CN216526848U

CN216526848U - Multi-channel wide-range adjustment linear constant current driving circuit with CAN communication

Info

Publication number: CN216526848U
Application number: CN202220170321.6U
Authority: CN
Inventors: 邬李红; 龙勇; 王川东
Original assignee: Chengdu Zhanwei Electromechanical Automation Co ltd
Current assignee: Chengdu Zhanwei Electromechanical Automation Co ltd
Priority date: 2022-01-21
Filing date: 2022-01-21
Publication date: 2022-05-13
Anticipated expiration: 2032-01-21

Abstract

The utility model provides a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication, which comprises a control circuit, wherein the control circuit adopts an SWM320VET7 singlechip as a main control chip, and is characterized in that the control circuit is respectively connected with a USB communication circuit, a CAN bus communication circuit and a DAC (digital-to-analog converter) conversion circuit, and the DAC conversion circuit is respectively connected with a plurality of PID (proportion integration differentiation) adjustment constant current source circuits.

Description

Multi-channel wide-range adjustment linear constant current driving circuit with CAN communication

Technical Field

The utility model relates to the field of multichannel independent linear constant current, in particular to a multichannel wide-range adjustment linear constant current driving circuit with CAN communication.

Background

At present, in the fields of sensor calibration, optical instrument detection and calibration and the like, old light sources are mostly adopted as standard light sources, and optical sensors can select several light sources to assist in the calibration process to complete the whole process, for example, incandescent lamps, halogen lamps, LEDs and the like are used as standard lamps, an alternating current voltage regulating power supply is adopted to regulate the brightness, and an external program control switch overweight sunshade mechanism is used for on and off of an open lamp source.

Disclosure of Invention

Aiming at the problems, the utility model provides a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication.

The utility model is realized by the following technical scheme:

the utility model has the beneficial effects that:

the utility model provides a take multichannel wide region of CAN communication to adjust linear constant current drive circuit, includes control circuit, control circuit includes main control chip, control circuit connects USB communication circuit, CAN bus communication circuit and DAC converting circuit respectively, DAC converting circuit connects PID regulation constant current source circuit, DAC converting circuit and PID regulation constant current source circuit constitute the constant current source branch road, the constant current source branch road has 9 ways.

Further, the USB communication circuit includes a USB-B interface J4, a pin 1 of the USB-B interface J4 is connected to a pin 3 of an LR2010B-T50 voltage regulation chip U5, a pin 2 of the LR2010B-T50 voltage regulation chip U50 is connected to a pin 4 of a 50 UCR esd protection diode U50, one end of a capacitor C50, and one end of a bead inductor FB 50, a pin 2 of the 50 UCR esd protection diode U50 is connected to a pin 4 of a resistor R50, one end of a capacitor C50, and a pin 9 of a FT230 50 conversion chip U50, a pin 3 of the 50 UCR esd protection diode U50 is connected to a pin 3 of a resistor R50, one end of a capacitor C50, one end of a pin 8 of the FT230 conversion chip U50, a pin 3 of the resistor R50 is connected to a pin 3 of the USB-B interface J50, a pin 2 of the USB-B interface J50 is connected to the other end of the bead 50, and one end of the capacitor C50 are connected to a pin 50, respectively, The FT230XS converts the 12 pins of the chip U7, the 10 pins and the 11 pins of the FT230XS conversion chip U7 are respectively connected with one end of a capacitor C16, the 3 pins of the FT230XS conversion chip U7, one end of a resistor R10 and one end of a resistor R11, the other end of the resistor R10 is connected with the anode of the light-emitting diode LD2, the other end of the resistor R11 is connected with the anode of the light-emitting diode LD3, the cathode of the light emitting diode LD2 is connected with the 14 pins of the FT230XS conversion chip U7, the cathode of the light emitting diode LD3 is connected with the 7 pins of the FT230XS conversion chip U7, the 4 pin and the 5 pin of the USB-B interface, the 1 pin of an LR2010B-T50 voltage stabilizing chip U5, the 1 pin of a JEU05UCR electrostatic protection diode U6, the other end of a capacitor C11, the other end of a capacitor C12, the other end of a capacitor C13, the other end of a capacitor C14, the other end of a capacitor C15, the other end of a capacitor C16, and the 5 pin and the 13 pin of an FT230XS conversion chip U7 are all connected with the end voltage of the ground terminal.

Further, a pin 1 of the FT230XS conversion chip U7 is connected to a pin 3 of a TLP2362 photocoupler U9, a pin 1 of the TLP2362 photocoupler U9 is connected to one end of a resistor R13, a pin 6 is connected to a 3.3V voltage output end, a pin 5 is respectively connected to one end of a resistor R15 and RXD of the SWM320VET7 chip, the pin 4 is grounded, the other end of the resistor R13 is connected to a driving voltage, and a voltage output end of a power supply circuit at the other end of the resistor R15 is connected to a voltage output end.

Further, the 4 pins of the FT230XS conversion chip U7 are connected to the 5 pin of a TLP2362 photocoupler U8 and one end of a resistor R14 respectively, the 6 pin of the TLP2362 photocoupler U8 is connected to a driving voltage, the 1 pin is connected to one end of a resistor R12, the 3 pin is connected to the TXD of the SWM320VET7 chip, the 4 pin is connected to a ground terminal voltage, the other end of the resistor R14 is connected to the driving voltage, and the other end of the resistor R12 is connected to a voltage output end of the power supply circuit.

Furthermore, the CAN communication bus circuit comprises a MAX3051CAN transceiving chip U4, wherein

pins

1, 4 and 5 of the MAX3051CAN transceiving chip U4 are all connected with the control circuit,

pins

8 and 2 are all grounded, pin 3 is connected with the output end of power supply voltage, pin 6 is connected with a CAN low-speed bus, pin 7 is connected with a CAN high-speed bus, and a resistor R7 is connected between the CAN low-speed bus and the CAN high-speed bus in parallel.

Furthermore, the number of the DAC conversion circuits is matched with that of the PID adjusting constant current source circuits, each DAC conversion circuit comprises a second-order RC circuit, one end of each second-order RC circuit is connected with the PWM output end of the SWM320VET7 chip, the other end of each second-order RC circuit is connected with the positive phase input end of the RS8557 operational amplifier U10, and the negative phase input end and the output end of the RS8557 operational amplifier U10 are respectively connected with one end of the resistor R17 and the direct current signal output end.

Furthermore, an 8 pin of the RS8557 operational amplifier is connected with an output end of a power voltage, a 2 pin of the RS8557 operational amplifier is grounded, and the other end of the resistor R17 is grounded.

Further, there are 9 PID adjusting constant current source circuits, each PID adjusting constant current source circuit includes a resistor R18, one end of the resistor R18 is connected to the dc signal output end, the other end of the resistor R18 is connected to the non-inverting input end of the operational amplifier U11B, the inverting input end of the operational amplifier is connected to one end of the resistor R19, one end of the capacitor C10, the other end of the capacitor C10 is connected to the output end of the operational amplifier U11B, one end of the resistor R29, and one end of the resistor R30, the other end of the resistor R29 is connected to the base of the NPN triode Q1, the other end of the resistor R30 is connected to the base of the NPN triode Q2, the collector of the NPN triode Q1 is connected to the 9V voltage output end, the emitter of the NPN triode Q1 is connected to the emitter and the negative output end of the NPN triode Q2, the collector of the NPN triode Q2 is connected to the 9V voltage output end, and the other end of the resistor R19 is connected to the output end of the operational amplifier U11A, the other end of the resistor R20, the other end of the resistor R20 is connected to the inverting input terminal of the operational amplifier U11A and the one end of the resistor R21, the non-inverting input terminal of the operational amplifier U11A is connected to the one end of the resistor R22 and the one end of the resistor R23, the other end of the resistor R21 is connected to the one end of the resistor R24 and the source of the NMOS transistor Q3, the other end of the resistor R23 is connected to the other end of the resistor R24 and the one end of the resistor R25, the other end of the resistor R25 is connected to the positive output terminal, the drain of the NMOS transistor Q3 is connected to the one end of the resistor R26, the other end of the resistor R26 is grounded, the gate of the NMOS transistor Q3 is connected to the one end of the resistor R27, the other end of the resistor R27 is connected to the one end of the resistor R28 and the control output terminal, and the other end of the resistor R28 is grounded.

The utility model has the beneficial effects that:

the multi-channel wide-range adjustment linear constant current driving circuit with CAN communication comprises 9 groups of independent constant currents, each constant current part adopts a linear constant current mode, hardware PID adjustment is achieved, intensity and frequency CAN be adjusted through commands, the intensity adjustment range is 0-65535, the frequency range is 0-1KHZ, the problem of few channels is solved, the simultaneous adjustment of intensity and frequency is achieved, in addition, a CAN bus interface is added, the multi-channel wide-range adjustment linear constant current driving circuit CAN be used for controlling an execution mechanism or a sensor to sample, and the expansion of more control functions is facilitated.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a block diagram of a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention;

FIG. 2 is a schematic diagram of a CAN bus communication circuit of a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention;

FIG. 3 is a schematic diagram of a USB communication circuit of a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention;

FIG. 4 is a schematic diagram of a PID adjustment constant current source circuit of a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention;

FIG. 5 is a schematic diagram of a DAC conversion circuit of the multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention;

fig. 6 is a circuit diagram of a main control chip of the multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.

Example 1

Referring to fig. 1, a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication comprises a control circuit, wherein the control circuit adopts an SWM320VET7 single chip microcomputer as a main control chip, and is characterized in that the control circuit is respectively connected with a USB communication circuit, a CAN bus communication circuit and a DAC conversion circuit, the DAC conversion circuit is respectively connected with a plurality of PID adjustment constant current source circuits, wherein the control circuit, the USB communication circuit, the CAN bus communication circuit, 9 DAC conversion circuits and 9 PID adjustment constant current source circuits are respectively connected with a power supply circuit, the SWM320VET7 single chip microcomputer comprises a plurality of pins with different functions and circuits for connecting different functions, wherein the USB communication circuit is used for converting a USB signal into a TTL serial signal and connecting the TTL serial signal to the SWM320VET7 single chip microcomputer, the CAN bus communication circuit is used for converting a differential signal into a TTL signal and transmitting the TTL signal to the SWM320VET7, and the DAC conversion circuit is used for converting a PWM signal output by the SWM320VET7 into a direct current single chip microcomputer, the PID adjusting constant current source circuit is used for dynamic adjustment of a constant current source, dynamic balance is realized, dynamic adjustment of a light source is facilitated, and the power supply circuit can provide 9V power supply voltage, 5V power supply voltage, 3.3V power supply voltage and 1.8V power supply voltage.

Example 2

Referring to fig. 2 to 6, this embodiment provides a specific circuit principle of a multi-channel wide-range adjustment linear constant current driving circuit with CAN communication based on embodiment 1.

Further, the USB communication circuit includes a USB-B interface J4, a pin 1 of the USB-B interface J4 is connected to a pin 3 of a LR2010B-T50 zener chip U5, the zener chip U5 is configured to output high-precision voltage and current, reduce power consumption and provide protection for current output, a pin 2 of the LR2010B-T50 zener chip U5 is connected to a pin 4 of a JEU05UCR ESD diode U6, one end of a capacitor C13 and one end of a bead inductor FB1, the ESD diode U6 is an ESD diode, and is connected in parallel to the USB communication circuit, when the circuit normally operates, the ESD diode is in a cut-off state, and does not affect normal operation of the circuit, when the circuit generates abnormal overvoltage and reaches its breakdown voltage, the ESD diode rapidly changes from a high-resistance state to a low-resistance state, and provides a low-impedance conduction path for instantaneous current, and clamps the abnormal high voltage within a safe level, thereby protecting the protected circuit; when abnormal overvoltage disappears, the circuit recovers to a high resistance state, the circuit works normally and is used for electrostatic protection of a USB interface, a pin 2 of the JEU UCR electrostatic protection diode U6 is respectively connected with one end of a resistor R9, one end of a capacitor C12 and a pin 9 of the FT230XS conversion chip U7, a pin 3 of the JEU UCR electrostatic protection diode U6 is respectively connected with one end of a resistor R8, one end of a capacitor C11 and an 8 pin of the FT230XS conversion chip U7, the other end of the resistor R8 is connected with a pin 3 of the USB-B interface J8, the other end of the resistor R8 is connected with a pin 2 of the USB-B interface J8, the other end of the magnetic bead inductor FB 8 is respectively connected with one end of a capacitor C8, one end of a capacitor C8 and a pin 12 of the FT230 conversion chip U8, a pin 10 and a pin 11 of the FT 8 conversion chip U8 are respectively connected with one end of the capacitor C8, a pin 3 of the FT 8 and a pin 3 of the conversion chip U8, a terminal R8 and a terminal of the USB chip 8, and a conversion protocol conversion chip U8, the USB-to-asynchronous serial data transmission interface is provided, a 3.3V voltage power supply is needed, the other end of the resistor R10 is connected with the anode of the light emitting diode LD2, the other end of the resistor R11 is connected with the anode of the light emitting diode LD3, the cathode of the light emitting diode LD2 is connected with the 14 pin of the FT230XS conversion chip U7, the cathode of the light emitting diode LD3 is connected with the 7 pin of the FT230XS conversion chip U7, the 4 pin and the 5 pin of the USB-B interface, the 1 pin of the LR2010B-T50 voltage stabilization chip U5, the 1 pin of the JEU05UCR electrostatic protection diode U6, the other end of the capacitor C11, the other end of the capacitor C12, the other end of the capacitor C13, the other end of the capacitor C14, the other end of the capacitor C15, the other end of the capacitor C16, the 5 pin and the 13 pin of the FT230XS conversion chip U7 are all connected with the grounding terminal voltage.

Further, a pin 1 of the FT230XS conversion chip U7 is connected to a pin 3 of a TLP2362 photocoupler U9, a pin 1 of the TLP2362 photocoupler U9 is connected to one end of a resistor R13, a pin 6 is connected to a 3.3V voltage output end, a pin 5 is respectively connected to one end of a resistor R15 and an RXD of the SWM320VET7 chip, the pin 4 is grounded, the other end of the resistor R13 is connected to a driving voltage, and the other end of the resistor R15 is connected to a 3.3V voltage output end.

Further, the 4 pins of the FT230XS conversion chip U7 are connected to the 5 pin of a TLP2362 photocoupler U8 and one end of a resistor R14 respectively, the 6 pin of the TLP2362 photocoupler U8 is connected to a driving voltage, the 1 pin is connected to one end of a resistor R12, the 3 pin is connected to the TXD of the SWM320VET7 chip, the 4 pin is connected to a ground terminal voltage, the other end of the resistor R14 is connected to the driving voltage, and the other end of the resistor R12 is connected to a 3.3V voltage output terminal, wherein the photocouplers U8 and U9 are open collector output type inverter logic couplers, and are suitable for insulating RS-422, RS-485 and other transmission signals, and enhance the ability of transmitting TTL serial signals.

Further, the CAN communication bus circuit comprises a MAX3051CAN transceiving chip U4,

pins

8 and 2 are all grounded, pin 3 is connected with a 3.3V voltage output end, pin 6 is connected with a CAN low-speed bus, pin 7 is connected with a CAN high-speed bus, and a resistor R7 is connected in parallel between the CAN low-speed bus and the CAN high-speed bus, wherein the transceiving chip U4 provides differential transmission capability for the physical bus, provides differential receiving capability for the CAN controller, is suitable for 3.3V power supply voltage, TXD of the transceiving chip U4 is connected with a TXD pin of the SWM320VET7 single chip, RXD is connected with an RXD pin of the SWM320VET7 single chip, and SHDN is connected with a SHDN pin of the SWM320VET7 single chip.

Furthermore, the number of the DAC conversion circuits is matched with the number of the PID adjusting constant current source circuits, each DAC conversion circuit comprises a second-order RC circuit, one end of each second-order RC circuit is connected with the PWM output end of the SWM320VET7 chip, the other end of each second-order RC circuit is connected with the non-inverting input end of the RS8557 operational amplifier U10, the inverting input end and the output end of the RS8557 operational amplifier U10 are respectively connected with one end of a resistor R17 and a direct current signal output end, the second-order RC circuit comprises a resistor R15 and a resistor R16 which are connected in series, a capacitor C17 which is connected between a resistor R15 and a resistor R16 in parallel, a capacitor C18 connected in parallel between the resistor R16 and the operational amplifier U10, the other end of the resistor R15 is connected with a PWM model output pin of the singlechip, when the conversion sub-circuit receives the PWM square waveform output by the single chip microcomputer, the PWM square waveform is shaped into a direct current signal through the second-order RC circuit, and the direct current signal is amplified by the operational amplifier U10 in an enhanced mode and then is stably output.

Furthermore, the output current is controlled in a closed loop manner by adopting a hardware PID mode, the number of the PID adjusting constant current source circuits is 9, each PID adjusting constant current source circuit comprises a resistor R18, one end of the resistor R18 is connected with a direct current signal output end, the other end of the resistor R18 is connected with a non-inverting input end of an operational amplifier U11B, inverting input ends of the operational amplifiers are respectively connected with one end of a resistor R19, one end of a capacitor C10, the other end of the capacitor C10 is respectively connected with an output end of the operational amplifier U11B, one end of a resistor R29 and one end of a resistor R30, the other end of the resistor R29 is connected with a base electrode of an NPN triode Q1, the other end of the resistor R30 is connected with a base electrode of an NPN triode Q2, a collector electrode of the NPN triode Q1 is connected with a 9V voltage output end, emitter electrodes of the NPN triode Q1 are respectively connected with an emitter electrode and a negative electrode of an NPN triode Q2, a collector electrode of the NPN triode Q2 is connected with a 9V voltage output end, the other end of the resistor R19 is connected with the output end of an operational amplifier U11A, one end of a resistor R20 is connected, the other end of the resistor R20 is connected with the inverting input end of an operational amplifier U11A, one end of a resistor R21, the non-inverting input end of the operational amplifier U11A is connected with one end of a resistor R22 and one end of a resistor R23, the other end of the resistor R22 is grounded, the other end of the resistor R21 is connected with one end of a resistor R24 and the source electrode of an NMOS tube Q3, the other end of the resistor R23 is connected with the other end of a resistor R24, one end of a resistor R25, the other end of the resistor R25 is connected with the anode output end, the drain electrode of the NMOS tube Q3 is connected with one end of a resistor R26, the other end of the resistor R26 is grounded, the gate of the NMOS tube Q3 is connected with one end of a resistor R27, the other end of the resistor R27 is connected with one end of a resistor R28 and the control output end, the other end of the resistor R28 is grounded, the PID adjusting constant current source circuit receives 1 control signal, for example, after receiving a PWM square wave signal sent by an EN _ IR800_ PWM pin of an SWM320VET7 single chip microcomputer EN _ IR800_ PWM, the PID adjusting constant current source circuit forms an IR800_ DAC direct current control signal through a conversion sub-circuit for converting the EN _ IR800_ PWM square wave signal in the DAC conversion circuit, the PID adjusting constant current source circuit samples the signal through a resistor R24 until a current set value is reached, and finally dynamically adjusts the light source of the light source board through the current provided by the PID adjusting constant current source circuit.

Example 3

In this embodiment, an explanation of the output of 9 PID adjusting constant current source circuits of a multi-channel wide-range adjusting linear constant current driving circuit with CAN communication is provided on the basis of embodiment 1.

The first PID adjusting constant current source circuit comprises a positive output end with an interface number of IR950, a negative output end of IR950 and a signal input end of IR950 DAC; the second PID adjusting constant current source circuit comprises an IR880 positive electrode output end, an IR880 negative electrode output end and an IR880DAC signal input end, wherein the interface number of the IR880 positive electrode output end is the number of the interface; the third PID adjusting constant current source circuit comprises an anode output end with an interface number of IR850, an IR850 cathode output end and an IR850DAC signal input end; the fourth PID adjusting constant current source circuit comprises an IR800 positive electrode output end, an IR800 negative electrode output end and an IR800DAC signal input end, wherein the interface number of the positive electrode output end is IR 800; the fifth PID adjusting constant current source circuit comprises an IR760 interface positive output end, an IR760 interface negative output end and an IR760DAC signal input end; the sixth PID adjusting constant current source circuit comprises an IR720 positive output end, an IR720 negative output end and an IR720DAC signal input end, wherein the interface number of the IR720 positive output end and the interface number of the IR720 negative output end are the same as the interface number of the IR720DAC signal input end; the seventh PID adjusting constant current source circuit comprises a positive electrode output end with an interface number of IR680, a negative electrode output end of the IR680 and a signal input end of an IR680 DAC; the eighth PID adjusting constant current source circuit comprises a positive output end with the interface number being WhiteC, a WhiteC negative output end and a WhiteC signal input end; the ninth PID adjusting constant current source circuit comprises a positive output end with the interface number being WhiteW, a WhiteW negative output end and a WhiteW signal input end. Correspondingly, each conversion sub-circuit is provided with a corresponding input end for receiving the PWM square wave signal, and each corresponding input end is respectively connected with a corresponding pin of the SWM320VET7 singlechip.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof.

It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the utility model as claimed. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides a take multichannel wide region of CAN communication to adjust linear constant current drive circuit, includes control circuit, control circuit includes main control chip, its characterized in that, control circuit connects USB communication circuit, CAN bus communication circuit and DAC converting circuit respectively, DAC converting circuit connects PID and adjusts constant current source circuit, DAC converting circuit and PID adjust constant current source circuit constitute the constant current source branch road, the constant current source branch road has 9 ways.

2. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 1, wherein the USB communication circuit includes a USB-B interface J4, a pin 1 of the USB-B interface J4 is connected to a pin 3 of a LR2010B-T50 regulated chip U5, a pin 2 of the LR2010B-T50 regulated chip U5 is connected to a pin 4 of a JEU UCR esd diode U6, a pin one of a capacitor C13, and a pin one of a bead inductor FB1, a pin 2 of the JEU UCR esd diode U6 is connected to a pin 2 of a resistor R9, a pin of a capacitor C12, and a pin 9 of a FT230 12 conversion chip U12, a pin 3 of the 12 UCR esd diode U12 is connected to a pin one of a resistor R12, a pin one of a capacitor C12 and a pin 12 of the FT230 conversion chip U12, the other end of the resistor R12 is connected to a pin 3 of the USB-B interface J12, and a pin 2 of the USB-B12 interface J12, the other end of the magnetic bead inductor FB1 is connected with one end of a capacitor C1, one end of a capacitor C1 and a 12 pin of an FT230 1 conversion chip U1, the pin 10 and the pin 11 of the FT230 1 conversion chip U1 are connected with one end of a capacitor C1, the pin 3 of the FT230 1 conversion chip U1, one end of a resistor R1 and one end of a resistor R1, the other end of the resistor R1 is connected with the anode of a light emitting diode LD 1, the cathode of the light emitting diode LD 1 is connected with the pin 14 of the FT230 1 conversion chip U1, the cathode of the light emitting diode LD 1 is connected with the pin 7 of the FT230 1 conversion chip U1, the pin 4, the pin 5 of the USB-B interface, the pin 1 pin of the LR 2010-T1 voltage stabilization chip U1, the pin 1 pin of the UCR 1 electrostatic protection diode U1, the other end of the capacitor C1 and the other end of the capacitor C1, the other end of the resistor 1 and the resistor 1 of the resistor 1, the negative terminal of the LED 1 of the negative electrode of the LED 1 conversion chip LD 1 conversion chip U1, the negative terminal of the resistor R1, the negative terminal of the LED 1, the resistor R1, the negative terminal of the resistor R1, and the negative terminal of the chip U1 of the resistor and the resistor 1 of the resistor R1 of the chip U1 of the resistor 1 of the negative terminal of the chip U1 of the resistor R1 of the resistor 1 of the chip U1 of the resistor and the resistor D1 of the resistor R1 of the resistor D1 of the resistor 1 of the current-T1, and the current-T1 of the chip U1 of the current transformer, and the resistor D1 of the negative of the chip U1 of the negative terminal of the resistor D1 of the resistor and the resistor D1 of the negative of the current transformer, and the resistor D1 of the chip U1 of the resistor D1, and the current transformer, and the negative of the current transformer, The 5 pin and the 13 pin of the FT230XS conversion chip U7 are both connected with the voltage of the ground.

3. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication according to claim 2, wherein a pin 1 of the FT230XS conversion chip U7 is connected to a pin 3 of a TLP2362 photocoupler U9, a pin 1 of the TLP2362 photocoupler U9 is connected to one end of a resistor R13, a pin 6 is connected to a 3.3V voltage output end, a pin 5 is respectively connected to one end of a resistor R15 and an RXD of the SWM320VET7 chip, the pin 4 is grounded, the other end of the resistor R13 is connected to a driving voltage, and a voltage output end of a power circuit at the other end of the resistor R15 is connected to a voltage output end of the power circuit.

4. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 3, wherein a pin 4 of the FT230XS conversion chip U7 is connected to a pin 5 of a TLP2362 photocoupler U8 and one end of a resistor R14 respectively, a pin 6 of the TLP2362 photocoupler U8 is connected to a driving voltage, a pin 1 is connected to one end of a resistor R12, a pin 3 is connected to a TXD of the SWM320VET7 chip, a pin 4 is connected to a ground terminal voltage, the other end of the resistor R14 is connected to the driving voltage, and the other end of the resistor R12 is connected to a voltage output end of a power supply circuit.

5. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 4, wherein the CAN communication bus circuit comprises a MAX3051CAN transceiver chip U4, pins 1, 4 and 5 of the MAX3051CAN transceiver chip U4 are all connected to the control circuit, pins 8 and 2 are all grounded, pin 3 is connected to the output terminal of the power voltage, pin 6 is connected to the CAN low-speed bus, pin 7 is connected to the CAN high-speed bus, and a resistor R7 is connected in parallel between the CAN low-speed bus and the CAN high-speed bus.

6. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 5, wherein the number of DAC conversion circuits is matched with the number of PID adjustment constant current source circuits, each DAC conversion circuit comprises a second-order RC circuit, one end of the second-order RC circuit is connected with the PWM output end of the SWM320VET7 chip, the other end of the second-order RC circuit is connected with the positive-phase input end of an RS8557 operational amplifier U10, and the negative-phase input end and the output end of the RS8557 operational amplifier U10 are respectively connected with one end of a resistor R17 and a direct current signal output end.

7. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 6, wherein an 8 pin of the RS8557 operational amplifier is connected to an output terminal of a power supply voltage, a 2 pin is grounded, and the other end of the resistor R17 is grounded.

8. The multi-channel wide-range adjustment linear constant current driving circuit with CAN communication of claim 7, wherein the number of the PID adjustment constant current source circuits is 9, each PID adjustment constant current source circuit includes a resistor R18, one end of the resistor R18 is connected to a dc signal output terminal, the other end of the resistor R18 is connected to a non-inverting input terminal of an operational amplifier U11B, inverting input terminals of the operational amplifiers are respectively connected to one end of a resistor R19, one end of a capacitor C10, the other end of the capacitor C10 is respectively connected to an output terminal of the operational amplifier U11B, one end of a resistor R29, and one end of a resistor R30, the other end of the resistor R29 is connected to a base of an NPN triode Q1, the other end of the resistor R30 is connected to a base of an NPN triode Q2, a collector of the NPN triode Q1 is connected to a 9V voltage output terminal, and an emitter of the NPN triode Q1 is respectively connected to an emitter and a negative output terminal of the NPN transistor Q2, the collector of the NPN triode Q2 is connected to the 9V voltage output terminal, the other end of the resistor R19 is connected to the output terminal of the operational amplifier U11A, one end of the resistor R20, the other end of the resistor R20 is connected to the inverting input terminal of the operational amplifier U11A, one end of the resistor R21, the non-inverting input terminal of the operational amplifier U11A is connected to one end of the resistor R22 and one end of the resistor R23, the other end of the resistor R21 is connected to one end of the resistor R24 and the source of the NMOS transistor Q3, the other end of the resistor R23 is connected to the other end of the resistor R24, one end of the resistor R25, the other end of the resistor R25 is connected to the positive output terminal, the drain of the NMOS transistor Q3 is connected to one end of the resistor R26, the other end of the resistor R26 is grounded, the gate of the NMOS transistor Q3 is connected to one end of the resistor R27, the other end of the resistor R27 is connected to one end of the resistor R28 and the control output terminal, and the other end of the resistor R28 is grounded.