Constant current source driving circuit of laser

Abstract

The utility model discloses a constant current source drive circuit of a laser, which comprises a switching power supply, a laser pumping source, a constant current source circuit, a switching circuit and a power control circuit, the output end of the switching power supply is connected with the input end of the laser pumping source, the output end of the laser pumping source is connected with the input end of the constant current source circuit, and the output end of the constant current source circuit is grounded; the first input end of the switching circuit is used for acquiring a switching control signal, the second input end of the switching circuit is connected with the output end of the power control circuit, the third input end of the switching circuit is used for acquiring a negative voltage driving signal, and the output end of the switching circuit is connected with the control end of the constant current source circuit; the switching circuit is used for controlling the third input end of the switching circuit to be disconnected from the output end of the switching circuit and controlling the second input end of the switching circuit to be connected with the output end of the switching circuit according to a switching control signal in a power-on stage; the problem that an existing constant current source drive circuit leaks light in the system power-on period is solved.

Description

Technical Field

[0001] The utility model relates to the field of laser control, in particular to a constant current source drive circuit for a laser. Background Technique

[0002] As Figure 1 shown, the existing constant current source drive circuit of a laser generally consists of a switching power supply 20, a laser pump source 21, a constant current source circuit 22, and a system power control circuit 23. Among them, the switching power supply 20 converts the mains AC voltage into direct current, and the specific DC voltage amplitude is determined according to the rated working voltage of the used laser pump source and the number of series-connected branches; the laser pump source 21 converts electrical energy into light energy, and multiple pump sources can be used in series; the constant current source circuit 22 controls the current of the pump source according to the power control setting. When the power control setting is constant, the current of the pump source is also constant. The implementation principle of this constant current source circuit 22 is to control the conduction resistance of the MOSFET through a negative feedback and integral circuit to adjust the magnitude of the current. The power control circuit 23 outputs an analog signal from the DAC, which is given to the constant current source after passing through a voltage follower operational amplifier to control the magnitude of the current of the constant current source.

[0003] When Figure 1 the constant current source drive circuit in Summary of the Invention

[0004] An embodiment of the utility model provides a constant current source drive circuit for a laser to solve the problem of light leakage existing in the existing constant current source drive circuit during system power-on.

[0005] In one embodiment, a constant current source drive circuit for a laser is provided. The constant current source drive circuit includes:

[0006] A switching power supply, a laser pump source, a constant current source circuit, a switching circuit, and a power control circuit. The output end of the switching power supply is connected to the input end of the laser pump source, the output end of the laser pump source is connected to the input end of the constant current source circuit, and the output end of the constant current source circuit is grounded;

[0007] The first input end of the switching circuit is used to obtain a switching control signal, the second input end of the switching circuit is connected to the output end of the power control circuit, the third input end of the switching circuit is used to obtain a negative voltage drive signal, and the output end of the switching circuit is connected to the control end of the constant current source circuit;

[0008] The switching circuit is used to, during the power-on phase, control the third input terminal of the switching circuit to disconnect from the output terminal of the switching circuit according to the switching control signal, and control the second input terminal of the switching circuit to connect with the output terminal of the switching circuit.

[0009] In one embodiment, the constant current source drive circuit further includes:

[0010] A voltage detection circuit is provided, wherein the input terminal of the voltage detection circuit is connected to the output terminal of the switching power supply, and the output terminal of the voltage detection circuit is connected to the first input terminal of the switching circuit. The voltage detection circuit is used to output the switching control signal.

[0011] In one embodiment, the voltage detection circuit includes:

[0012] The circuit includes a current-limiting resistor and a clamping module. The input terminal of the current-limiting resistor serves as the input terminal of the voltage detection circuit, and the output terminal of the current-limiting resistor is connected to the clamping terminal of the clamping module. The clamping terminal of the clamping module serves as the output terminal of the voltage detection circuit.

[0013] In one embodiment, the clamping module includes:

[0014] The clamping diode, the first capacitor, and the load resistor are configured such that the cathode of the clamping diode serves as the clamping terminal of the clamping module, the anode of the clamping diode is connected to ground, the first capacitor is connected in parallel with the clamping diode, and the load resistor is connected in parallel with the clamping diode.

[0015] In one embodiment, the voltage detection circuit includes:

[0016] An analog-to-digital converter (ADC) and a processor are provided, wherein the input terminal of the ADC serves as the input terminal of the voltage detection circuit, the output terminal of the ADC is connected to the input terminal of the processor, and the output terminal of the processor serves as the output terminal of the voltage detection circuit.

[0017] In one embodiment, the switching circuit includes:

[0018] An analog switch chip is provided, wherein the enable terminal of the analog switch chip serves as the first input terminal of the switching circuit, the first input terminal of the analog switch chip serves as the second input terminal of the switching circuit, and the second input terminal of the analog switch chip serves as the third input terminal of the switching circuit.

[0019] In one embodiment, the power control circuit includes:

[0020] A digital-to-analog converter (DAC) and a follower are provided. The input terminal of the DAC serves as the input terminal of the power control circuit, and the output terminal of the DAC is connected to the input terminal of the follower. The output terminal of the follower serves as the output terminal of the power control circuit.

[0021] In one embodiment, the constant current source circuit includes:

[0022] The system includes a comparator, a drive switch, a voltage divider module, a feedback module, and a current detection module. The first input terminal of the comparator is used to obtain the output signal of the output terminal of the switching circuit. The second input terminal of the comparator is connected to the output terminal of the feedback module, and the output terminal of the comparator is connected to the first input terminal of the feedback module.

[0023] The output of the comparator is connected to the input of the voltage divider module, the output of the voltage divider module is grounded, the voltage divider terminal of the voltage divider module is connected to the control terminal of the drive switch, the input of the drive switch serves as the input of the constant current source circuit, the output of the drive switch is connected to the input of the current detection module, and the output of the current detection module is connected to the second input of the feedback module.

[0024] In one embodiment, the feedback module includes:

[0025] A first resistor R7, a second resistor R8, and a second capacitor C1 are connected. The input terminal of the first resistor serves as the second input terminal of the feedback module. The output terminal of the first resistor is connected to the output terminal of the second resistor, and the output terminal of the second resistor serves as the output terminal of the feedback module. The input terminal of the second resistor is connected to the output terminal of the second capacitor, and the input terminal of the second capacitor serves as the first input terminal of the feedback module.

[0026] In one embodiment, the voltage divider module includes:

[0027] The third resistor R4 and the fourth resistor R5 are connected. The input terminal of the third resistor serves as the input terminal of the voltage divider module, and the output terminal of the third resistor is connected to the input terminal of the fourth resistor. The input terminal of the fourth resistor serves as the voltage divider terminal of the voltage divider module, and the output terminal of the fourth resistor serves as the output terminal of the voltage divider module.

[0028] The current detection module includes a detection resistor, the input terminal of which serves as the input terminal of the current detection module, and the output terminal of which serves as the output terminal of the current detection module.

[0029] This utility model embodiment provides a constant current source driving circuit for a laser. During system power-up, a switching circuit controls the third input terminal of the switching circuit to disconnect from the output terminal of the switching circuit based on a switching control signal characterizing the output voltage of the switching power supply, and controls the second input terminal of the switching circuit to connect with the output terminal of the switching circuit. This achieves the switching of the signal input from the control terminal of the constant current source circuit from a negative voltage driving signal to a high-level driving signal output by the power control circuit, thereby preventing leakage of the constant current source driving circuit during power-up. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of a constant current source drive circuit for a laser in the prior art;

[0032] Figure 2 The waveforms of the power supply voltage V (VDD), drive voltage V (VG), current I (RCS), and comparator supply voltage V (VCC) of the constant current source drive circuit in the prior art are shown.

[0033] Figure 3 This is a schematic diagram of the constant current source driving circuit of the laser in one embodiment of the present invention;

[0034] Figure 4 This is a waveform diagram of the power supply voltage V (VDD), driving voltage V (VG), current I (RCS), and comparator power supply voltage V (VCC) of the constant current source driving circuit in one embodiment of this utility model.

[0035] Figure 5 This is a schematic diagram of a voltage detection circuit in one embodiment of the present invention;

[0036] The labeling is explained as follows:

[0037] 20. Switching power supply for existing constant current source drive circuit; 21. Laser pump source for existing constant current source drive circuit; 22. Constant current source circuit for existing constant current source drive circuit; 23. Power control circuit for existing constant current source drive circuit; 10. Switching power supply; 11. Laser pump source; 12. Constant current source circuit; 13. Power control circuit; 14. Voltage detection circuit; 15. Switching circuit. Detailed Implementation

[0038] The applicant discovered through research that Figure 1 The reason for light leakage during power-up in the constant current source drive circuit is that the input bias voltage of the comparator in the constant current source circuit 22 and the input bias voltage of the follower in the system power control circuit 23 are less than 0V, causing the comparator in the constant current source circuit 22 to output a linearly increasing voltage V(VG), such as... Figure 2 The voltage waveform V(VG) shown eventually reaches operational amplifier saturation, outputting a saturation voltage of approximately 12V. This saturation voltage is then supplied to the control terminal of the drive switch in the constant current source circuit 22, at which point the drive switch is fully turned on. When the voltage V(VDD) of the switching power supply 20 reaches the minimum operating voltage of the laser pump source 21, the constant current source circuit 22 outputs a pulse current, such as... Figure 2 The current waveform I(RCS) output by the constant current source circuit 22 at a time of 10ms on the horizontal axis is the pulse current. It is this pulse current that causes the pump source to emit laser light, which means that the constant current source drive circuit has an unacceptable light leakage problem during power-on.

[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0040] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. In the drawings, for clarity, the dimensions of layers and regions, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.

[0041] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this utility model, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0042] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0043] In one embodiment, such as Figure 3 As shown, a constant current source driving circuit for a laser is provided, the constant current source driving circuit comprising:

[0044] The system includes a switching power supply 10, a laser pump source 11, a constant current source circuit 12, a switching circuit 15, and a power control circuit 13. The output terminal of the switching power supply 10 is connected to the input terminal of the laser pump source 11, the output terminal of the laser pump source 11 is connected to the input terminal of the constant current source circuit 12, and the output terminal of the constant current source circuit 12 is grounded.

[0045] The first input terminal of the switching circuit 15 is used to acquire a switching control signal, the second input terminal of the switching circuit 15 is connected to the output terminal of the power control circuit 13, the third input terminal of the switching circuit 15 is used to acquire a negative voltage drive signal, and the output terminal of the switching circuit 15 is connected to the control terminal of the constant current source circuit 12.

[0046] The switching circuit 15 is used to, during the power-on phase, control the third input terminal of the switching circuit to disconnect from the output terminal of the switching circuit according to the switching control signal, and control the second input terminal of the switching circuit to connect with the output terminal of the switching circuit.

[0047] The constant current source drive circuit works as follows:

[0048] The switching power supply 10 converts AC mains voltage to DC voltage. The specific DC voltage amplitude is determined by the rated operating voltage of the laser pump source 11 and the number of pump sources connected in series. The laser pump source 11 converts electrical energy into light energy, and multiple pump sources can be used in series. The constant current source circuit 12 controls the pump source current based on the output of the power control circuit 13. When the signal voltage output by the power control circuit 13 is constant, the pump source current is also constant. The constant current source circuit 12 adjusts the current magnitude by controlling the on-resistance of the drive switch. The power control circuit 13 outputs an analog signal to the constant current source circuit 12 to control the magnitude of the constant current source current.

[0049] When the switching control signal acquired by the switching circuit 15 is a low-level signal, the third input terminal of the switching circuit 15 is connected to the output terminal of the switching circuit 15, and the driving voltage V (VG) acquired by the control terminal of the driving switch in the constant current source circuit 12 is 0V (i.e., a low-level signal). Figure 4 As shown; when the switching control signal acquired by the switching circuit 15 is a high-level signal, the connection between the third input terminal and the output terminal of the switching circuit 15 is switched to the connection between the second input terminal and the output terminal of the switching circuit 15. Only then does the driving voltage V (VG) output by the constant current source circuit 12 become a high-level driving signal. However, at this time, the constant current source driving circuit has already completed system power-on. That is, during the system power-on period of the constant current source driving circuit, the driving switch in the constant current source circuit 12 remains in the open state. There is no pulse current in the current I (RCS) output by the constant current source circuit 12, so it will not drive the pump source to emit laser light, thus avoiding the light leakage problem of the constant current source driving circuit during power-on.

[0050] In this embodiment, the constant current source drive circuit utilizes the switching circuit 15 to control the third input terminal of the switching circuit to disconnect from the output terminal of the switching circuit, and control the second input terminal of the switching circuit to connect with the output terminal of the switching circuit, based on a switching control signal characterizing the output voltage of the switching power supply 10 during system power-up. This achieves the switching of the signal input from the control terminal of the constant current source circuit 12 from a negative voltage drive signal to a high-level drive signal output by the power control circuit 13, thereby preventing leakage current in the constant current source drive circuit during power-up. For example, as shown... Figure 3As shown, the first input terminal (pin 6) of the switching circuit 15 is used to obtain the switching control signal, the second input terminal (pin 1) of the switching circuit 15 is connected to the output terminal (OUT) of the power control circuit 13, the third input terminal (pin 3) of the switching circuit 15 is used to obtain the negative voltage drive signal, and the output terminal (pin 4) of the switching circuit 15 is connected to the control terminal of the constant current source circuit 12.

[0051] In one embodiment, such as Figure 3 As shown, the constant current source drive circuit further includes:

[0052] A voltage detection circuit 14 is provided, the input of which is connected to the output of the switching power supply 10, and the output of which is connected to the first input (pin 6) of the switching circuit 15. The voltage detection circuit 14 is used to output the switching control signal.

[0053] The voltage detection circuit 14 detects the output voltage of the switching power supply 10 and outputs a switching control signal to the first input terminal (pin 6) of the switching circuit 15. When the output voltage of the switching power supply 10 rises to the rated voltage, the switching control signal output by the voltage detection circuit 14 is a high-level drive signal.

[0054] In one embodiment, such as Figure 3 As shown, the voltage detection circuit 14 includes:

[0055] The circuit includes a current-limiting resistor and a clamping module. The input terminal of the current-limiting resistor serves as the input terminal of the voltage detection circuit 14, and the output terminal of the current-limiting resistor is connected to the clamping terminal of the clamping module. The clamping terminal of the clamping module serves as the output terminal of the voltage detection circuit 14.

[0056] In one embodiment, such as Figure 3 As shown, the clamping module includes:

[0057] The clamping diode, the first capacitor, and the load resistor are configured such that the cathode of the clamping diode serves as the clamping terminal of the clamping module, the anode of the clamping diode is connected to ground, the first capacitor is connected in parallel with the clamping diode, and the load resistor is connected in parallel with the clamping diode.

[0058] When the switching power supply 10 starts outputting voltage upon power-up, the cathode of the clamping diode provides the clamping voltage for the clamping module. Because the rise time of the output voltage VDD varies for different switching power supplies 10, a suitable value for the first capacitor can be selected to adjust the rise time of the clamping voltage, ultimately causing the output voltage VDD to rise to the rated voltage. Figure 4 The clamping voltage V(SW) in the circuit is a high-level amplitude, and the switching control signal obtained by the switching circuit 15 is a high-level drive signal.

[0059] In one embodiment, such as Figure 5 As shown, the voltage detection circuit 14 includes:

[0060] The system includes an analog-to-digital converter (ADC) and a processor (MCU). The input terminal of the ADC serves as the input terminal of the voltage detection circuit 14, and the output terminal of the ADC is connected to the input terminal of the processor. The output terminal of the processor serves as the output terminal of the voltage detection circuit 14.

[0061] The input terminal of the analog-to-digital converter is used to acquire the output voltage of the switching power supply 10 and send it to the processor. The processor then outputs a switching control signal SW to the switching circuit 15 after determining the voltage.

[0062] In one embodiment, such as Figure 3 As shown, the switching circuit 15 includes:

[0063] The analog switch chip U2 has its enable terminal IN serving as the first input terminal (pin 6) of the switching circuit 15, its first input terminal NO serving as the second input terminal (pin 1) of the switching circuit 15, and its second input terminal NC serving as the third input terminal (pin 3) of the switching circuit 15.

[0064] Specifically, the analog switch chip can be a single-pole double-throw switch. When the switching control signal SW acquired by the enable terminal IN of the analog switch chip is a high-level drive signal, the first input terminal NO of the analog switch chip U2 is connected to the output terminal COM of the analog switch chip. The drive signal VCMD from the power control circuit 13 is then output to the output terminal COM through the first input terminal NO of the analog switch chip U2 and sent to the constant current source circuit 12. When the switching control signal SW acquired by the enable terminal IN of the analog switch chip is a low-level drive signal, the second input terminal NC of the analog switch chip U2 is connected to the output terminal COM of the analog switch chip. The negative voltage drive signal V2 is then output to the constant current source circuit 12 through the second input terminal NC. The amplitude of the negative voltage drive signal is determined based on the input bias voltage of the comparator in the constant current source circuit 12 and the input bias voltage of the follower in the power control circuit 13. In practical applications, it can be determined based on the output voltage of the follower in the power control circuit 13 when the system is powered on. The voltage amplitude of the negative voltage drive signal is adjusted so that the output voltage of the follower is less than the opening threshold voltage of the drive switch.

[0065] In one embodiment, such as Figure 3 As shown, the power control circuit 13 includes:

[0066] The digital-to-analog converter (DAC) and a follower are provided. The input terminal of the DAC serves as the input terminal of the power control circuit 13, the output terminal of the DAC is connected to the input terminal of the follower, and the output terminal of the follower serves as the output terminal of the power control circuit 13.

[0067] The digital-to-analog converter is used to output an analog signal, the follower is used to stabilize the voltage amplitude of the analog signal, and outputs a stable drive signal VCMD.

[0068] In one embodiment, such as Figure 3 As shown, the constant current source circuit 12 includes:

[0069] The system includes a comparator, a drive switch, a voltage divider module, a feedback module, and a current detection module. The first input terminal of the comparator is used to obtain the output signal of the output terminal (pin 4) of the switching circuit 15. The second input terminal of the comparator is connected to the output terminal of the feedback module, and the output terminal of the comparator is connected to the first input terminal of the feedback module.

[0070] The output terminal of the comparator is connected to the input terminal of the voltage divider module, the output terminal of the voltage divider module is grounded, the voltage divider terminal of the voltage divider module is connected to the control terminal of the drive switch, the input terminal of the drive switch serves as the input terminal of the constant current source circuit 12, the output terminal of the drive switch is connected to the input terminal of the current detection module, and the output terminal of the current detection module is connected to the second input terminal of the feedback module.

[0071] The feedback module is used to feed back the electrical signal from the output of the comparator and the electrical signal from the output of the current detection module to the second input of the comparator, adjust the driving voltage V (VG) output by the output of the comparator, and then control the on-resistance of the drive switch to adjust the current.

[0072] In one embodiment, such as Figure 3 As shown, the feedback module includes:

[0073] A first resistor R7, a second resistor R8, and a second capacitor C1 are connected. The input terminal of the first resistor serves as the second input terminal of the feedback module. The output terminal of the first resistor is connected to the output terminal of the second resistor, and the output terminal of the second resistor serves as the output terminal of the feedback module. The input terminal of the second resistor is connected to the output terminal of the second capacitor, and the input terminal of the second capacitor serves as the first input terminal of the feedback module.

[0074] In one embodiment, such as Figure 3 As shown, the voltage divider module includes:

[0075] The third resistor R4 and the fourth resistor R5 are connected. The input terminal of the third resistor serves as the input terminal of the voltage divider module, and the output terminal of the third resistor is connected to the input terminal of the fourth resistor. The input terminal of the fourth resistor serves as the voltage divider terminal of the voltage divider module, and the output terminal of the fourth resistor serves as the output terminal of the voltage divider module.

[0076] The current detection module includes a detection resistor, the input terminal of which serves as the input terminal of the current detection module, and the output terminal of which serves as the output terminal of the current detection module.

[0077] Figure 3 The constant current source drive circuit shown prevents laser light leakage by switching the electrical signal at the control terminal of the drive switch in the constant current source circuit 12 from a negative voltage drive signal to a high-level drive signal output by the power control circuit 13 during the system power-on phase; simulation results are as follows. Figure 3 As shown, before the switching power supply 10 outputs the rated voltage, the electrical signal voltage value of the comparator output to the control terminal of the drive switch is always 0V; after the switching power supply 10 outputs the rated voltage, the electrical signal voltage value VG output by the comparator to the control terminal of the drive switch is less than the threshold voltage of the switch; during the entire system power-on process, the current of the sampling resistor RCS is close to 0, which is less than the minimum operating current of the pump source, thereby preventing the laser from leaking light when powered on.

[0078] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.

Claims

1. A constant current source driving circuit for a laser, characterized in that, The constant current source driving circuit includes: The system includes a switching power supply, a laser pump source, a constant current source circuit, a switching circuit, and a power control circuit. The output terminal of the switching power supply is connected to the input terminal of the laser pump source, the output terminal of the laser pump source is connected to the input terminal of the constant current source circuit, and the output terminal of the constant current source circuit is grounded. The first input terminal of the switching circuit is used to acquire a switching control signal, the second input terminal of the switching circuit is connected to the output terminal of the power control circuit, the third input terminal of the switching circuit is used to acquire a negative voltage drive signal, and the output terminal of the switching circuit is connected to the control terminal of the constant current source circuit. The switching circuit is used to, during the power-on phase, control the third input terminal of the switching circuit to disconnect from the output terminal of the switching circuit according to the switching control signal, and control the second input terminal of the switching circuit to connect with the output terminal of the switching circuit.

2. The constant current source driving circuit according to claim 1, characterized in that, The constant current source driving circuit further includes: A voltage detection circuit is provided, wherein the input terminal of the voltage detection circuit is connected to the output terminal of the switching power supply, and the output terminal of the voltage detection circuit is connected to the first input terminal of the switching circuit. The voltage detection circuit is used to output the switching control signal.

3. The constant current source driving circuit according to claim 2, characterized in that, The voltage detection circuit includes: The circuit includes a current-limiting resistor and a clamping module. The input terminal of the current-limiting resistor serves as the input terminal of the voltage detection circuit, and the output terminal of the current-limiting resistor is connected to the clamping terminal of the clamping module. The clamping terminal of the clamping module serves as the output terminal of the voltage detection circuit.

4. The constant current source driving circuit according to claim 3, characterized in that, The clamping module includes: The clamping diode, the first capacitor, and the load resistor are configured such that the cathode of the clamping diode serves as the clamping terminal of the clamping module, the anode of the clamping diode is connected to ground, the first capacitor is connected in parallel with the clamping diode, and the load resistor is connected in parallel with the clamping diode.

5. The constant current source driving circuit according to claim 2, characterized in that, The voltage detection circuit includes: An analog-to-digital converter (ADC) and a processor are provided, wherein the input terminal of the ADC serves as the input terminal of the voltage detection circuit, the output terminal of the ADC is connected to the input terminal of the processor, and the output terminal of the processor serves as the output terminal of the voltage detection circuit.

6. The constant current source driving circuit according to any one of claims 1 to 5, characterized in that, The switching circuit includes: An analog switch chip is provided, wherein the enable terminal of the analog switch chip serves as the first input terminal of the switching circuit, the first input terminal of the analog switch chip serves as the second input terminal of the switching circuit, and the second input terminal of the analog switch chip serves as the third input terminal of the switching circuit.

7. The constant current source driving circuit according to claim 1, characterized in that, The power control circuit includes: A digital-to-analog converter (DAC) and a follower are provided. The input terminal of the DAC serves as the input terminal of the power control circuit, and the output terminal of the DAC is connected to the input terminal of the follower. The output terminal of the follower serves as the output terminal of the power control circuit.

8. The constant current source driving circuit according to claim 1, characterized in that, The constant current source circuit includes: The system includes a comparator, a drive switch, a voltage divider module, a feedback module, and a current detection module. The first input terminal of the comparator is used to obtain the output signal of the output terminal of the switching circuit. The second input terminal of the comparator is connected to the output terminal of the feedback module, and the output terminal of the comparator is connected to the first input terminal of the feedback module. The output of the comparator is connected to the input of the voltage divider module, the output of the voltage divider module is grounded, the voltage divider terminal of the voltage divider module is connected to the control terminal of the drive switch, the input of the drive switch serves as the input of the constant current source circuit, the output of the drive switch is connected to the input of the current detection module, and the output of the current detection module is connected to the second input of the feedback module.

9. The constant current source driving circuit according to claim 8, characterized in that, The feedback module includes: A first resistor, a second resistor, and a second capacitor are provided. The input terminal of the first resistor serves as the second input terminal of the feedback module. The output terminal of the first resistor is connected to the output terminal of the second resistor, and the output terminal of the second resistor serves as the output terminal of the feedback module. The input terminal of the second resistor is connected to the output terminal of the second capacitor, and the input terminal of the second capacitor serves as the first input terminal of the feedback module.

10. The constant current source driving circuit according to claim 8, characterized in that, The voltage divider module includes: The third resistor and the fourth resistor, the input terminal of the third resistor serves as the input terminal of the voltage divider module, the output terminal of the third resistor is connected to the input terminal of the fourth resistor, and the input terminal of the fourth resistor serves as the voltage divider terminal of the voltage divider module, and the output terminal of the fourth resistor serves as the output terminal of the voltage divider module; The current detection module includes a detection resistor, the input terminal of which serves as the input terminal of the current detection module, and the output terminal of which serves as the output terminal of the current detection module.

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