 7, pin 1, pin 10, pin 11, pin 12, pin 13 and pin 5 in the MCU chip 210 are respectively connected to the sixteenth resistor R16, the seventeenth resistor R17, the eighteenth resistor R18, the nineteenth resistor R19, the twentieth resistor R20, the twenty-first resistor R21, the twenty-second resistor R22 and the twenty-seventh resistor R27 in the two-voltage divider resistor of the second feedback module 430. Pin 15, pin 16 and pin 14 are respectively connected to the second switch TP2, the third switch TP3 and the fourth switch TP4, respectively corresponding to: switch button, current increase button (corresponding to stepless dimming brightness enhancement) and current reduction button (corresponding to stepless dimming brightness reduction). Other peripheral circuit connections are not described one by one here.

[0084] In this embodiment, the brightness range operation instruction, i.e., the current increase button or the current decrease button is pressed, the first brightness range operation instruction means that the current range corresponding to the current adjustment of the brightness of the light source is within the first current range, and the corresponding brightness adjustment signal is the first brightness adjustment signal; the second brightness range operation instruction means that the current range corresponding to the current adjustment of the brightness of the light source is within the second current range, and the corresponding brightness adjustment signal is the second brightness adjustment signal; the third brightness range operation instruction means that the current range corresponding to the current adjustment of the brightness of the light source is within the third current range, and the corresponding brightness adjustment signal is the third brightness adjustment signal. When the current increase button is pressed, the MCU chip 210 determines which current range the light source belongs to based on the current current of the light source, and determines the corresponding brightness adjustment signal based on the current range, thereby performing stepless dimming on the light source to achieve brightness enhancement. When the current increase and decrease button is pressed, the MCU chip 210 determines which current range the light source belongs to based on the current current of the light source, and determines the corresponding brightness adjustment signal based on the current range, thereby performing stepless dimming on the light source to achieve brightness reduction.

[0085] In one embodiment, the I / O port (pin 17) of the MCU chip 210 sends a high-level signal to enable the fourth chip IC4 of the first light source driving circuit 300 of the subsequent stage, or the pin 16 sends a high-level signal to enable the sixth chip IC6 of the second light source driving circuit 400, and the first light source driving circuit 300 or the second light source driving circuit 400 is selected according to the current regulation signal. Since the fourth chip IC4 is connected to the third chip IC3, the third output pin OUT3 of the third chip IC3 is connected to the light source 100 (i.e., LED1), the sixth chip IC6 is connected to the fifth chip IC5, and the third output pin OUT5 of the fifth chip IC5 is connected to the light source 100 (i.e., LED1). Therefore, the high-level signal or low-level signal of the MCU chip 210 can control the start and stop of the LED1 of the light source 100, and the start and stop signal may include: a start signal and a stop signal, wherein the start signal is used to control the opening of the light source 100, and the stop signal is used to control the closing of the light source 100. After the fourth chip IC4 or the sixth chip IC6 is started, normal operation can be achieved through the matching peripheral discrete components.

[0086] In one embodiment, the control circuit 200 generates adjustment signals for different current ranges according to the required current size, namely: a first brightness adjustment signal (the current range is 0mA-500mA, or 50mA-500mA), a second brightness adjustment signal (the current range is 500mA-1400mA) and a third brightness adjustment signal (the current range is 1400mA-5000mA).

[0087] Since the output current range of the load is limited by the feedback voltage range of the chip, it cannot be directly adjusted in a large current range of 0mA-5000mA. Therefore, this embodiment adopts two groups of light source driving circuits to operate in different current ranges, namely: the first light source driving circuit 300 operates at 0mA-1400mA, and the second light source driving circuit 400 operates at 1400mA-5000mA. At the same time, in order to ensure the adjustment accuracy of the stepless dimming, at 0mA-500mA, a constant voltage mode is adopted, at 500mA-1400mA, a constant current mode is adopted, and at 1400mA-5000mA, a constant current mode is adopted.

[0088] In one embodiment, when the first light source driving circuit 300 is working, the first enable pin EN4 of the fourth chip IC4 is powered on and enabled, and at the same time, since the third input pin V+ of the third chip IC3 is connected to the first enable pin EN4 of the fourth chip IC4, the third chip IC3 is also powered on, and at this time, the first synchronous rectification step-down circuit 310 is externally connected to the power supply, and the first capacitor group (i.e., the filter capacitor) first filters the input voltage of the power supply, and then the filtered voltage drives the fourth chip IC4, so that the first output pin SW4 of the fourth chip IC4 and the second feedback pin OUT4 of the fourth chip IC4 output voltage to the first inductor L1 and the second capacitor group. The second light source driving circuit 400 works similarly and is not described one by one here.

[0089] In one embodiment, when the brightness adjustment signal is the first brightness adjustment signal, that is, the current range of the real-time current is 0mA-500mA, and the working mode is the constant voltage mode, the working principle of the multi-level dimming is described as follows:

[0090] The control circuit 200 generates a conduction control signal to change the first voltage-dividing value of the first voltage-dividing resistor, and the first feedback circuit 330 changes the output voltage value output to the light source 100 according to the first voltage-dividing value; the first synchronous rectification circuit 310 detects the output voltage value of the light source 100 in real time and feeds back to the control circuit 200, so that the control circuit 200 changes the conduction control signal according to the output voltage value of the light source.

[0091] In one embodiment, referring to Figure 2 The first feedback circuit 330 also includes: a first voltage-dividing resistor and a P-type field effect transistor Q3, wherein the first voltage-dividing resistor includes: a sixth resistor R6 and a twenty-eighth resistor R28, wherein one end of the twenty-eighth resistor R28 is connected to one end of the sixth resistor R6, and the other end is connected to the source of the P-type field effect transistor Q3, the other end of the sixth resistor R6 is connected to pin 21 of the MCU chip 210, the drain of the P-type field effect transistor Q3 is connected to the third low-end input pin IN- of the third chip IC3, the drain of the P-type field effect transistor Q3 is also connected to the light source 100 (i.e., LED1), and the gate of the P-type field effect transistor Q3 is connected to pin 20 of the MCU chip 210.

[0092] When the fourth chip IC4 of the first light source driving circuit 300 is enabled, the fourth chip IC4 is connected to the third chip IC3, and the two series resistors of the twenty-eighth resistor R28 and the sixth resistor R6 are connected to the light source 100 (ie, LED1). When the pin 20 of the MCU chip 210 outputs a low level, the P-type field effect transistor Q3 is turned on, and the twenty-eighth resistor R28 and the sixth resistor R6 are connected to the lamp bead LED1. When the pin 20 of the MCU chip 210 outputs a high level, the P-type field effect transistor Q3 is turned off, and the twenty-eighth resistor R28 and the sixth resistor R6 are disconnected from the light source 100 (ie, LED1). The start and stop control of the light source 100 by the second light source driving circuit 400 is similar to this, and will not be described in detail here.

[0093] Specifically, in one embodiment, the control circuit 200 is powered on by a switch button to generate a conduction control signal. The conduction control signal of this embodiment changes the duty cycle of the voltage by changing the conduction frequency, thereby changing the reference voltage of the MCU chip 210. Since one end of the sixth resistor R6 is connected to the pin 21 of the MCU chip 210, after the reference voltage of the MCU chip 210 is changed, the output voltage of the sixth resistor R6 also changes, that is, the first divided voltage value obtained by the first voltage-dividing resistor (that is, the sixth resistor R6 and the twenty-eighth resistor R28) changes. The first divided voltage value is divided by the sixth resistor R6, the twenty-eighth resistor R28 and the P-type field effect transistor Q3, thereby changing the output voltage value output to the light source 100 (that is, LED1), and realizing multi-level dimming. Then the second feedback pin OUT4 of the fourth chip IC4 in the first synchronous rectification circuit 310 monitors the output voltage between the first inductor L1 and the second capacitor group (i.e., the output voltage value of the light source LED1), and feeds back the voltage monitoring result to the MCU chip 210 through the first feedback pin FB4, so that the MCU chip 210 outputs the reference voltage stably and accurately according to the dimming requirements. In this embodiment, by changing the reference voltage of the MCU chip 210, the output voltage value output to the light source 100 (i.e., LED1) is changed, that is, the working mode is a constant voltage mode. The reason for adopting the constant voltage mode is that when the current range is 0mA-500mA, it belongs to the small current range. If the constant current mode is adopted, the required brightness accuracy cannot be obtained, and the constant current mode can maintain the accuracy requirements.

[0094] In one embodiment, when the brightness adjustment signal is the second brightness adjustment signal, that is, the current range of the real-time current is 500mA-1400mA, and the working mode is the constant current mode, the working principle of the multi-level dimming is described as follows:

[0095] The first current detection circuit 320 detects the real-time current on the light source 100 and converts the real-time current into a real-time voltage. The control circuit 200 changes the second resistance value of the second voltage-dividing resistor. The first synchronous rectification circuit 310 obtains a second voltage-dividing voltage value based on the real-time voltage and the second resistance value, and changes the output voltage value output to the light source 100 based on the second voltage-dividing voltage value.

[0096] Specifically, in one embodiment, the I / O port (pin 20) of the MCU chip 210 of the control circuit 200 outputs a high level, the P-type field effect transistor Q3 is turned off, and the twenty-eighth resistor R28 and the sixth resistor R6 are disconnected from the light source 100 (i.e., LED1). The third chip IC3 of the first current detection circuit 320 monitors the output current using pins 4 and 5, and converts the output current into a real-time voltage using the third output pin OUT3. Since the first resistor R1 is connected in series with the second voltage-dividing resistor, and the first resistor R1 is connected to the third output pin OUT3, the second resistance value of the second voltage-dividing resistor is changed, and the real-time voltage can be divided to obtain the second voltage-dividing voltage value.

[0097] In this embodiment, one end of the second voltage-dividing resistor (including the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the tenth resistor R10, the eleventh resistor R11, the twelfth resistor R12, the thirteenth resistor R13 and the fifteenth resistor R15) is connected to the corresponding pin of the MCU chip 210. When the pull-up resistor (the first resistor R1) remains unchanged, the corresponding pull-down resistor (partial resistor of the second voltage-dividing resistor) is grounded through different pins of the MCU chip 210, thereby changing the second resistance value of the second voltage-dividing resistor, that is, the pull-down resistor adopts the arrangement and combination method in mathematics, and one or more resistors are selected from multiple resistors in parallel to conduct, so that the second resistance value can be transformed in multiple ways, so that the second divided voltage value under multiple transformations can be obtained according to the second resistance value.

[0098] The other end of the second voltage-dividing resistor is connected to the first feedback pin FB4 of the fourth chip IC4, so the voltage of the first feedback pin FB4 is the second voltage-dividing voltage value, thereby changing the output voltage value of the second feedback pin OUT4 of the fourth chip IC4. Since one end of the third resistor R3 is connected to the second feedback pin OUT4, and the other end of the third resistor R3 is connected to the light source 100 (i.e., LED1), the output voltage value corresponds to the voltage of the light source 100, that is, after internal transformation of the fourth chip IC4, the output voltage value is changed according to the second voltage-dividing voltage value, thereby realizing multi-level dimming of the light source 100.

[0099] In the above embodiment, the third chip IC3 of the first current detection circuit 320 monitors the output current and converts the output current into a real-time voltage. By changing the second resistance value of the second voltage-dividing resistor, the real-time voltage is divided to obtain a second divided voltage value. The output voltage value is changed according to the second divided voltage value, thereby realizing multi-level dimming of the light source 100. During the dimming process, the real-time current remains unchanged, and the real-time voltage is changed by changing the second resistance value of the second voltage-dividing resistor, that is, it is in a constant current working mode. The constant current driving method is adopted, which helps to improve the stability and service life of the LED.

[0100] In one embodiment, when the brightness adjustment signal is the third brightness adjustment signal, the second light source driving circuit 400 is used to drive the light source 100, the current range of the real-time current is 1400mA-5000mA, and the working mode is the constant current mode. At this time, the working principle of the multi-level dimming is described as follows:

[0101] The second current detection circuit 420 detects the real-time current on the light source 100 and converts the real-time current into a real-time voltage. The control circuit 200 changes the third resistance value of the third voltage-dividing resistor. The second synchronous rectification circuit 410 obtains a third voltage-dividing voltage value based on the real-time voltage and the third resistance value, and changes the output voltage value output to the light source 100 based on the third voltage-dividing voltage value.

[0102] Specifically, in one embodiment, the I / O port (pin 20) of the MCU chip 210 of the control circuit 200 outputs a high level, the P-type field effect transistor Q3 is turned off, and the twenty-eighth resistor R28 and the sixth resistor R6 are disconnected from the light source 100 (i.e., LED1). The fifth chip IC5 of the second current detection circuit 420 monitors the output current using pins 4 and 5, and converts the output current into a real-time voltage using the third output pin OUT3. Since the second resistor R2 and the third voltage-dividing resistor are connected in series, and the second resistor R2 is connected to the third output pin OUT3, the third resistance value of the third voltage-dividing resistor is changed, and the real-time voltage can be divided to obtain the third voltage-dividing voltage value.

[0103] In this embodiment, one end of the third voltage-dividing resistor (including the sixteenth resistor R16, the seventeenth resistor R17, the eighteenth resistor R18, the nineteenth resistor R19, the twentieth resistor R20, the twenty-first resistor R21, the twenty-second resistor R22 and the twenty-seventh resistor R27) is connected to the corresponding pin of the MCU chip 210. When the pull-up resistor (the second resistor R2) remains unchanged, the corresponding pull-down resistor (partial resistor of the third voltage-dividing resistor) is grounded through different pins of the MCU chip 210, thereby changing the third resistance value of the third voltage-dividing resistor, that is, the pull-down resistor adopts the arrangement and combination method in mathematics, and selects one or more resistors from multiple resistors in parallel to conduct, so that the third resistance value can be transformed in various ways, so that the third divided voltage value under various transformations can be obtained according to the change of the third resistance value.

[0104] The other end of the third voltage-dividing resistor is connected to the second feedback pin FB6 of the sixth chip IC6, so the voltage of the second feedback pin FB6 is the third voltage-dividing voltage value, thereby changing the output voltage value of the second feedback pin OUT6 of the sixth chip IC6. Since one end of the third resistor R3 is connected to the second feedback pin OUT6, and the other end of the third resistor R3 is connected to the light source 100 (i.e., LED1), the output voltage value corresponds to the voltage of the light source 100, that is, after internal conversion of the sixth chip IC6, the output voltage value is changed according to the third voltage-dividing voltage value, thereby realizing multi-level dimming of the light source 100.

[0105] In the above embodiment, the fifth chip IC5 of the second current detection circuit 420 monitors the output current and converts the output current into a real-time voltage. By changing the third resistance value of the third voltage-dividing resistor, the real-time voltage is divided to obtain a third divided voltage value. The output voltage value is changed according to the third divided voltage value, thereby realizing multi-level dimming of the light source 100. During the dimming process, the real-time current remains unchanged, and the real-time voltage is changed by changing the third resistance value of the third voltage-dividing resistor, that is, it is in a constant current working mode. The constant current driving method is adopted, which helps to improve the stability and service life of the LED.

[0106] This embodiment sets two light source driving circuits to achieve brightness adjustment of the light source within a large current adjustment range, thereby achieving stepless dimming in a wide range of brightness, improving the user experience of the stepless dimming device, and expanding the usage scenarios.

[0107] In one embodiment, the stepless dimming device also includes: a charge and discharge protection circuit 500, one end of the charge and discharge protection circuit 500 is connected to the control circuit 200, and the other end is connected to the power supply device, which is used to charge or discharge the MCU chip 210 in the control circuit 200 using the power supply device according to the charge and discharge signal sent by the control circuit 200. For example, the power supply device can be a battery.

[0108] In this embodiment, the charge and discharge protection circuit 500 is responsible for protecting the battery of the control circuit 200 when charging and discharging. The specific working principle is to limit the charging and discharging effect of the battery by using the conduction state of components such as field effect transistors or triodes, and to limit the undesirable phenomena of overcharging, overdischarging and overcurrent of the battery, thereby protecting the battery to achieve the purpose of efficient utilization.

[0109] In one embodiment, the stepless dimming device further includes: an anti-reverse connection circuit 600, one end of the anti-reverse connection circuit 600 is connected to the power supply, and the other end is connected to the charge and discharge protection circuit 500, for disconnecting the power supply when the power supply is reversely connected.

[0110] In this embodiment, the anti-reverse connection circuit 600 is responsible for disconnecting the power supply when the power supply is reversely connected. When the power supply is reversely connected, the circuit is disconnected, and the subsequent charge and discharge protection circuit 500 does not work, thereby protecting the subsequent charge and discharge protection circuit.

[0111] In one embodiment, since the current range to be output is different, different light source driving circuits are used. Different light source driving circuits correspond to different sampling resistors. Different sampling resistors can be obtained based on prior knowledge or debugging during use. The combination of the first current driving circuit and the second current driving circuit can cover a wide range of currents, thereby achieving a wide range of brightness adjustment. In one embodiment, the inductance value of the first inductor L1 is 1uH, the resistance value of the twenty-eighth resistor R28 is 10KΩ, the resistance value of the first resistor R1 is 10KΩ, the second resistor R2 is 10KΩ, the inductance value of the second inductor L2 is 0.47uH, and the sixth capacitor C6 is 10 5 F, the eighth capacitor C8 is 10 5 F, the resistance value of the third resistor R3 is 60mΩ, the resistance value of the fourth resistor R4 is 10mΩ, and the resistance value of the fifth resistor R5 is 10mΩ.

[0112] Reference Figure 4 , is a schematic diagram of a stepless dimming device according to an embodiment of the present application.

[0113] Figure 4In the embodiment, the stepless dimming device includes: a light source (i.e., LED1 in the figure), a control circuit 200, a light source driving circuit 700, a charge and discharge protection circuit 500, and an anti-reverse connection circuit 600, as well as peripheral circuits of the corresponding circuits. The light source driving circuit 700 includes: a first light source driving circuit 300 and a second light source driving circuit 400. The anti-reverse connection circuit is connected to the charge and discharge protection circuit, the charge and discharge protection circuit is connected to the control circuit 200, the control circuit 200 is connected to the light source driving circuit, and the light source driving circuit is connected to the light source. Specifically, the control circuit 200 generates a start and stop signal to control the start and stop of the light source and generates a brightness adjustment signal to adjust the brightness of the light source. The first light source driving circuit 300 is connected to the light source and the control circuit 200, and adjusts the real-time current of the light source according to the first brightness adjustment signal or the second brightness adjustment signal; the second light source driving circuit 400 is connected to the light source and the control circuit 200, and adjusts the real-time current of the light source according to the second brightness adjustment signal. This embodiment sets two light source driving circuits, and through the combination of multiple IC chips, realizes brightness adjustment of the light source within a large current adjustment range, thereby performing multi-level adjustment of the brightness of the light source, realizing stepless dimming in a wide range of brightness, improving the user experience of the stepless dimming device, and expanding the usage scenarios.

[0114] A second aspect of the embodiments of the present invention provides a stepless dimming device, including: a stepless dimming device according to any one embodiment of the first aspect of the present invention.

[0115] In one embodiment, the stepless dimming device may be a lighting device, such as a desk lamp, a ceiling lamp, a headlamp, a miner's lamp, or a flashlight, etc., which can realize stepless dimming of a wide range of brightness of the lighting device and adapt to the application of more scenarios.

[0116] In one embodiment, the stepless dimming device is a flashlight, which is a portable lighting tool and is widely used in life. For example, a strong light flashlight is often used for lighting work in outdoor adventures, industrial maintenance and other activities, and is widely used. Currently, most flashlights are dimmable flashlights, or use a switch button or switch installed on the tail cover, or rotate the flashlight to achieve a step dimming function. The flashlight of this embodiment can achieve stepless dimming in a large brightness range and is more widely used.

[0117] A third aspect of the embodiments of the present invention provides a stepless dimming control method, which is applied to the stepless dimming device as described in any one of the first aspects, referring to Figure 5 The method includes steps S510 to S530:

[0118] Step S510: generating a brightness adjustment signal according to the brightness range operation instruction.

[0119] Step S520: sending a first brightness adjustment signal or a second brightness adjustment signal to the first light source driving circuit to adjust the brightness of the light source.

[0120] Step S530: Sending a third brightness adjustment signal to the second light source driving circuit to adjust the brightness of the light source.

[0121] It can be seen that the contents of the above-mentioned stepless dimming device embodiment are all applicable to the embodiment of the stepless dimming control method of this embodiment. The functions specifically implemented by this usage method embodiment are the same as those of the above-mentioned stepless dimming device embodiment, and the beneficial effects achieved are also the same as those achieved by the above-mentioned stepless dimming device embodiment.

[0122] The above described embodiments are merely illustrative, and the units described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0123] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and conciseness of description, only the specific circuit structure of each circuit module divided above is illustrated by example. In actual applications, different specific circuit structures can be adopted for each circuit module as needed, and all or part of the functions described above can be completed by adding some electronic components, changing the connection method of some electronic components, and replacing some electronic components.

[0124] Those skilled in the art will appreciate that all or some of the steps and systems in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit.

[0125] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A stepless dimming device, It is characterized in that include: light source; a control circuit, configured to generate a brightness adjustment signal according to a brightness range operation instruction, wherein when the brightness range operation instruction is a first brightness range operation instruction, the brightness adjustment signal is a first brightness adjustment signal, when the brightness range operation instruction is a second brightness range operation instruction, the brightness adjustment signal is a second brightness adjustment signal, and when the brightness range operation instruction is a third brightness range operation instruction, the brightness adjustment signal is a third brightness adjustment signal; The first brightness adjustment signal includes: a first current range signal and a constant voltage mode signal, the second brightness adjustment signal includes: a second current range signal and a constant current mode signal, and the third brightness adjustment signal includes: a third current range signal and a constant current mode signal; the first brightness range is smaller than the second brightness range, the second brightness range is smaller than the third brightness range, the first current range is smaller than the second current range, and the second current range is smaller than the third current range; a first light source driving circuit connected to the light source and the control circuit, and configured to adjust the brightness of the light source according to the first brightness adjustment signal or the second brightness adjustment signal; a second light source driving circuit, connected to the light source and the control circuit, and configured to adjust the brightness of the light source according to the third brightness adjustment signal; The first light source driving circuit comprises: a first current detection circuit, connected to the first synchronous rectification circuit and the light source, and used for detecting the real-time current of the light source; a first feedback circuit, connected to the control circuit and the first current detection circuit, and configured to change an output voltage value of the light source according to the first brightness adjustment signal; The first synchronous rectification circuit is connected to the control circuit and is used to send the output voltage value to the control circuit, or to change the output voltage value of the light source according to the real-time current; The second light source driving circuit comprises: a second current detection circuit, connected to the second synchronous rectification circuit and the light source, and used for detecting the real-time current of the light source; a second feedback circuit, connected to the control circuit and the second current detection circuit, and configured to obtain a real-time current of the light source according to the third brightness adjustment signal; The second synchronous rectification circuit is connected to the control circuit and is used for changing the output voltage value of the light source according to the real-time current.

2. The stepless dimming device according to claim 1, It is characterized in that The first feedback circuit includes a first voltage-dividing resistor. When the brightness adjustment signal is a first brightness adjustment signal: The control circuit is used to generate a conduction control signal to change the first divided voltage value of the first divided voltage resistor; The first feedback circuit is used to change the output voltage value output to the light source according to the first divided voltage value; The first synchronous rectification circuit is used to feed back the output voltage value to the control circuit, so that the control circuit changes the conduction control signal according to the output voltage value of the light source.

3. The stepless dimming device according to claim 1, It is characterized in that The first feedback circuit includes a second voltage-dividing resistor, and when the brightness adjustment signal is a second brightness adjustment signal: The first current detection circuit is used to detect the real-time current of the light source and convert the real-time current into a real-time voltage; The control circuit is used to change the second resistance value of the second voltage-dividing resistor; The first synchronous rectification circuit is used for obtaining a second divided voltage value according to the real-time voltage and the second resistance value, and changing an output voltage value output to the light source according to the second divided voltage value.

4. The stepless dimming device according to claim 1, It is characterized in that The second feedback circuit includes a third voltage-dividing resistor. When the brightness adjustment signal is a third brightness adjustment signal: The second current detection circuit is used to detect the real-time current on the light source and convert the real-time current into a real-time voltage; The control circuit is used to change the third resistance value of the third voltage-dividing resistor; The second synchronous rectification circuit is used for obtaining a third divided voltage value according to the real-time voltage and the third resistance value, and changing an output voltage value output to the light source according to the third divided voltage value.

5. A stepless dimming device according to any one of claims 1 to 4, It is characterized in that The stepless dimming device also includes: A charge and discharge protection circuit has one end connected to the control circuit and the other end connected to the power supply device, and is used to charge or discharge the power supply device according to the charge and discharge signal sent by the control circuit.

6. The stepless dimming device according to claim 5, It is characterized in that The stepless dimming device also includes: The anti-reverse connection circuit has one end connected to the power supply and the other end connected to the charge and discharge protection circuit, and is used to disconnect the power supply when the power supply is reversely connected.

7. A stepless dimming control method, It is characterized in that Applied to the stepless dimming device according to any one of claims 1 to 6, the method comprises: Generate a brightness adjustment signal according to the brightness range operation instruction; Sending the first brightness adjustment signal or the second brightness adjustment signal to the first light source driving circuit to adjust the brightness of the light source; The third brightness adjustment signal is sent to the second light source driving circuit to adjust the brightness of the light source.

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