Switching tube driving protection circuit and half-bridge circuit system

Abstract

The utility model discloses a switching tube driving protection circuit, and the circuit comprises a comparator module which is used for generating a comparison signal based on a driving signal of any power tube of a bridge circuit and a reference voltage signal; the isolation module is used for isolating the comparison signal and then outputting an isolated comparison signal; and the DSP controller is used for cutting off the DSP driving signal when the isolation comparison signal is different from the DSP driving signal. The utility model also relates to a half-bridge circuit system comprising the switch tube driving protection circuit. According to the switch tube driving protection circuit provided by the utility model, whether driving abnormity occurs is judged by comparing the power tube driving signal with the DSP driving signal, so that when the driving abnormity occurs, the DPS driving signal is closed, and the power tube is prevented from being damaged. And the whole circuit is ingenious in design, and the bridge circuit does not need to be changed, so that the circuit is suitable for various bridge circuit scenes, and the implementation cost is low.

Description

Technical Field

[0001] The utility model relates to the field of switch tube driving, and more specifically, to a switch tube driving protection circuit and a half-bridge circuit system comprising the switch tube driving protection circuit. Background Art

[0002] As a circuit commonly used in AC / DC conversion, the half-bridge circuit has been widely used in various power modules. Figure 1 FIG. 2 shows a schematic block diagram of a half-bridge circuit in the prior art. Figure 1 As shown, the main power tubes Q2 and Q4 are driven by a combination of a driver chip module, a transformer, and a switch tube drive unit, that is, the DSP drive signals DRV_H and DRV_L sent from the DSP controller are respectively passed through the driver chip module, the transformer T1, and the switch tube drive unit to form power tube drive signals DRV_H1 and DRV_L1, and are respectively sent to the control ends of the main power tubes Q2 and Q4. In this process, when the switch tube in the switch tube drive unit uses the SIC switch tube, it is easily interfered by the secondary side signal of the transformer T1, which affects its switch reliability, further affects the control of the main power tubes Q2 and Q4, and causes the main power tubes Q2 and Q4 to be damaged due to excessive loss. Utility Model Content

[0003] The technical problem to be solved by the utility model is that, in view of the above-mentioned defects of the prior art, a switch tube drive protection circuit and a half-bridge circuit system including the switch tube drive protection circuit are provided, which determines whether a drive abnormality occurs by comparing a power tube drive signal and a DSP drive signal, and turns off the DPS drive signal when a drive abnormality occurs, thereby preventing damage to the power tube.

[0004] The technical solution adopted by the utility model to solve the technical problem is: construct a switch tube drive protection circuit, including:

[0005] A comparator module, used for generating a comparison signal based on any power tube drive signal of the bridge circuit and a reference voltage signal;

[0006] An isolation module, used for isolating the comparison signal and then outputting an isolated comparison signal;

[0007] The DSP controller is used to cut off the DSP driving signal when the isolation comparison signal and the DSP driving signal are different.

[0008] In the switch tube driving protection circuit described in the utility model, the comparator module includes a comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor;

[0009] The non-phase input terminal of the comparator is connected to the control terminal of any power tube of the bridge circuit via the first resistor to receive the power tube drive signal, and is connected to the first working voltage via the second resistor; the inverting input terminal of the comparator is connected to the first working voltage via the third resistor, and is grounded via the fourth resistor; the positive voltage electrode of the comparator is connected to the first working voltage, and the negative voltage electrode is grounded; the fifth resistor is connected between the non-phase input terminal and the output terminal of the comparator; the output terminal of the comparator outputs the comparison signal.

[0010] In the switch tube driving protection circuit described in the utility model, the isolation module includes a digital isolator and a sixth resistor; the first power supply terminal of the digital isolator is connected to the second working voltage, and the input terminal is connected to the output terminal of the comparator to receive the comparison signal; the sixth resistor is connected between the first power supply terminal of the digital isolator and the output terminal of the comparator; the output terminal of the digital isolator outputs the isolation comparison signal.

[0011] The switch tube driving protection circuit of the present invention further includes a seventh resistor, which is connected between the output end of the comparator and the input end of the digital isolator.

[0012] Another technical solution adopted by the utility model to solve its technical problem is to construct a half-bridge circuit system, including a driving chip module, a transformer, a first switch tube driving unit, a second switch tube driving unit, a first main power tube and a second main power tube, and a switch tube driving protection circuit; the switch tube driving protection circuit includes: a comparator module, which is used to generate a comparison signal based on the power tube driving signal and the reference voltage signal of the half-bridge circuit; an isolation module, which is used to isolate the comparison signal and then output an isolated comparison signal; a DSP controller, which is used to cut off the DSP driving signal when the isolated comparison signal and the DSP driving signal are different.

[0013] In the half-bridge circuit system described in the utility model, the comparator module includes a comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; the non-phase input terminal of the comparator is connected to the control terminal of any power tube of the half-bridge circuit via the first resistor to receive the power tube drive signal, and is connected to the first working voltage via the second resistor; the inverting input terminal of the comparator is connected to the first working voltage via the third resistor, and is grounded via the fourth resistor; the positive voltage electrode of the comparator is connected to the first working voltage, and the negative voltage electrode is grounded; the fifth resistor is connected between the non-phase input terminal and the output terminal of the comparator; the output terminal of the comparator outputs the comparison signal;

[0014] The isolation module includes a digital isolator and a sixth resistor; the first power supply terminal of the digital isolator is connected to the second working voltage, and the input terminal is connected to the output terminal of the comparator to receive the comparison signal; the sixth resistor is connected between the first power supply terminal of the digital isolator and the output terminal of the comparator; the output terminal of the digital isolator outputs the isolation comparison signal.

[0015] In the half-bridge circuit system described in the utility model, the driving chip module includes a driving chip, an eighth resistor, a ninth resistor, a first capacitor and a tenth resistor. The first input end of the driving chip receives a first DSP driving signal via the eighth resistor, and the second input end of the driving chip receives a second DSP driving signal via the ninth resistor. The first output end of the driving chip is connected to the first end of the primary coil of the transformer via the first capacitor, and the second output end of the driving chip is connected to the second end of the primary coil of the transformer via the tenth resistor; the first secondary coil of the transformer is connected to the first main power tube via the first switch tube driving unit, and the second secondary coil of the transformer is connected to the second main power tube via the first switch tube driving unit; the control end of the first main power tube receives the first power tube driving signal via the first switch tube driving unit; and the control end of the second main power tube receives the second power tube driving signal via the second switch tube driving unit.

[0016] In the half-bridge circuit system described in the present invention, the non-phase input end of the comparator is connected to the control end of the first main power tube via the first resistor to receive the first power tube drive signal or connected to the control end of the second main power tube to receive the second power tube drive signal, and generates a first comparison signal or a second comparison signal respectively.

[0017] In the half-bridge circuit system described in the present invention, the input end of the digital isolator is connected to the output end of the comparator to receive the first comparison signal or the second comparison signal; the output end of the digital isolator outputs the first isolation comparison signal or the second isolation comparison signal.

[0018] In the half-bridge circuit system described in the present utility model, the DSP controller is used to cut off the first DSP drive signal and the second DSP drive signal when the first isolation comparison signal and the first DSP drive signal are different, or to cut off the first DSP drive signal and the second DSP drive signal when the second isolation comparison signal and the second DSP drive signal are different.

[0019] The switch tube drive protection circuit of the utility model is implemented to determine whether a drive abnormality occurs by comparing the power tube drive signal and the DSP drive signal, so that when a drive abnormality occurs, the DPS drive signal is turned off to prevent damage to the power tube. In addition, the entire circuit design is ingenious, and there is no need to modify the bridge circuit itself, so it is suitable for various bridge circuit scenarios and has low implementation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0021] Figure 1 A schematic block diagram of a half-bridge circuit in the prior art is shown;

[0022] Figure 2 It is a principle block diagram of a preferred embodiment of the switch tube driving protection circuit of the utility model;

[0023] Figure 3 It is a circuit diagram of a preferred embodiment of a comparator module and an isolation module of a switch tube driving protection circuit of the utility model;

[0024] Figure 4 The utility model is a circuit diagram of a half-bridge circuit suitable for the switch tube drive protection circuit. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0026] Figure 2 This is the principle block diagram of the switch tube drive protection circuit of the utility model. Figure 2 As shown, the switch tube drive protection circuit of the utility model includes a comparator module 100, an isolation module 200 and a DSP controller 300. The switch tube drive protection circuit of the utility model is preferably suitable for Figure 1 Of course, the switch tube drive protection circuit of the present invention can also be applied to any other suitable bridge circuit or power tube circuit. As mentioned above, the DSP drive signals DRV_H and DRV_L issued by the DSP controller 300 are respectively transmitted through the drive chip module, the transformer T1 and the switch tube drive unit to form the power tube drive signals DRV_H1 and DRV_L1, and are respectively sent to the control ends of the main power tubes Q2 and Q4.

[0027] The comparator module 100 is used to generate a comparison signal based on any power tube drive signal of the bridge circuit and a reference voltage signal. Figure 1It can be known that one end of the comparator module 100 can be connected to the control end of the main power tube Q2 or the main power tube Q4 to receive the power tube drive signal DRV_H1 or DRV_L1 of the main power tube Q2 or the main power tube Q4. In this embodiment, we only illustrate the power tube drive signal DRV_H1 of the main power tube Q4. Those skilled in the art know that the process and principle of the power tube drive signal DRV_L1 of the main power tube Q2 are similar, so they will not be repeated here.

[0028] The comparator module 100 generates a comparison signal DRV_H11 based on the reference voltage signal of the power tube drive signal DRV_H1 of the main power tube Q4. The isolation module 200 is used to receive the comparison signal DRV_H11 from the comparator module and then isolate it, and then output an isolation comparison signal DRV_PROTECT. The DSP controller 300 is connected in communication with the isolation module 200 to receive the isolation comparison signal DRV_PROTECT, and compares the received isolation comparison signal DRV_PROTECT with the power tube drive signal DRV_H of the main power tube Q4 generated by it. If the two are the same, it means that the entire circuit is normal, otherwise it means that the circuit is abnormal and there may be problems with the drive logic. At this time, the DSP controller stops sending the DSP drive signals DRV_H and DRV_L, and the power tubes Q4 and Q2 both stop working. This can prevent damage caused by the continuous operation of the power tube when a drive abnormality occurs.

[0029] In a preferred embodiment of the present utility model, the comparator module 100 can be implemented by any suitable comparator chip or circuit. The isolation module 200 can be implemented by any suitable optocoupler isolation module or digital isolator. The DSP controller 300 can also be implemented by any known DSP controller in the prior art.

[0030] The switch tube drive protection circuit of the utility model is implemented to determine whether a drive abnormality occurs by comparing the power tube drive signal and the DSP drive signal, so that when a drive abnormality occurs, the DPS drive signal is turned off to prevent damage to the power tube. The entire circuit design is ingenious and can be implemented using common devices without modifying the bridge circuit itself. Therefore, it is suitable for various bridge circuit scenarios and has low implementation cost.

[0031] Figure 3 FIG. 1 is a circuit diagram of a preferred embodiment of a comparator module and an isolation module of a switch tube drive protection circuit of the utility model. Figure 3As shown, the switch tube drive protection circuit of the utility model includes a comparator U108-B module 100, an isolation module 200 and a DSP controller 300. The comparator U108-B module 100 includes a comparator U108-B, a resistor R18, a resistor R23, a resistor R19, a resistor R20 and a resistor R24. The positive input terminal of the comparator U108-B is connected to the control terminal of any power tube of the bridge circuit (such as Figure 3 As shown, the control end of the main power tube Q4 receives the power tube drive signal DRV_H1 and is connected to the working voltage VCC1 via the resistor R23; the inverting input end of the comparator U108-B is connected to the working voltage VCC1 via the resistor R19 and is grounded via the resistor R20; the positive voltage pole of the comparator U108-B is connected to the working voltage VCC1 and the negative voltage pole is grounded; the resistor R24 ​​is connected between the non-inverting input end and the output end of the comparator U108-B; the output end of the comparator U108-B outputs the comparison signal DRV_H11.

[0032] The isolation module 200 includes a digital isolator U2 and a resistor R21; the first power supply terminal of the digital isolator U2 is connected to the working voltage +3V, and the input terminal is connected to the output terminal of the comparator U108-B to receive the comparison signal DRV_H11; the resistor R21 is connected between the first power supply terminal of the digital isolator U2 and the output terminal of the comparator U108-B; the output terminal of the digital isolator U2 outputs the isolation comparison signal DRV_H11. Preferably, a resistor R22 is connected between the output terminal of the comparator U108-B and the input terminal of the digital isolator U2.

[0033] The DSP controller 300 is connected in communication with the isolation module 200 to receive the isolation comparison signal DRV_PROTECT, and compares the received isolation comparison signal DRV_PROTECT with the power tube drive signal DRV_H of the main power tube Q4 generated by it. If the two are the same, it means that the entire circuit is normal, otherwise it means that the circuit is abnormal and there may be a problem with the drive logic. At this time, the DSP controller stops sending the DSP drive signals DRV_H and DRV_L, and the power tubes Q4 and Q2 both stop working. This can prevent damage caused by the continuous operation of the power tube when a drive abnormality occurs.

[0034] The following will be combined Figure 2-3 The principle of the switch tube driving protection circuit of the present invention is further explained as follows.

[0035] The DSP controller sends out DSP drive signals DRV_H and DRV_L, and the DSP drive signal is a high level signal at this time. At this time, the power tube drive signal DRV_H1 received by the power tube Q4 and the power tube drive signal DRV_L1 received by the power tube Q2 are both high levels. The power tube drive signal DRV_H1 received by the power tube Q4 is input into the comparator for comparison, and the generated comparison signal DRV_H11 is also high level. Then the isolation comparison signal DRV_PROTECT generated after isolation by the digital isolator is also high level. At this time, the isolation comparison signal DRV_PROTECT is returned to the I / O port of the DSP controller. If the isolation comparison signal DRV_PROTECT received by the I / O port of the DSP controller is high level and the DSP drive signal DRV_H sent by the DSP controller is also high level, that is, the two are the same, it is considered that the drive is normal. If the isolation comparison signal DRV_PROTECT received by the I / O port of the DSP controller is high level and the DSP drive signal DRV_H sent by the DSP controller is low level at this time, it is considered that the drive is abnormal. Of course, it is also possible that the DSP controller sends out DSP drive signals DRV_H and DRV_L, and the DSP drive signal is a low level signal at this time. At this time, the power tube drive signal DRV_H1 received by the power tube Q4 and the power tube drive signal DRV_L1 received by the power tube Q2 are both low levels. The power tube drive signal DRV_H1 received by the power tube Q4 is input into the comparator for comparison, and the generated comparison signal DRV_H11 is also low level. Then the isolation comparison signal DRV_PROTECT generated after isolation by the digital isolator is also low level. At this time, the isolation comparison signal DRV_PROTECT is returned to the I / O port of the DSP controller. If the isolation comparison signal DRV_PROTECT received by the I / O port of the DSP controller is low level and the DSP drive signal DRV_H sent by the DSP controller is also low level, that is, the two are the same, it is considered that the drive is normal. If the isolation comparison signal DRV_PROTECT received by the I / O port of the DSP controller is high level and the DSP drive signal DRV_H sent by the DSP controller is low level, it is considered that the drive is abnormal. In the above two driving abnormal logics, the DSP controller stops sending the DSP driving signals DRV_H and DRV_L, and the power tubes Q4 and Q2 both stop working, which can prevent damage caused by the power tubes continuing to work when driving abnormalities occur.

[0036] The switch tube drive protection circuit of the utility model is implemented to determine whether a drive abnormality occurs by comparing the power tube drive signal and the DSP drive signal, so that when a drive abnormality occurs, the DPS drive signal is turned off to prevent damage to the power tube. In addition, the entire circuit design is ingenious, and there is no need to modify the bridge circuit itself, so it is suitable for various bridge circuit scenarios and has low implementation cost.

[0037] Figure 4 This is a circuit diagram of a half-bridge circuit applicable to the switch tube drive protection circuit of the utility model. Figure 4 The half-bridge circuit shown and Figure 2-3 The switch tube drive protection circuit shown can obtain the half-bridge circuit system of the preferred embodiment of the utility model. The half-bridge circuit system includes a driver chip module, a transformer, a first switch tube drive unit, a second switch tube drive unit, a first main power tube and a second main power tube, and the aforementioned switch tube drive protection circuit. For the specific implementation method and principle of the switch tube drive protection circuit, please refer to Figure 2-3 The embodiments shown will not be described again here.

[0038] The preferred drive chip module, transformer, first switch tube drive unit, second switch tube drive unit, main power tube Q4 and main power tube Q2 of the half-bridge circuit system of the present invention are described below. Figure 4 As shown, the driver chip U1 module includes a driver chip U1, a resistor R1, a resistor R2, a capacitor C4 and a resistor R5. The first input end of the driver chip U1 receives the DSP drive signal DRV_H through the resistor R1, and the second input end of the driver chip U1 receives the DSP drive signal DRV_L through the resistor R2. The first output end of the driver chip U1 is connected to the first end of the primary coil of the transformer T1 through the capacitor C4, and the second output end of the driver chip U1 is connected to the second end of the primary coil of the transformer T1 through the resistor R5. The first input end of the driver chip U1 is connected to the ground GND1 through the resistor R3 and the capacitor C1 respectively. The second input end of the driver chip U1 is connected to the ground GND1 through the resistor R4 and the capacitor C2 respectively. The first secondary coil of the transformer T1 is connected to the main power tube Q4 via the first switch tube driving unit, and the second secondary coil of the transformer T1 is connected to the main power tube Q2 via the first switch tube driving unit; the control end 1 of the main power tube Q4 receives the first power tube driving signal DRV_H1 via the first switch tube driving unit; the control end 1 of the main power tube Q2 receives the second power tube driving signal DRV_H1 via the second switch tube driving unit. The third end 3 of the main power tube Q2 is simultaneously connected to the second end 2 of the main power tube Q4 and the ground GND1. The third end 3 of the main power tube Q2 is connected to the voltage VDD1, and the third end of the main power tube Q4 is connected to the ground GND2.

[0039] Combination Figure 3 It can be seen that the non-inverting input terminal of the comparator U108-B is connected to the control terminal 1 of the main power tube Q4 through the resistor R18 to receive the first power tube drive signal DRV_H1 or connected to the control terminal 1 of the main power tube Q2 to receive the second power tube drive signal DRV_H1, and generates a first comparison signal DRV_H11 or a second comparison signal DRV_H11 respectively. The input terminal of the digital isolator U2 is connected to the output terminal of the comparator U108-B to receive the first comparison signal DRV_H11 or the second comparison signal DRV_H11; the output terminal of the digital isolator U2 outputs the first isolation comparison signal DRV_H11 or the second isolation comparison signal DRV_H11. The DSP controller 300 is used to cut off the DSP driving signal DRV_H and the DSP driving signal DRV_L when the first isolation comparison signal DRV_H11 and the DSP driving signal DRV_H are different, or cut off the DSP driving signal DRV_H and the DSP driving signal DRV_L when the second isolation comparison signal DRV_H11 and the DSP driving signal DRV_L are different.

[0040] Further Figure 4 As shown, the first switch tube driving unit includes a switch tube Q3, a diode D1, a Zener diode DZ3, DZ5, resistors R7, R13, R14, R15, R16 and R17, and capacitors C10 and C11. The source of the switch tube Q3 is connected to the anode of the Zener diode DZ3, the cathode of the Zener diode DZ3 is connected to the opposite end of the first secondary coil of the transformer T1, the gate of the switch tube Q3 is connected to the cathode of the diode D3, the drain is connected to the cathode of the Zener diode DZ5 via the resistor R15, and the anode of the Zener diode DZ5 is connected to the control end of the power tube Q4. The anode of the diode D3 is connected to the opposite end of the first secondary coil of the transformer T1. The resistor R7 is connected between the same end and the opposite end of the first secondary coil of the transformer T1. One end of the resistor R13 is connected to the same end of the first secondary coil of the transformer T1, and the second end is connected to the cathode of the Zener diode DZ5. The resistor R16 is connected between the control terminal of the power tube Q4 and the ground GND2, the resistor R17 and the capacitor C11 are connected in series between the control terminal of the power tube Q4 and the ground GND2, and the capacitor C10 is connected between the cathode and the anode of the Zener diode DZ5.

[0041] The second switch tube driving unit includes a switch tube Q1, a diode D1, a Zener diode DZ2, DZ1, resistors R9, R6, R8, R10, R11 and R12, and capacitors C8 and C6. The source of the switch tube Q1 is connected to the anode of the Zener diode DZ2, the cathode of the Zener diode DZ2 is connected to the same-name end of the second secondary coil of the transformer T1, the gate of the switch tube Q1 is connected to the cathode of the diode D1, the drain is connected to the cathode of the Zener diode DZ1 through the resistor R10, and the anode of the Zener diode DZ1 is connected to the control end of the power tube Q2. The anode of the diode D1 is connected to the same-name end of the second secondary coil of the transformer T1. The first end of the resistor R6 is connected to the cathode of the Zener diode DZ2, and the second end is connected to the opposite-name end of the second secondary coil of the transformer T1 and the first end of the resistor R8. The second end of the resistor R8 is connected to the cathode of the Zener diode DZ1. The resistor R11 is connected between the control end of the power tube Q2 and the ground GND1, the resistor R12 and the capacitor C8 are connected in series between the control end of the power tube Q2 and the ground GND1. The capacitor C6 is connected between the cathode and the anode of the Zener diode DZ1.

[0042] The half-bridge circuit system of the utility model is adopted, and its switch tube drive protection circuit determines whether a drive abnormality occurs by comparing the power tube drive signal and the DSP drive signal. When a drive abnormality occurs, the DPS drive signal is turned off to prevent damage to the power tube. Moreover, its specific half-bridge circuit structure and the corresponding switch tube drive protection circuit can achieve more accurate control.

[0043] Although the present invention is described through specific embodiments, it should be understood by those skilled in the art that various changes and equivalent substitutions may be made to the present invention without departing from the scope of the present invention. In addition, various modifications may be made to the present invention for specific situations or materials without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed, but should include all implementation methods that fall within the scope of the claims of the present invention.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A switch tube driving protection circuit, characterized in that: include: A comparator module, used for generating a comparison signal based on any power tube drive signal of the bridge circuit and a reference voltage signal; An isolation module, used for isolating the comparison signal and then outputting an isolated comparison signal; The DSP controller is used to cut off the DSP driving signal when the isolation comparison signal and the DSP driving signal are different.

2. The switch tube driving protection circuit according to claim 1, characterized in that: The comparator module includes a comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; The non-phase input terminal of the comparator is connected to the control terminal of any power tube of the bridge circuit via the first resistor to receive the power tube drive signal, and is connected to the first working voltage via the second resistor; the inverting input terminal of the comparator is connected to the first working voltage via the third resistor, and is grounded via the fourth resistor; the positive voltage electrode of the comparator is connected to the first working voltage, and the negative voltage electrode is grounded; the fifth resistor is connected between the non-phase input terminal and the output terminal of the comparator; the output terminal of the comparator outputs the comparison signal.

3. The switch tube driving protection circuit according to claim 2, characterized in that: The isolation module includes a digital isolator and a sixth resistor; the first power supply terminal of the digital isolator is connected to the second working voltage, and the input terminal is connected to the output terminal of the comparator to receive the comparison signal; the sixth resistor is connected between the first power supply terminal of the digital isolator and the output terminal of the comparator; the output terminal of the digital isolator outputs the isolation comparison signal.

4. The switch tube driving protection circuit according to claim 3, characterized in that: The device further includes a seventh resistor connected between the output terminal of the comparator and the input terminal of the digital isolator.

5. A half-bridge circuit system, comprising a driver chip module, a transformer, a first switch tube driving unit, a second switch tube driving unit, a first main power tube and a second main power tube, characterized in that: Further including a switch tube drive protection circuit; The switch tube driving protection circuit comprises: A comparator module, used for generating a comparison signal based on a power tube drive signal of a half-bridge circuit and a reference voltage signal; An isolation module, used for isolating the comparison signal and then outputting an isolated comparison signal; The DSP controller is used to cut off the DSP driving signal when the isolation comparison signal and the DSP driving signal are different.

6. The half-bridge circuit system according to claim 5, characterized in that: The comparator module includes a comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; the non-phase input terminal of the comparator is connected to the control terminal of any power tube of the half-bridge circuit via the first resistor to receive the power tube drive signal, and is connected to the first working voltage via the second resistor; the inverting input terminal of the comparator is connected to the first working voltage via the third resistor, and is grounded via the fourth resistor; the positive voltage electrode of the comparator is connected to the first working voltage, and the negative voltage electrode is grounded; the fifth resistor is connected between the non-phase input terminal and the output terminal of the comparator; the output terminal of the comparator outputs the comparison signal; The isolation module includes a digital isolator and a sixth resistor; the first power supply terminal of the digital isolator is connected to the second working voltage, and the input terminal is connected to the output terminal of the comparator to receive the comparison signal; the sixth resistor is connected between the first power supply terminal of the digital isolator and the output terminal of the comparator; the output terminal of the digital isolator outputs the isolation comparison signal.

7. The half-bridge circuit system according to claim 6, characterized in that: The driving chip module includes a driving chip, an eighth resistor, a ninth resistor, a first capacitor and a tenth resistor. The first input end of the driving chip receives a first DSP driving signal via the eighth resistor, and the second input end of the driving chip receives a second DSP driving signal via the ninth resistor. The first output end of the driving chip is connected to the first end of the primary coil of the transformer via the first capacitor, and the second output end of the driving chip is connected to the second end of the primary coil of the transformer via the tenth resistor; the first secondary coil of the transformer is connected to the first main power tube via the first switch tube driving unit, and the second secondary coil of the transformer is connected to the second main power tube via the first switch tube driving unit; the control end of the first main power tube receives the first power tube driving signal via the first switch tube driving unit; and the control end of the second main power tube receives the second power tube driving signal via the second switch tube driving unit.

8. The half-bridge circuit system according to claim 7, characterized in that: The non-inverting input terminal of the comparator is connected to the control terminal of the first main power tube via the first resistor to receive the first power tube driving signal or connected to the control terminal of the second main power tube to receive the second power tube driving signal, and generates a first comparison signal or a second comparison signal respectively.

9. The half-bridge circuit system according to claim 8, characterized in that: The input end of the digital isolator is connected to the output end of the comparator to receive the first comparison signal or the second comparison signal; the output end of the digital isolator outputs the first isolation comparison signal or the second isolation comparison signal.

10. The half-bridge circuit system according to claim 9, characterized in that: The DSP controller is used to cut off the first DSP driving signal and the second DSP driving signal when the first isolation comparison signal and the first DSP driving signal are different, or cut off the first DSP driving signal and the second DSP driving signal when the second isolation comparison signal and the second DSP driving signal are different.

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