A drive protection circuit

Abstract

The application discloses a driving protection circuit applied to a MOS tube. The driving protection circuit comprises a gate driving module, a detection module and a logic judgment module. The gate driving module controls the MOS tube to be turned on or turned off according to a driving signal. The detection module is used for outputting a first trigger signal when the voltage of the MOS tube is detected to be greater than a first preset voltage, and is used for converting the working temperature of the MOS tube into a second detection voltage, outputting a second trigger signal when the second detection voltage is greater than a second preset voltage, and outputting a third trigger signal when the current of the MOS tube is detected to be greater than a preset current. The logic judgment module is used for outputting a protection signal according to the first trigger signal or the second trigger signal or the third trigger signal, so that the gate driving module controls the MOS tube to be turned off. The application can relieve the failure risk of the MOS tube in actual application.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a drive protection circuit. Background Technology

[0002] With the continuous development of electronic technology, power devices are increasingly widely used in various electronic devices. Among them, metal-oxide-semiconductor field-effect transistors (MOSFETs, or MOS transistors for short) have become one of the core components in power conversion circuits due to their excellent switching characteristics, high input impedance, and low on-resistance. In the application of MOSFETs, the gate driver is an important component to ensure their normal operation. It can provide a suitable drive signal to the gate of the MOSFET to realize the control of the MOSFET's turn-on and turn-off.

[0003] Although the gate driver plays a crucial role in the driving process of a MOSFET, current driving circuits have insufficient protection mechanisms. As a semiconductor device, a MOSFET can fail due to various factors during operation. Common failure modes include overcurrent, overvoltage, and overheating (thermal breakdown). Overcurrent causes the internal current density of the MOSFET to exceed its rated value, leading to device damage; overvoltage can break down the insulating layer of the MOSFET, causing device failure; and overheating may alter the internal structure of the MOSFET, reducing its performance or even causing thermal breakdown. Therefore, current MOSFETs face a high risk of failure in practical applications, affecting the reliability and lifespan of electronic devices. Utility Model Content

[0004] This application provides a drive protection circuit that can effectively protect MOSFETs and mitigate the failure risk faced by MOSFETs in practical applications.

[0005] This application provides a drive protection circuit for MOSFETs, the drive protection circuit comprising:

[0006] The gate drive module is connected to the gate of the MOSFET and is used to control the MOSFET to turn on or off according to the drive signal.

[0007] The detection module is connected to the MOSFET. The detection module is used to output a first trigger signal when the voltage of the MOSFET is detected to be greater than a first preset voltage, and to convert the operating temperature of the MOSFET into a second detection voltage. When the second detection voltage is greater than a second preset voltage, it outputs a second trigger signal, and when the current of the MOSFET is detected to be greater than a preset current, it outputs a third trigger signal.

[0008] The logic judgment module is connected to the detection module and the gate drive module. The logic judgment module is used to output a protection signal according to the first trigger signal, the second trigger signal, or the third trigger signal, so that the gate drive module controls the MOS transistor to disconnect.

[0009] In some embodiments of the drive protection circuit, the logic judgment module includes a trigger unit and a protection unit, the trigger unit being connected to the detection module and the protection unit respectively; the trigger unit is used to output a control signal to the protection unit according to a first trigger signal, a second trigger signal, or a third trigger signal, and the protection unit is used to output a protection signal to the gate drive module according to the control signal.

[0010] In some embodiments of the drive protection circuit, the detection module includes a voltage detection unit, a temperature detection unit, and a current detection unit.

[0011] The voltage detection unit is connected to the drain and gate of the MOSFET. The voltage detection unit is used to detect the voltage of the MOSFET to output a first detection voltage, and outputs a first trigger signal when the first detection voltage is greater than a first preset voltage. The temperature detection unit is used to convert the operating temperature of the MOSFET into a second detection voltage, and outputs a second trigger signal when the second detection voltage is greater than a second preset voltage. The current detection unit is connected to the source and gate of the MOSFET. The current detection unit is used to detect the current of the MOSFET to output a detection current, and outputs a third trigger signal when the detection current is greater than a preset current.

[0012] In some embodiments of the drive protection circuit, the triggering unit includes an OR gate, the first input terminal of the OR gate is connected to the detection module, the second input terminal of the OR gate is connected to the detection module, the third input terminal of the OR gate is connected to the detection module, and the output terminal of the OR gate is connected to the protection unit.

[0013] In some embodiments of the drive protection circuit, the protection unit includes an AND gate and a first switching transistor. The first input terminal of the AND gate is connected to the output terminal of the OR gate, the second input terminal of the AND gate is connected to an enable signal, the output terminal of the AND gate is connected to the first terminal of the first switching transistor, the second terminal of the first switching transistor is connected to the gate drive module, and the third terminal of the first switching transistor is grounded.

[0014] In some embodiments of the drive protection circuit, the voltage detection unit includes a first resistor, a second resistor, a third resistor, a first capacitor, a first operational amplifier, and a second operational amplifier. One end of the first resistor is connected to the drain of a MOSFET, and the other end of the first resistor is connected to one end of the second resistor. The other end of the second resistor is connected to one end of the third resistor and the non-inverting input of the first operational amplifier. The other end of the third resistor and one end of the first capacitor are both connected to the source of the MOSFET, and the other end of the first capacitor is connected to the other end of the second resistor. The inverting input of the first operational amplifier is connected to its output, and the output of the first operational amplifier is connected to the non-inverting input of the second operational amplifier. The inverting input of the second operational amplifier is used to connect to a first preset voltage, and the output of the second operational amplifier is connected to a logic judgment module.

[0015] In some embodiments of the drive protection circuit, the temperature detection unit includes a thermistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a third operational amplifier, and a fourth operational amplifier. One end of the thermistor is connected to a contact point, and the other end of the thermistor is connected to one end of the fourth resistor and one end of the fifth resistor. The other end of the fourth resistor is grounded. One end of the fifth resistor is connected to the non-inverting input of the third operational amplifier. The inverting input of the third operational amplifier is connected to one end of the sixth resistor and one end of the seventh resistor. The other end of the sixth resistor is grounded. The other end of the seventh resistor is connected to the output of the third operational amplifier. The output of the third operational amplifier is connected to the non-inverting input of the fourth operational amplifier. The inverting input of the fourth operational amplifier is connected to a second preset voltage. The output of the fourth operational amplifier is connected to a logic judgment module.

[0016] In some embodiments of the drive protection circuit, the current detection unit includes a sampling resistor, an eighth resistor, a ninth resistor, a tenth resistor, a fifth operational amplifier, and a sixth operational amplifier. One end of the sampling resistor is connected to the source of the MOSFET, and the other end of the sampling resistor is grounded. One end of the eighth resistor is connected to the sampling resistor, and the other end of the eighth resistor is connected to the non-inverting input of the fifth operational amplifier. One end of the ninth resistor is grounded, and the other end of the ninth resistor is connected to the inverting input of the fifth operational amplifier. The output of the fifth operational amplifier is connected to the non-inverting input of the sixth operational amplifier. The inverting input of the sixth operational amplifier is connected to a logic judgment module for connecting a preset current and the output of the sixth operational amplifier.

[0017] In some embodiments of the drive protection circuit, the gate drive module is a negative voltage drive module.

[0018] In some embodiments of the drive protection circuit, the gate drive module includes a second switch, a third switch, a second capacitor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, and a fourteenth resistor. The first terminals of the second and third switches are both connected to the drive signal through the eleventh resistor. The second terminal of the second switch is energized. The third terminal of the second switch is connected to the second terminal of the third switch. The third terminal of the third switch is grounded. One end of the second capacitor is connected to the third terminal of the second switch. The other end of the second capacitor is connected to the gate of the MOSFET through the twelfth resistor. One end of the thirteenth resistor is connected to the gate of the MOSFET. The other end of the thirteenth resistor is connected to the detection module. One end of the fourteenth resistor is energized. The other end of the fourteenth resistor is connected to the drain of the MOSFET. The first terminals of the second and third switches are also connected to the logic judgment module.

[0019] This application provides a drive protection circuit for a MOSFET. The drive protection circuit includes a gate drive module, a detection module, and a logic judgment module. The gate drive module controls the MOSFET to turn on or off based on a drive signal. The detection module outputs a first trigger signal when the voltage of the MOSFET is detected to be greater than a first preset voltage, and converts the operating temperature of the MOSFET into a second detection voltage. When the second detection voltage is greater than a second preset voltage, it outputs a second trigger signal, and when the current of the MOSFET is detected to be greater than a preset current, it outputs a third trigger signal. The logic judgment module outputs a protection signal based on the first, second, or third trigger signals, causing the gate drive module to control the MOSFET to turn off. By simultaneously setting a detection module to protect the MOSFET, this application ensures that the MOSFET is turned off under overvoltage, overcurrent, or high-temperature conditions, thereby improving the reliability of the MOSFET. Attached Figure Description

[0020] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0021] Figure 1 This is a structural block diagram of the drive protection circuit provided in an embodiment of this application.

[0022] Figure 2 The block diagram of the detection module and logic judgment module in the drive protection circuit provided in the embodiments of this application is shown.

[0023] Figure 3 The circuit diagram of the logic judgment module in the drive protection circuit provided in the embodiment of this application.

[0024] Figure 4 The circuit diagram of the voltage detection unit in the drive protection circuit provided in the embodiment of this application.

[0025] Figure 5 The circuit diagram of the temperature detection unit in the drive protection circuit provided in the embodiment of this application.

[0026] Figure 6 The circuit diagram of the gate drive module in the drive protection circuit provided in the embodiment of this application.

[0027] Figure 7 The circuit diagram of the current detection unit in the drive protection circuit provided in the embodiment of this application. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features thus defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0030] Please see Figure 1 This embodiment provides a drive protection circuit applied to a MOSFET to protect it. Specifically, the drive protection circuit includes a gate drive module 200, a detection module 300, and a logic judgment module 400. The gate drive module 200 is connected to the gate of the MOSFET 100 and is used to control the MOSFET 100 to turn on or off according to a drive signal. The detection module 300 is connected to the MOSFET. The logic judgment module 400 is connected to both the detection module 300 and the gate drive module 200.

[0031] The detection module 300 is used to detect the voltage of the MOSFET 100 and output a first detection voltage, and output a first trigger signal when the first detection voltage is greater than a first preset voltage. The detection module 300 is also used to convert the operating temperature of the MOSFET 100 into a second detection voltage, and output a second trigger signal when the second detection voltage is greater than a second preset voltage. The detection module 300 is also used to detect the current of the MOSFET 100 and output a detection current, and output a third trigger signal when the detection current is greater than a preset current. The logic judgment module 400 is used to output a protection signal to the gate drive module 200 according to the first, second, or third trigger signal, so that the gate drive module 200 controls the MOSFET 100 to disconnect. By setting the detection module 300 to protect the MOSFET 100 in this application, it is possible to ensure that the MOSFET disconnects when operating under overvoltage, overcurrent, or high temperature conditions, thereby improving the reliability of the MOSFET 100. Please refer to [link to relevant documentation]. Figure 2 In some embodiments, the logic judgment module 400 includes a trigger unit 410 and a protection unit 420. The trigger unit 410 is connected to both the detection module 300 and the protection unit 420. The trigger unit 410 outputs a control signal to the protection unit 420 based on a first trigger signal, a second trigger signal, or a third trigger signal. The protection unit 420 outputs a protection signal to the gate drive module 200 based on the control signal. In this embodiment, the trigger unit 410 can trigger protection of the MOS transistor 100 upon receiving any one of the first, second, or third trigger signals, which improves the comprehensiveness of protection.

[0032] Please continue reading. Figure 2 In some embodiments, the detection module 300 includes a voltage detection unit 310, a temperature detection unit 320, and a current detection unit 330; the voltage detection unit 310, the temperature detection unit 320, and the current detection unit 330 are all connected to the logic judgment module 400, the voltage detection unit 310 is connected to the drain and gate of the MOS transistor, and the current detection unit 330 is connected to the source and gate of the MOS transistor.

[0033] The voltage detection unit 310 detects the voltage of the MOSFET to output a first detection voltage, and outputs a first trigger signal when the first detection voltage is greater than a first preset voltage. The temperature detection unit 320 converts the operating temperature of the MOSFET into a second detection voltage, and outputs a second trigger signal when the second detection voltage is greater than a second preset voltage. The current detection unit 330 detects the current of the MOSFET to output a detection current, and outputs a third trigger signal when the detection current is greater than a preset current. By simultaneously setting the voltage detection unit 310, temperature detection unit 320, and current detection unit 330 to protect the MOSFET 100, this application ensures that the MOSFET is disconnected when operating under overvoltage, overcurrent, or high temperature conditions, thereby improving the reliability of the MOSFET 100.

[0034] Please see Figure 3 In one embodiment, the trigger unit 410 includes an OR gate OR1. The first input terminal of the OR gate OR1 is connected to the detection module 300, the second input terminal of the OR gate OR1 is connected to the detection module 300, the third input terminal of the OR gate OR1 is connected to the detection module 300, and the output terminal of the OR gate OR1 is connected to the protection unit 420. In this embodiment, the trigger unit 410 is formed by setting the OR gate OR1. When the detection module 300 outputs any trigger signal, the protection of the MOS transistor 100 can be triggered.

[0035] In one embodiment, the protection unit 420 includes an AND gate AND1 and a first switch Q1. The first input of the AND gate AND1 is connected to the output of an OR gate OR1. An enable signal is received at the second input of the AND gate AND1. The output of the AND gate AND1 is connected to the first terminal of the first switch Q1. The second terminal of the first switch Q1 is connected to the gate drive module 200, and the third terminal of the first switch Q1 is grounded. In this embodiment, the AND gate AND1 outputs a control signal to the first switch Q1 according to the input enable signal and any trigger signal, thereby turning on the first switch Q1 to provide a protection signal to the gate drive module 200 and protect the MOSFET 100.

[0036] Please see Figure 4In one embodiment, the voltage detection unit 310 includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a first operational amplifier OP1, and a second operational amplifier OP2. One end of the first resistor R1 is connected to the drain of the MOSFET 100, and the other end of the first resistor R1 is connected to one end of the second resistor R2. The other end of the second resistor R2 is connected to one end of the third resistor R3 and the non-inverting input of the first operational amplifier OP1. The other end of the third resistor R3 and one end of the first capacitor C1 are both connected to the source of the MOSFET 100, and the other end of the first capacitor C1 is connected to the other end of the second resistor R2. The inverting input of the first operational amplifier OP1 is connected to the output of the first operational amplifier OP1, and the output of the first operational amplifier OP1 is connected to the non-inverting input of the second operational amplifier OP2. The inverting input of the second operational amplifier OP2 is used to connect to a first preset voltage, and the output of the second operational amplifier OP2 is connected to the logic judgment module 400. In this circuit, the first capacitor C1 is a decoupling capacitor. The voltage of the MOSFET 100 is attenuated and then decoupled before being fed into the first operational amplifier OP1 for voltage following processing. This allows for impedance transformation and ensures that the input and output remain consistent, which improves the reliability of the detected voltage. Subsequently, the second operational amplifier OP2 compares the voltage output from the first operational amplifier OP1 with a first preset voltage to trigger overvoltage protection and achieve voltage monitoring.

[0037] Please see Figure 5 In one embodiment, the temperature detection unit 320 includes a thermistor RANT, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a third operational amplifier OP3, and a fourth operational amplifier OP4. One end of the thermistor RANT is energized, and the other end of the thermistor RANT is connected to one end of the fourth resistor R4 and one end of the fifth resistor R5. The other end of the fourth resistor R4 is grounded. One end of the fifth resistor R5 is connected to the non-inverting input of the third operational amplifier OP3. The inverting input of the third operational amplifier OP3 is connected to one end of the sixth resistor R6 and one end of the seventh resistor R7. The other end of the sixth resistor R6 is grounded. The other end of the seventh resistor R7 is connected to the output of the third operational amplifier OP3. The output of the third operational amplifier OP3 is connected to the non-inverting input of the fourth operational amplifier OP4. The inverting input of the fourth operational amplifier OP4 is connected to a second preset voltage. The output of the fourth operational amplifier OP4 is connected to the logic judgment module 400.

[0038] In this embodiment, a connection is established between the thermistor RANT and the MOSFET. The thermistor RANT converts the temperature of the MOSFET into an electrical signal, which is amplified by the third operational amplifier OP3. The third operational amplifier OP3 then compares the amplified voltage with a second preset voltage. If the voltage output by the third operational amplifier OP3 is greater than the second preset voltage, the third operational amplifier OP3 outputs a high level as a second trigger signal, thereby realizing the over-temperature protection of the MOSFET 100.

[0039] Please see Figure 6 and Figure 7 In one embodiment, the current detection unit 330 includes a sampling resistor Rcs, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a fifth operational amplifier OP5, and a sixth operational amplifier OP6. One end of the sampling resistor Rcs is connected to the source of the MOS transistor 100, and the other end of the sampling resistor Rcs is grounded. One end of the eighth resistor R8 is connected to the sampling resistor Rcs, and the other end of the eighth resistor R8 is connected to the non-inverting input of the fourth operational amplifier OP4. One end of the ninth resistor R9 is grounded, and the other end of the ninth resistor R9 is connected to the inverting input of the fifth operational amplifier OP5. The output of the fifth operational amplifier OP5 is connected to the non-inverting input of the sixth operational amplifier OP6. The inverting input of the sixth operational amplifier OP6 is connected to the logic judgment module 400 for connecting a preset current and the output of the sixth operational amplifier OP6.

[0040] In this embodiment, the current of MOSFET 100 is sampled by setting a sampling resistor Rcs to obtain a sampling current. The sampling current is amplified by the fifth operational amplifier OP5 and then output to the sixth operational amplifier OP6. The comparator formed by the sixth operational amplifier OP6 is compared with a preset current. If the sampling current is greater than the preset current, a high level is output as a third trigger signal to realize overcurrent protection for MOSFET 100.

[0041] Please continue reading. Figure 6In one embodiment, the gate driving module is a negative voltage driving module. Specifically, the gate driving module 200 includes a second switch Q2, a third switch Q3, a second capacitor C2, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, and a fourteenth resistor R14. The first terminals of both the second and third switches Q2 are connected to the driving signal (PWM-IN signal terminal in this embodiment) through the eleventh resistor R11. The second terminal of the second switch Q2 is energized, and the third terminal of the second switch Q2 is connected to the second terminal of the third switch Q3. The third terminal of the third switch Q3 is connected to... One end of the second capacitor C2 is connected to the third end of the second switch Q2, and the other end of the second capacitor C2 is connected to the gate of the MOSFET 100 through the twelfth resistor R12. One end of the thirteenth resistor R13 is connected to the gate of the MOSFET 100, and the other end of the thirteenth resistor R13 is connected to one end of the sampling resistor Rcs. One end of the fourteenth resistor R14 is energized, and the other end of the fourteenth resistor R14 is connected to the drain of the MOSFET 100. The first ends of the second switch Q2 and the third switch Q3 are also connected to the second end of the first switch Q1 (the Down-Control signal end in this embodiment).

[0042] In this embodiment, the second switch Q2 and the third switch Q3, two complementary switches, form a push-pull circuit. The two switches do not conduct simultaneously. When the second switch Q2 is on, the output of the push-pull circuit is VCC; when the third switch Q3 is on, the output of the push-pull circuit is grounded. A negative voltage generation circuit is formed by setting a second capacitor C2. During the charging phase, the second capacitor C2 is connected to VCC; during the switching phase, the input of the second capacitor C2 is grounded, and the output forms a negative voltage, realizing negative voltage turn-off drive. This accelerates the turn-off of driven devices such as MOSFET 100, thereby improving turn-off reliability. When OR gate OR1 receives any trigger signal, AND gate AND1 outputs a control signal to control the first switch Q1 to conduct. After the first switch Q1 conducts, the Down-Control signal terminal is pulled low, forcibly pulling the drive signal input to the PWM-IN signal terminal low to shut down the drive output, thus protecting MOSFET 100.

[0043] This application also provides a drive protection circuit, which will not be described in detail here, as the drive protection circuit has been described in detail above.

[0044] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0045] The driving protection circuit provided in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A drive protection circuit applied to a MOSFET, characterized in that, The drive protection circuit includes: A gate driving module is connected to the gate of the MOS transistor, and the gate driving module is used to control the MOS transistor to be turned on or off according to a driving signal; The detection module is connected to the MOSFET. The detection module is used to output a first trigger signal when the voltage of the MOSFET is detected to be greater than a first preset voltage, and to convert the operating temperature of the MOSFET into a second detection voltage. When the second detection voltage is greater than a second preset voltage, the detection module outputs a second trigger signal, and when the current of the MOSFET is detected to be greater than a preset current, the detection module outputs a third trigger signal. A logic judgment module is connected to the detection module and the gate driving module. The logic judgment module is used to output a protection signal according to the first trigger signal, the second trigger signal, or the third trigger signal, so that the gate driving module controls the MOS transistor to disconnect.

2. The drive protection circuit according to claim 1, characterized in that, The logic judgment module includes a trigger unit and a protection unit. The trigger unit is connected to the detection module and the protection unit respectively. The trigger unit is used to output a control signal to the protection unit according to the first trigger signal, the second trigger signal, or the third trigger signal. The protection unit is used to output a protection signal to the gate drive module according to the control signal.

3. The drive protection circuit according to claim 1, characterized in that, The detection module includes a voltage detection unit, a temperature detection unit, and a current detection unit; The voltage detection unit is connected to the drain and gate of the MOSFET. The voltage detection unit is used to detect the voltage of the MOSFET to output a first detection voltage, and output a first trigger signal when the first detection voltage is greater than a first preset voltage. The temperature detection unit is used to convert the operating temperature of the MOSFET into a second detection voltage, and output a second trigger signal when the second detection voltage is greater than a second preset voltage. The current detection unit is connected to the source and gate of the MOSFET. The current detection unit is used to detect the current of the MOSFET to output a detection current, and output a third trigger signal when the detection current is greater than a preset current.

4. The drive protection circuit according to claim 2, characterized in that, The triggering unit includes an OR gate, the first input terminal of which is connected to the detection module, the second input terminal of which is connected to the detection module, the third input terminal of which is connected to the detection module, and the output terminal of which is connected to the protection unit.

5. The drive protection circuit according to claim 4, characterized in that, The protection unit includes an AND gate and a first switching transistor. The first input terminal of the AND gate is connected to the output terminal of the OR gate. The second input terminal of the AND gate is connected to an enable signal. The output terminal of the AND gate is connected to the first terminal of the first switching transistor. The second terminal of the first switching transistor is connected to the gate driving module. The third terminal of the first switching transistor is grounded.

6. The drive protection circuit according to claim 3, characterized in that, The voltage detection unit includes a first resistor, a second resistor, a third resistor, a first capacitor, a first operational amplifier, and a second operational amplifier. One end of the first resistor is connected to the drain of the MOSFET, and the other end of the first resistor is connected to one end of the second resistor. The other end of the second resistor is connected to one end of the third resistor and the non-inverting input of the first operational amplifier. The other end of the third resistor and one end of the first capacitor are both connected to the source of the MOSFET, and the other end of the first capacitor is connected to the other end of the second resistor. The inverting input of the first operational amplifier is connected to its output, and the output of the first operational amplifier is connected to the non-inverting input of the second operational amplifier. The inverting input of the second operational amplifier is used to connect to the first preset voltage, and the output of the second operational amplifier is connected to the logic judgment module.

7. The drive protection circuit according to claim 3, characterized in that, The temperature detection unit includes a thermistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a third operational amplifier, and a fourth operational amplifier. One end of the thermistor is connected to a contact point, and the other end of the thermistor is connected to one end of the fourth resistor and one end of the fifth resistor. The other end of the fourth resistor is grounded. One end of the fifth resistor is connected to the non-inverting input of the third operational amplifier. The inverting input of the third operational amplifier is connected to one end of the sixth resistor and one end of the seventh resistor. The other end of the sixth resistor is grounded. The other end of the seventh resistor is connected to the output of the third operational amplifier. The output of the third operational amplifier is connected to the non-inverting input of the fourth operational amplifier. The inverting input of the fourth operational amplifier is connected to a second preset voltage. The output of the fourth operational amplifier is connected to the logic judgment module.

8. The drive protection circuit according to claim 3, characterized in that, The current detection unit includes a sampling resistor, an eighth resistor, a ninth resistor, a tenth resistor, a fifth operational amplifier, and a sixth operational amplifier. One end of the sampling resistor is connected to the source of the MOS transistor, and the other end of the sampling resistor is grounded. One end of the eighth resistor is connected to the sampling resistor, and the other end of the eighth resistor is connected to the non-inverting input terminal of the fifth operational amplifier. One end of the ninth resistor is grounded, and the other end of the ninth resistor is connected to the inverting input terminal of the fifth operational amplifier. The output terminal of the fifth operational amplifier is connected to the non-inverting input terminal of the sixth operational amplifier. The inverting input terminal of the sixth operational amplifier is connected to the logic judgment module for connecting a preset current. The output terminal of the sixth operational amplifier is connected to the logic judgment module.

9. The drive protection circuit according to any one of claims 1-8, characterized in that, The gate drive module is a negative voltage drive module.

10. The drive protection circuit according to claim 9, characterized in that, The gate driving module includes a second switch, a third switch, a second capacitor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, and a fourteenth resistor. The first terminals of the second and third switches are both connected to a drive signal via the eleventh resistor. The second terminal of the second switch is energized. The third terminal of the second switch is connected to the second terminal of the third switch, and the third terminal of the third switch is grounded. One end of the second capacitor is connected to the third terminal of the second switch, and the other end of the second capacitor is connected to the gate of the MOSFET via the twelfth resistor. One end of the thirteenth resistor is connected to the gate of the MOSFET, and the other end of the thirteenth resistor is connected to the detection module. One end of the fourteenth resistor is energized, and the other end of the fourteenth resistor is connected to the drain of the MOSFET. The first terminals of the second and third switches are also connected to the logic judgment module.

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