A pulse constant current control circuit

Abstract

The present invention discloses a pulse constant current control circuit, wherein a pulse current sampling resistor is arranged between the ground terminal of a power constant current control switch and the negative electrode of a DC power supply for collecting a negative pulse voltage proportional to the pulse current, and its output terminal is connected to the input terminal of a pulse current constant current drive signal forming circuit; the pulse current reference forming circuit is used to generate a pulse current control pulse voltage reference, and its output terminal is connected to the input terminal of a pulse current constant current drive signal forming circuit, and the pulse current constant current drive signal forming circuit is used to generate an error signal according to the pulse voltage reference and the negative pulse voltage obtained by sampling the pulse current, and its output terminal is connected to a follow-up drive and protection circuit, and the follow-up drive and protection circuit is used to drive and control the power constant current control switch to realize pulse constant current control. The control circuit of the present invention is reliable and can control the generation of stable constant current pulses.

Description

Technical Field

[0001] The invention relates to the field of switch power supply drive control, and in particular to a pulse constant current control circuit. Background Art

[0002] With the continuous updating and rapid development of switching power supply technology, as well as the miniaturization, high frequency and high reliability of high-power semiconductor devices, high-voltage pulse power technology has been widely used in many fields such as accelerators, radar transmitters, safety inspections, industrial non-destructive testing, military laser weapons, etc. Developed countries are competing to develop high-voltage pulse power application technology, especially DPSSL technology, and the key one is pulse constant current control and regulation technology, so as to better meet the requirements of special indicators such as output pulse waveform quality of the power supply.

[0003] However, generally, positive return pulse current sampling and pulse voltage reference are used to form a pulse constant current control PID regulation drive through a voltage error amplifier to form a pulse constant current source. The pulse current sampling resistor of this drive circuit is dissolved into the drive pole of the power constant current control switch (such as IGBT / MOS tube), which brings some unstable factors to the circuit, etc., and the drive control circuit of the prior art cannot achieve better current stability control. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a pulse constant current control circuit, in which a sampling resistor is connected between a reference ground and the negative pole of a DC voltage to perform current sampling and a corresponding circuit is set to realize accurate and reliable drive control of a power constant current control switch.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a pulse constant current control circuit, including a pulse current sampling resistor, a pulse current reference forming circuit, a pulse current constant current drive signal forming circuit and a follow-up drive and protection circuit, wherein the pulse current sampling resistor is arranged between the ground terminal of the power constant current control switch and the negative pole of the DC power supply for collecting a negative pulse voltage proportional to the pulse current, and its output end is connected to the input end of the pulse current constant current drive signal forming circuit; the pulse current reference forming circuit is used to generate a pulse current control pulse voltage reference, and its output end is connected to the input end of the pulse current constant current drive signal forming circuit, and the pulse current constant current drive signal forming circuit is used to generate an error signal according to the pulse voltage reference and the negative pulse voltage obtained by pulse current sampling, and its output end is connected to the follow-up drive and protection circuit, and the follow-up drive and protection circuit is used to drive and control the power constant current control switch to realize pulse constant current control.

[0006] The pulse current sampling resistor includes a resistor R20; the G pole of the power constant current control switch is connected to the output end of the follower drive and protection circuit; the C pole is connected to the positive pole DC+ of the power supply through the load LD1; the E pole is grounded; one end of the resistor R20 is connected between the E pole of the power constant current control switch and the ground; the other end leads to a terminal connected to the input end of the current constant current drive signal forming circuit.

[0007] The pulse current reference forming circuit includes an optocoupler isolation driver N5, a MOS tube V9, a pulse control signal PLUS, a current adjustment reference I_ADJ, and a common-mode amplifier circuit. The pulse control signal PLUS is connected to the input end of the optocoupler isolation driver, and the output end of the optocoupler isolation driver N5 is connected to the G pole of the MOS tube V9. The G pole of V9 is connected to the cathode of the diode V12 through a resistor R17, the anode of the diode V12 is connected to the S pole of V9, and the cathode of the diode V12 is connected to a -5V power supply; the D pole of V9 is connected to the common-mode input end of the common-mode amplifier circuit and the current adjustment reference I_ADJ is input to the common-mode input end of the common-mode amplifier circuit; the common-mode amplifier circuit performs common-mode amplification on the input signal to obtain the pulse voltage reference required for the corresponding output pulse constant current control.

[0008] The common-phase amplifier circuit includes operational amplifiers N6-A and N6-B, wherein the common-phase input terminal of the operational amplifier N6-B serves as the input terminal of the common-phase amplifier circuit, and the inverting input terminal of N6-B is grounded via a resistor R21; the inverting input terminal of N6-B is connected to its output terminal via a resistor R18; a capacitor C6 is arranged in parallel at both ends of the resistor R18; the output terminal of the operational amplifier N6-B is connected to the common-phase input terminal of the operational amplifier N6-A, and the inverting input terminal of N6-A is connected to the output terminal; the output terminal of the operational amplifier N6-A is connected to the input terminal of the pulse current constant current drive signal forming circuit after being led out via a resistor R11.

[0009] The pulse current constant current driving signal forming circuit includes an operational amplifier N4, the in-phase input terminal of the operational amplifier N4 is connected to the output terminal of the pulse current reference forming circuit, and the in-phase input terminal of the operational amplifier N4 is also connected between the pulse current sampling resistor and the negative pole of the power supply through a resistor R9, so as to send the negative pulse voltage sampled by the sampling resistor to the in-phase input terminal of the operational amplifier N4; the inverting input terminal of the operational amplifier N4 is grounded through a resistor R13; the output terminal of the operational amplifier N4 is connected to the inverting input terminal of the operational amplifier N4 through a capacitor C4; the resistor R15 is connected in series with the capacitor C15 and then connected in parallel at both ends of C4; the output terminal lead-out terminal of the operational amplifier N4 is connected to the parallel follower driving and protection circuit as the output terminal of the pulse current constant current driving signal forming circuit.

[0010] The follower drive and protection circuit includes one or more parallel drive protection branches, each of which drives a pulse power constant current control switch; the drive protection branch includes a voltage follower, and the output end of the voltage follower is connected to the drive control end of the pulse power constant current control switch.

[0011] The voltage follower includes an operational amplifier N2, the in-phase input terminal of the operational amplifier N2 is connected to the output terminal of the pulse current constant current driving signal forming circuit, and the inverting input terminal is connected to the output terminal; the in-phase input terminal of the operational amplifier N2 is connected to the negative voltage clamping voltage through a diode V4; the output terminal of the operational amplifier N2 is connected to the control terminal of the pulse power constant current control switch through a resistor R6; wherein the output terminal of N2 is connected to the positive electrode of the diode V5, and the negative electrode of V5 is connected to between the resistor R6 and the control terminal of the pulse power constant current control switch through a resistor R3.

[0012] The driving protection branch also includes a resistor R4, a capacitor C1, and TVS tubes V1 and V3. The positive electrode of V1 is connected between the output end of the voltage follower and the control end of the pulse power constant current control switch, the negative electrode of V1 is connected to the negative electrode of V3, and the positive electrode of V3 is grounded; one end of the resistor R4 is connected to the positive electrode of V1, and the other end is connected to the positive electrode of V3, and the capacitor C1 is connected in parallel at both ends of the resistor R4.

[0013] The control circuit also includes a pulse current pulse width compensation circuit, whose output end is used to compensate and control the pulse width of the pulse current, and whose output end is connected to the input end of the pulse current constant current drive signal forming circuit.

[0014] The pulse current pulse width compensation circuit includes an optocoupler driver N3, and the pulse width compensation signal PLUS_AUX is connected to the input end of the optocoupler isolation driver N3 through R8, and its output end is connected to the resistor R12, the resistor R12 is connected to the positive electrode of the diode V8, and the negative electrode of V8 leads to the output pin connected to the input end of the pulse current constant current drive signal forming circuit; the lead terminal between the output end of N3 and the resistor R12 is grounded through the resistor R14; the positive electrode of the diode V8 is grounded through the capacitor C3.

[0015] The advantages of the present invention are: the control circuit is reliable and can control the generation of stable constant current pulses. The pulse constant current source generated by the circuit has the advantages of short pulse front time, no pulse front overshoot, stable pulse current, pulse width can be adjusted by digital means such as FPGA, and large pulse power. At the same time, the pulse constant current closed-loop adjustment is simple and reliable, and the protection circuit for the power switch IGBT (or MOS tube) is simple and complete. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following is a brief description of the contents expressed in the drawings of the present invention and the symbols in the drawings:

[0017] Figure 1 This is a circuit schematic diagram of the control circuit of the present invention;

[0018] Figure 2 This is the timing diagram of the pulse constant current control circuit. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention will be further explained in detail below by describing the optimal embodiment with reference to the accompanying drawings.

[0020] The present invention discloses a pulse constant current control circuit, which is simple and reliable. It uses a resistor to sample the pulse current. The sampling resistor is not connected to the driving circuit of the IGBT (or MOS tube), but is connected between the reference ground (GND) and the negative pole of the DC voltage to form a negative pulse voltage return proportional to the pulse current. In addition, a pulse current control pulse voltage reference is formed by combining a current adjustment reference (I_ADJ) based on the DC voltage with a pulse control signal (PLUS). The pulse voltage reference is added to the negative pulse voltage obtained by sampling the pulse current to generate an error signal. The error signal is used to form a pulse current drive signal through an error amplifier to drive the pulse current control IGBT (or MOS tube) to form a pulse constant current control. The specific scheme is as follows:

[0021] like Figure 1 As shown, a pulse constant current control circuit includes a pulse current sampling resistor, a pulse current reference forming circuit, a pulse current constant current driving signal forming circuit and a follow-up driving and protection circuit;

[0022] The pulse current sampling resistor is arranged between the ground terminal of the power constant current control switch and the negative electrode of the DC power supply to collect a negative pulse voltage proportional to the pulse current, and its output end is connected to the input end of the pulse current constant current driving signal forming circuit;

[0023] The pulse current reference forming circuit is used to generate a pulse current controlled pulse voltage reference, and its output end is connected to the input end of the pulse current constant current drive signal forming circuit. The pulse current constant current drive signal forming circuit is used to generate an error signal based on the addition of the pulse voltage reference and the negative pulse voltage obtained by pulse current sampling. Its output end is connected to the follow-up drive and protection circuit, and the follow-up drive and protection circuit is used to drive and control the power constant current control switch to achieve pulse constant current control.

[0024] In a preferred embodiment, the control circuit further comprises a pulse current pulse width compensation circuit, whose output end is used to perform compensation control on the pulse width of the pulse current, and whose output end is connected to the input end of the pulse current constant current drive signal forming circuit.

[0025] When controlling, the conduction state of the IGBT can be driven by adjusting the PLUS signal and the reference signal, thereby achieving the purpose of forming a pulse constant current circuit on the IGBT power supply conduction circuit, thereby achieving adjustable and controllable pulse constant current output. In terms of pulse width, the pulse width can be compensated and adjusted by the PLUS_AUX signal to avoid the inconsistency between the output current pulse width and the PLUS signal pulse width in a wide current range, thereby achieving not only stable control of the pulse current but also stable regulation of the pulse width. A preferred implementation circuit for each specific module is as follows:

[0026] The pulse current sampling resistor includes a resistor R20; the G pole of the power constant current control switch is connected to the output end of the follower drive and protection circuit; the C pole (D pole) is connected to the positive pole DC+ of the power supply through the load LD1; the E pole (S pole) is grounded; one end of the resistor R20 is connected between the S pole of the power constant current control switch and the ground; the other end lead-out terminal is connected to the input end of the current constant current drive signal forming circuit.

[0027] The pulse current reference forming circuit includes an optocoupler isolation driver N5, a MOS tube V9, a pulse control signal PLUS, a current adjustment reference I_ADJ, and a common-mode amplifier circuit. The pulse control signal PLUS is connected to the input end of the optocoupler isolation driver, the output end of the optocoupler isolation driver N5 is connected to the G pole of the MOS tube V9, the G pole of V9 is connected to the cathode of the diode V12 through the resistor R17, the anode of the diode V12 is connected to the S pole of V9, and the cathode of the diode V12 is connected to a -5V power supply; the D pole of V9 is connected to the common-mode input end of the common-mode amplifier circuit and the current adjustment reference I_ADJ is input to the common-mode input end of the common-mode amplifier circuit; the common-mode amplifier circuit performs common-mode amplification on the input signal to obtain the pulse voltage reference required for the corresponding output pulse constant current control.

[0028] The common-phase amplifier circuit includes operational amplifiers N6-A and N6-B, wherein the common-phase input terminal of the operational amplifier N6-B serves as the input terminal of the common-phase amplifier circuit, and the inverting input terminal of N6-B is grounded via a resistor R21; the inverting input terminal of N6-B is connected to its output terminal via a resistor R18; a capacitor C6 is arranged in parallel at both ends of the resistor R18; the output terminal of the operational amplifier N6-B is connected to the common-phase input terminal of the operational amplifier N6-A, and the inverting input terminal of N6-A is connected to the output terminal, and the output terminal of the operational amplifier N6-A is connected to the input terminal of the pulse current constant current drive signal forming circuit after being led out via a resistor R11.

[0029] The pulse current constant current driving signal forming circuit includes an operational amplifier N4, the in-phase input terminal of the operational amplifier N4 is connected to the output terminal of the pulse current reference forming circuit, and the in-phase input terminal of the operational amplifier N4 is also connected between the pulse current sampling resistor and the negative pole of the power supply through a resistor R9, and is used to send the negative pulse voltage sampled by the sampling resistor to the in-phase input terminal of the operational amplifier N4; the inverting input terminal of the operational amplifier N4 is grounded through a resistor R13; the output terminal of the operational amplifier N4 is connected to the inverting input terminal of the operational amplifier N4 through a capacitor C4; the resistor R15 and the capacitor C15 are connected in series and then connected in parallel at both ends of C4; the output terminal lead-out terminal of the operational amplifier N4 is connected to the parallel follower driving and protection circuit as the output terminal of the pulse current constant current driving signal forming circuit.

[0030] The follower drive and protection circuit includes one or more parallel drive protection branches, each of which drives a pulse power constant current control switch; the drive protection branch includes a voltage follower, and the output end of the voltage follower is connected to the drive control end of the pulse power constant current control switch. The number of parallel drive protection branches is related to the number of MOS tubes or IGBTs, and each branch is used to drive and control an IGBT. IGBTs can be connected in parallel to form a control module, and then connected in series with the load between the positive and negative poles of the DC power supply.

[0031] The voltage follower includes an operational amplifier N2, the in-phase input terminal of the operational amplifier N2 is connected to the output terminal of the pulse current constant current driving signal forming circuit, and the inverting input terminal is connected to the output terminal; the in-phase input terminal of the operational amplifier N2 is connected to the negative voltage clamping voltage through a diode V4; the output terminal of the operational amplifier N2 is connected to the control terminal of the pulse power constant current control switch through a resistor R6; wherein the output terminal of N2 is connected to the positive electrode of the diode V5, and the negative electrode of V5 is connected to the resistor R6 and the control terminal of the pulse power constant current control switch through a resistor R3. The driving protection branch also includes a resistor R4, a capacitor C1, and TVS tubes V1 and V3, wherein the positive electrode of V1 is connected between the output terminal of the voltage follower and the control terminal of the pulse power constant current control switch, the negative electrode of V1 is connected to the negative electrode of V3, and the positive electrode of V3 is grounded; one end of the resistor R4 is connected to the positive electrode of V1, and the other end is connected to the positive electrode of V3, and the capacitor C1 is connected in parallel to both ends of the resistor R4.

[0032] The pulse current pulse width compensation circuit includes an optocoupler driver N3, and the pulse width compensation signal PLUS_AUX is connected to the input end of the optocoupler isolation driver N3 through R8, and its output end is connected to the resistor R12, the resistor R12 is connected to the positive electrode of the diode V8, and the negative electrode of V8 leads to the output pin connected to the input end of the pulse current constant current drive signal forming circuit; the lead terminal between the output end of N3 and the resistor R12 is grounded through the resistor R14; the positive electrode of the diode V8 is grounded through the capacitor C3.

[0033] The working principle of this application circuit is described as follows:

[0034] The pulse constant current control circuit mainly consists of a pulse current sampling resistor, a pulse current reference forming circuit based on a DC voltage and a pulse control signal, a pulse current pulse width compensation circuit, a pulse current constant current drive signal forming circuit, and a parallel follower drive and protection circuit, which can drive two or more parallel IGBT (or MOS tube) circuits. The pulse constant current source generated by the circuit of the present invention has the advantages of short pulse front edge time, no overshoot of the pulse front edge, stable pulse current, pulse width can be adjusted by digital means such as FPGA, and large pulse power. At the same time, the pulse constant current closed-loop adjustment is simple and reliable, and the protection circuit for the power switch IGBT (or MOS tube) is popular and complete.

[0035] like Figure 1 As shown, the pulse constant current control circuit circuit diagram of the present invention, Figure 2As shown, the timing diagram of the pulse constant current control circuit of the present invention. The pulse current regulation voltage reference I_ADJ is connected to the 5th pin of the operational amplifier N6-B through R19, the pulse current frequency and duty cycle control signal PLUS is connected to the 1st pin of the optocoupler isolation driver N5 through R10, the 3rd pin of N5 is connected to the isolation ground DGND, the 6th pin of N5 is connected to the +5V power supply, the 4th pin of N5 is connected to the -5V power supply, and the 5th pin of N5 outputs the pulse control signal, that is, the 5th pin of N5 is connected to the MOS through R16. The G pole (V9-1) of the tube V9 is pulled down to -5V through the resistor R17, the S pole (V9-2) of V9 is connected to the positive pole of the diode V12, the negative pole of the diode V12 is connected to the -5V power supply, the D pole (V9-3) of V9 is connected to the 5th pin of the operational amplifier N6-B, the 6th pin of N6-B is connected to GND through the resistor R21, and the 6th pin of N6-B is connected to the 7th pin of N6-B through the resistor R18. After the I_ADJ and PLUS are integrated and then amplified in the same phase, the pulse voltage standard required for the corresponding output pulse constant current control is obtained. A capacitor C6 is connected in parallel to the resistor R16, and the operational amplifier N6-B The pulse voltage quasi-base outputted from the 7th foot is connected to the voltage follower, i.e., the 3rd foot of the operational amplifier N6-A. The 2nd foot of N6-A is short-circuited with the 1st foot of N6-A. The 1st foot of N6-A is connected to the 3rd foot of the operational amplifier N4 through the resistor R11. The pulse voltage quasi-base is added with the negative pulse voltage obtained by sampling the current of the current loop composed of DC+ (positive pole of DC voltage), LD1 (load), constant current control switch IGBT, i.e., V10 and V11, R20 (current sampling resistor), and DC- (negative pole of DC voltage) through the current sampling resistor R20 to obtain the corresponding pulse current error pulse voltage. The 3rd foot and the 2nd foot of the current sampling resistor R20 are connected to the 3rd foot of the operational amplifier N4 through the resistor R9. The error pulse voltage passes through the error amplifier composed of the operational amplifier N4 to obtain the error amplified pulse voltage (the 2nd foot of the operational amplifier N4 is connected to GND through the resistor R13. In addition, the 2nd foot of the operational amplifier N4 is connected to GND through the capacitor C4 Connected to the 6th pin of N4, and the 2nd pin of N4 is connected to the 1st pin of resistor R15, and the 2nd pin of R15 is connected to the 6th pin of N4 through capacitor C5). The error amplified pulse voltage is connected to two voltage followers through the 6th pin of op amp N4 through resistor R7, namely, the 3rd pin of op amp N2 and the 3rd pin of op amp N1. The 6th pin output of N2 is connected to the G pole (V10-3) of IGBT through resistor R6. At the same time, the 6th pin output of N2 is connected to the positive pole of diode V5, and the negative pole of diode V5 is also connected to V10-3 through resistor R3 to drive IGBT (V10) to obtain the required pulse constant current source.The output of the 6th pin of N1 is connected to the G pole (V11-3) of the IGBT through the resistor R2. At the same time, the output of the 6th pin of N1 is connected to the positive pole of the diode V2. The negative pole of the diode V2 is also connected to V11-3 through the resistor R1 to drive the IGBT (V11), which plays the role of parallel current expansion of two IGBTs. In the circuit, the 2nd pin of N2 is short-circuited with the 6th pin of N2, the 2nd pin of N1 is short-circuited with the 6th pin of N1, the 2nd pin of the resistor R7 is connected to the negative pole of the diode V4, and the positive pole of the diode V4 is connected to the -9V voltage to clamp the negative voltage of the error amplification pulse voltage to -9V, meeting the negative turn-off voltage requirement of the IGBT / MOS tube. Among them, the third pin of V10 is connected to GND through resistor R4 and capacitor C1, and the third pin of V10 is connected to the positive electrode of TVS tube V1, the negative electrode of V1 is connected to the negative electrode of TVS tube V3, and the positive electrode of V3 is connected to GND. The third pin of V11 is connected to GND through resistor R5 and capacitor C2, and the third pin of V11 is connected to the positive electrode of TVS tube V6, the negative electrode of V6 is connected to the negative electrode of TVS tube V7, and the positive electrode of V7 is connected to GND. In addition, the fifth pin of V10 and the fifth pin of V11 are both connected to GND to form corresponding protection for IGBT / MOS tube. Among them, the DC power supply DC+ is connected to the positive electrode of LD1, the negative electrode of LD1 is connected to the first pin of V10 and the first pin of V11, the second pin of V10 and the second pin of V11 are connected to GND, the DC power supply DC- is connected to the third pin and the second pin of the current sampling resistor R20, and the fourth pin and the first pin of the current sampling resistor R20 are connected to GND to form a pulse constant current main loop.

[0036] The pulse width compensation signal PLUS_AUX is connected to the first pin of the optocoupler isolation driver N3 through R8, the third pin of N3 is connected to the isolation ground DGND, the sixth pin of N3 is connected to the +12V power supply, the fourth pin of N3 is connected to GND, and the fifth pin of N3 is connected to GND through the resistor R14. Then the pulse width compensation voltage output by N3, that is, the fifth pin of N3 is connected to one end of the capacitor C3 through R12, and the other end of C3 is connected to GND. The common connection end of R12 and C3 is connected to the positive pole of the diode V8, and the negative pole of the diode V8 is connected to the third pin of the operational amplifier N4 to speed up the rising speed of the pulse constant current front edge, so as to avoid the phenomenon that the output current pulse width becomes narrower due to the setting pulse current becoming smaller, and finally form the PLUS_I_OUT pulse constant current on the load LD1. In summary, the purpose of pulse constant current control is achieved.

[0037] Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, they are all within the protection scope of the present invention.

Claims

1. A pulse constant current control circuit, characterized in that: It includes a pulse current sampling resistor, a pulse current reference forming circuit, a pulse current constant current drive signal forming circuit and a follow-up drive and protection circuit. The pulse current sampling resistor is arranged between the ground terminal of the power constant current control switch and the negative pole of the DC power supply to collect a negative pulse voltage proportional to the pulse current, and its output end is connected to the input end of the pulse current constant current drive signal forming circuit; the pulse current reference forming circuit is used to generate a pulse current control pulse voltage reference, and its output end is connected to the input end of the pulse current constant current drive signal forming circuit. The pulse current constant current drive signal forming circuit is used to generate an error signal according to the pulse voltage reference and the negative pulse voltage obtained by pulse current sampling. Its output end is connected to the follow-up drive and protection circuit. The follow-up drive and protection circuit is used to drive and control the power constant current control switch to achieve pulse constant current control.

2. A pulse constant current control circuit as claimed in claim 1, characterized in that: The pulse current sampling resistor includes a resistor R20; the G pole of the power constant current control switch is connected to the output end of the follower drive and protection circuit; the C pole is connected to the positive pole DC+ of the power supply through the load LD1; the E pole is grounded; one end of the resistor R20 is connected between the E pole of the power constant current control switch and the ground; the other end leads to a terminal connected to the input end of the current constant current drive signal forming circuit.

3. A pulse constant current control circuit as claimed in claim 1, characterized in that: The pulse current reference forming circuit includes an optocoupler isolation driver N5, a MOS tube V9, a pulse control signal PLUS, a current adjustment reference I_ADJ, and a common-mode amplifier circuit. The pulse control signal PLUS is connected to the input end of the optocoupler isolation driver, and the output end of the optocoupler isolation driver N5 is connected to the G pole of the MOS tube V9. The G pole of V9 is connected to the cathode of the diode V12 through a resistor R17, the anode of the diode V12 is connected to the S pole of V9, and the cathode of the diode V12 is connected to a -5V power supply; the D pole of V9 is connected to the common-mode input end of the common-mode amplifier circuit, and the current adjustment reference I_ADJ is input to the common-mode input end of the common-mode amplifier circuit; the common-mode amplifier circuit performs common-mode amplification on the input signal to obtain the pulse voltage reference required for the corresponding output pulse constant current control.

4. A pulse constant current control circuit as claimed in claim 3, characterized in that: The common-phase amplifier circuit includes operational amplifiers N6-A and N6-B, wherein the common-phase input terminal of the operational amplifier N6-B serves as the input terminal of the common-phase amplifier circuit, and the inverting input terminal of N6-B is grounded via a resistor R21; the inverting input terminal of N6-B is connected to its output terminal via a resistor R18; a capacitor C6 is arranged in parallel at both ends of the resistor R18; the output terminal of the operational amplifier N6-B is connected to the common-phase input terminal of the operational amplifier N6-A, and the inverting input terminal of N6-A is connected to the output terminal; the output terminal of the operational amplifier N6-A is connected to the input terminal of the pulse current constant current drive signal forming circuit after being led out via a resistor R11.

5. A pulse constant current control circuit as claimed in claim 1, characterized in that: The pulse current constant current driving signal forming circuit includes an operational amplifier N4, the in-phase input terminal of the operational amplifier N4 is connected to the output terminal of the pulse current reference forming circuit, and the in-phase input terminal of the operational amplifier N4 is also connected between the pulse current sampling resistor and the negative pole of the power supply through a resistor R9, so as to send the negative pulse voltage sampled by the sampling resistor to the in-phase input terminal of the operational amplifier N4; the inverting input terminal of the operational amplifier N4 is grounded through a resistor R13; the output terminal of the operational amplifier N4 is connected to the inverting input terminal of the operational amplifier N4 through a capacitor C4; the resistor R15 is connected in series with the capacitor C15 and then connected in parallel at both ends of C4; the output terminal lead-out terminal of the operational amplifier N4 is connected to the parallel follower driving and protection circuit as the output terminal of the pulse current constant current driving signal forming circuit.

6. A pulse constant current control circuit as claimed in claim 1, characterized in that: The follower drive and protection circuit includes one or more parallel drive protection branches, each of which drives a pulse power constant current control switch; the drive protection branch includes a voltage follower, and the output end of the voltage follower is connected to the drive control end of the pulse power constant current control switch.

7. A pulse constant current control circuit as claimed in claim 6, characterized in that: The voltage follower includes an operational amplifier N2, the in-phase input terminal of the operational amplifier N2 is connected to the output terminal of the pulse current constant current driving signal forming circuit, and the inverting input terminal is connected to the output terminal; the in-phase input terminal of the operational amplifier N2 is connected to the negative voltage clamping voltage through a diode V4; the output terminal of the operational amplifier N2 is connected to the control terminal of the pulse power constant current control switch through a resistor R6; wherein the output terminal of N2 is connected to the positive electrode of the diode V5, and the negative electrode of V5 is connected to between the resistor R6 and the control terminal of the pulse power constant current control switch through a resistor R3.

8. A pulse constant current control circuit as claimed in claim 7, characterized in that: The driving protection branch also includes a resistor R4, a capacitor C1, and TVS tubes V1 and V3. The positive electrode of V1 is connected between the output end of the voltage follower and the control end of the pulse power constant current control switch, the negative electrode of V1 is connected to the negative electrode of V3, and the positive electrode of V3 is grounded; one end of the resistor R4 is connected to the positive electrode of V1, and the other end is connected to the positive electrode of V3, and the capacitor C1 is connected in parallel at both ends of the resistor R4.

9. A pulse constant current control circuit according to any one of claims 1 to 8, characterized in that: The control circuit also includes a pulse current pulse width compensation circuit, whose output end is used to compensate and control the pulse width of the pulse current, and whose output end is connected to the input end of the pulse current constant current drive signal forming circuit.

10. A pulse constant current control circuit as claimed in claim 9, characterized in that: The pulse current pulse width compensation circuit includes an optocoupler driver N3, and the pulse width compensation signal PLUS_AUX is connected to the input end of the optocoupler isolation driver N3 through R8, and its output end is connected to the resistor R12, the resistor R12 is connected to the positive electrode of the diode V8, and the negative electrode of V8 leads to the output pin connected to the input end of the pulse current constant current drive signal forming circuit; the lead terminal between the output end of N3 and the resistor R12 is grounded through the resistor R14; the positive electrode of the diode V8 is grounded through the capacitor C3.

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