Switch driving circuit of power device, switch module and electronic equipment

Abstract

The invention discloses a switch driving circuit of a power device, a switch module and electronic equipment, and belongs to the technical field of electronic equipment. In the switch driving circuit of the power device, a switch unit is respectively connected with a driving control end, a driving input end, a driving output end, a first grounding end and a second grounding end, and is used for connecting the driving input end and the driving output end under the control of a first control signal provided by the driving control end; under the control of a second control signal provided by the driving control end, the driving input end and the driving output end are disconnected, the driving output end and the first grounding end are connected, and the first grounding end and the second grounding end are disconnected, the driving input end is used for providing driving voltage for the power device, and the driving output end is used for being connected with the power device. The first grounding end is connected with the ground of a circuit where the power device is located, and the second grounding end is directly grounded. The switch driving circuit of the power device has high circuit stability.

Description

Technical Field

[0001] The present application belongs to the technical field of electronic equipment, and specifically relates to a switch drive circuit of a power device, a switch module and an electronic device. Background Art

[0002] With the continuous improvement of the performance of electronic products, higher requirements are placed on the switching frequency of power devices in electronic products while ensuring the stability of the products. For example, in the circuit of the air conditioner outdoor unit controller, a higher control frequency can be used to drive the power device to have a faster switching speed, thereby reducing the size of the filter inductor and capacitor in the circuit to save space and reduce costs. In addition, the high-frequency switching of the power device can respond to load changes more quickly, thereby effectively improving the dynamic performance of the system.

[0003] Among them, the insulated gate bipolar transistor (IGBT) is an important power device, and its switching frequency can be increased to 60 kilohertz (KHZ). However, a higher switching speed will bring a larger current change rate or voltage change rate, resulting in poor circuit stability. Summary of the invention

[0004] A switch drive circuit for a power device, a switch module, and an electronic device provided in the embodiments of the present application can realize a switch drive circuit for a power device with higher circuit stability.

[0005] In a first aspect, a switch driving circuit of a power device is provided, wherein the switch driving circuit of the power device comprises: a driving control terminal, a driving input terminal, a driving output terminal, a first ground terminal, a second ground terminal and a switch unit;

[0006] The switch unit is connected to the drive control end, the drive input end, the drive output end, the first ground end and the second ground end respectively, and is used to connect the drive input end and the drive output end under the control of a first control signal provided by the drive control end; disconnect the drive input end and the drive output end, connect the drive output end and the first ground end, and disconnect the first ground end and the second ground end under the control of a second control signal provided by the drive control end.

[0007] Among them, the driving input end is used to provide a driving voltage for the power device, the driving output end is used to connect with the power device and output the driving voltage to the power device, the first grounding end is connected to the ground of the circuit where the power device is located, and the second grounding end is directly grounded.

[0008] Optionally, the switch unit comprises: a first switch module and a second switch module;

[0009] The first switch module is connected to the drive control end, the drive input end, the drive output end and the first node, and is used to connect the drive input end and the drive output end under the control of the first control signal; and disconnect the drive input end and the drive output end, and connect the drive output end and the first node under the control of the second control signal;

[0010] The second switch module is connected to the drive control end, the first ground end, the second ground end and the first node, and is used to connect the first node and the first ground end and disconnect the first node and the second ground end under the control of the second control signal. The first node is the connection intersection of the first switch module and the second switch module.

[0011] Optionally, the first switch module includes: a first switch tube and a second switch tube;

[0012] The control end of the first switch tube is connected to the driving control end, the input end of the first switch tube is connected to the driving input end, and the output end of the first switch tube is connected to the driving output end, and is used to be turned on under the control of the first control signal and turned off under the control of the second control signal;

[0013] The control end of the second switch tube is connected to the drive control end, the input end of the second switch tube is connected to the drive output end, and the output end of the second switch tube is connected to the first node, and is used to be turned off under the control of the first control signal and turned on under the control of the second control signal.

[0014] Optionally, the second switch module includes: a third switch tube and a fourth switch tube;

[0015] The control end of the third switch tube is connected to the driving control end, the input end of the third switch tube is connected to the first node, the output end of the third switch tube is connected to the second ground end, and the third switch tube is used to be turned off under the control of the second control signal;

[0016] The control end of the fourth switch tube is connected to the driving control end, the input end of the fourth switch tube is connected to the first node, and the output end of the fourth switch tube is connected to the first ground end, and is used to be turned on under the control of the second control signal.

[0017] Optionally, the fourth switch tube is a switch tube with a body diode; the third switch tube is used to be turned on under the control of the first control signal; and the fourth switch tube is used to be turned off under the control of the first control signal.

[0018] Optionally, the switch driving circuit of the power device further includes: an inverting unit, the inverting unit is used to convert the first control signal output by the driving control end into a second control signal, or convert the second control signal output by the driving control end into the first control signal; the first switch module includes: a first switch tube and a second switch tube;

[0019] The control end of the first switch tube is connected to the driving control end through the inverting unit, the input end of the first switch tube is connected to the driving input end, and the output end of the first switch tube is connected to the driving output end, and is used to be turned on under the control of a second control signal converted from a first control signal provided by the driving control end, and turned off under the control of a first control signal converted from a second control signal provided by the driving control end;

[0020] The control end of the second switch tube is connected to the driving control end, the input end of the second switch tube is connected to the driving output end, and the output end of the second switch tube is connected to the first node, and is used to be turned off under the control of a first control signal provided by the driving control end, and turned on under the control of a second control signal provided by the driving control end.

[0021] Optionally, the second switch module includes: a third switch tube and a fourth switch tube;

[0022] The control end of the third switch tube is connected to the driving control end through the inverting unit, the input end of the third switch tube is connected to the first node, the output end of the third switch tube is connected to the second ground end, and the third switch tube is used to be turned off under the control of the first control signal after the second control signal provided by the driving control end is converted;

[0023] The control end of the fourth switch tube is connected to the drive control end, the input end of the fourth switch tube is connected to the first node, and the output end of the fourth switch tube is connected to the first ground end, and is used to be turned on under the control of the second control signal provided by the drive control end.

[0024] Optionally, the switch driving circuit of the power device further includes: a comparator;

[0025] The comparator is connected to the drive control end and is used to filter the signal provided by the drive control end and retain the square wave signal within a preset range in the signal provided by the drive control end. The signal provided by the drive control end includes the first control signal and the second control signal.

[0026] Optionally, the switch driving circuit of the power device further includes: a logic chip;

[0027] The logic chip is connected to the driving input terminal, the second ground terminal and the comparator, and is used for performing voltage boost processing on the signal output by the comparator to obtain a boosted signal.

[0028] In a second aspect, a switch module is provided, wherein the boost module comprises: a power device, and a switch drive circuit of the power device connected to the power device, wherein the switch drive circuit is the switch drive circuit of the power device described in any one of the first aspects.

[0029] Optionally, the boost module includes a BOOST boost circuit, and the power device is an insulated gate bipolar transistor in the BOOST boost circuit.

[0030] In a third aspect, an electronic device is provided, wherein the electronic device comprises a switch drive circuit of a power device as described in any one of the first aspect, or the electronic device comprises a switch module as described in any one of the second aspect.

[0031] The switch drive circuit, switch module and electronic device of the power device provided in the embodiment of the present application, the switch drive circuit of the power device includes: a drive control terminal, a drive input terminal, a drive output terminal, a first ground terminal, a second ground terminal and a switch unit. Among them, the switch unit is used to connect the drive input terminal and the drive output terminal under the control of the first control signal provided by the drive control terminal; under the control of the second control signal provided by the drive control terminal, disconnect the drive input terminal and the drive output terminal, connect the drive output terminal and the first ground terminal, and disconnect the first ground terminal and the second ground terminal. In this technical solution, the switch unit can connect the drive input terminal and the drive output terminal under the control of the first control signal to transmit the drive voltage to the power device and control the power device to turn on. In addition, the switch unit can disconnect the drive input terminal and the drive output terminal under the control of the second control signal, and connect the drive output terminal and the first ground terminal, so that the voltage remaining after the power device is turned on can be introduced into the ground of the circuit where the power device is located through the drive output terminal and the first ground terminal. Moreover, because the switch unit disconnects the first ground terminal and the second ground terminal while connecting the drive output terminal and the first ground terminal. Therefore, the change in the ground potential of the circuit where the power device is located due to the received retained voltage of the power device cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit and improves the stability of the circuit. In addition, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the driving loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is one of the structural schematic diagrams of the switch driving circuit provided by the prior art;

[0033] Figure 2 This is the second structural schematic diagram of the switch driving circuit provided by the prior art;

[0034] Figure 3 This is the third structural schematic diagram of the switch driving circuit provided by the prior art;

[0035] Figure 4 This is one of the structural schematic diagrams of the switch driving circuit of the power device provided in the embodiment of the present application;

[0036] Figure 5 This is the second structural schematic diagram of the switch driving circuit of the power device provided in the embodiment of the present application;

[0037] Figure 6 This is the third structural schematic diagram of the switch driving circuit of the power device provided in the embodiment of the present application;

[0038] Figure 7 This is the fourth structural schematic diagram of the switch driving circuit of the power device provided in the embodiment of the present application;

[0039] Figure 8 This is the fifth structural schematic diagram of the switch driving circuit of the power device provided in the embodiment of the present application;

[0040] Fig. 9 This is one of the structural schematic diagrams of the switch module provided in the embodiment of the present application. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] With the continuous improvement of the performance of electronic products, higher requirements are placed on the switching frequency of power devices in electronic products while ensuring the stability of the products. For example, in the circuit of the air conditioner outdoor unit controller, a higher control frequency can be used to drive the power device to have a faster switching speed, thereby reducing the size of the filter inductor and capacitor in the circuit to save space and reduce costs. In addition, the high-frequency switching of the power device can respond to load changes more quickly, thereby effectively improving the dynamic performance of the system.

[0043] Among them, IGBT is an important power device, and its switching frequency can be increased to 60KHZ. However, a higher switching frequency will cause greater switching losses in the IGBT, and a higher switching speed will bring about a larger current change rate or voltage change rate, which will lead to a larger stray inductance in the circuit, which will have a greater impact on the parasitic inductance and parasitic capacitance in the circuit, resulting in poor circuit stability.

[0044] Specifically, Figure 1 As shown, the IGBT system includes a switch drive circuit 10 and an IGBT 20. The gate of the IGBT 20 is connected to the switch drive circuit 10, the collector of the IGBT 20 is connected to the power supply terminal, and the emitter of the IGBT 20 is grounded through the ground terminal GND2. The switch drive circuit 10 is used to provide a drive voltage for the gate of the IGBT 20, and the drive voltage is used to drive the IGBT 20 to turn on, so as to connect its collector and emitter.

[0045] The switch driving circuit 10 includes a comparator OP1, an integrated circuit chip (IC) OP2, an inverter G, a first metal oxide semiconductor field effect transistor (MOS) and a second MOS.

[0046] Wherein, the comparator OP1 is connected to the logic IC OP2. The gate of the first MOS tube Q1 is connected to the logic IC OP2 through the inverter G, the source of the first MOS tube Q1 is used to receive the driving voltage of 15V, and the drain of the first MOS tube Q1 is connected to the gate of the IGBT 20. The gate of the second MOS tube Q2 is connected to the logic IC OP2 through the inverter G, the source of the second MOS tube Q2 is connected to the gate of the IGBT20, and the drain of the second MOS tube Q2 is grounded through the ground terminal GND1. In addition, the ground terminal GND2 is also connected to the ground terminal GN1. The comparator OP1 is used to receive a pulse width modulation (PWM) signal and filter the PWM signal to retain the PWM signal within a preset range. The logic IC OP2 is used to receive the PWM signal output by the comparator OP1 and perform a voltage-boosting process on the PWM signal so that the PWM signal after the voltage-boosting process can effectively control the on and off of the first MOS tube Q1 and the second MOS tube Q2. It should be noted that the first MOS tube Q1 is a PMOS tube and the second MOS tube Q2 is a NOS tube. The first MOS transistor Q1 and the second MOS transistor Q2 are configured to be turned on one and turned off the other at the same time under the control of a control signal received at a gate.

[0047] When the switch driving circuit 10 controls the IGBT 20 to turn on, Figure 2 As shown, the PWM signal control transmitted to the first MOS tube Q1 and the second MOS tube Q2 by the comparator OP1 and the logic IC OP2 turns on the first MOS tube Q1 and the second MOS tube Q2. The 15V driving voltage is transmitted to the gate of the IGBT 20 through the first MOS tube Q1 to control the IGBT 20 to turn on. Then, the gate voltage of the IGBT 20 flows to the ground terminal GND2 through the emitter. Among them, part of the gate voltage flows to the ground through the ground terminal GND2, and the other part of the gate voltage is transmitted to the ground terminal GND1 through the connecting line between the ground terminal GND2 and the ground terminal GND1, and finally flows to the ground.

[0048] Similarly, when the switch driving circuit 10 controls the IGBT 20 to turn off, Figure 3As shown, the first MOS tube Q1 is turned off and the second MOS tube Q2 is turned on by the PWM signal control transmitted to the first MOS tube Q1 and the second MOS tube Q2 by the comparator OP1 and the logic IC OP2. The gate voltage remaining at the gate of the IGBT 20 after the IGBT 20 is turned on flows to the ground terminal GND1 through the second MOS tube Q2. Part of the gate voltage flows to the ground through the ground terminal GND1, and the other part of the gate voltage is transmitted to the ground terminal GND2 through the connection line between the ground terminal GND1 and the ground terminal GND2, and finally flows to the ground.

[0049] Obviously, in the process of the switch drive circuit 10 controlling the IGBT 20 to turn on and off, the drive loop of the entire circuit is long and easily disturbed, thereby affecting the stability of the circuit. In addition, the circuit set on the printed circuit board (PCB) will have stray inductance. Among them, the stray inductance L0 of the PCB satisfies: =μ0×μr×l / 2π[ln(2l / w+t)+0.5]. Among them, L0 represents stray inductance, the unit is Henry. μ0 represents the vacuum permeability, which is about 4π×10-7H / m. μr represents the relative permeability, and the relative permeability of PCB copper is about 1. l represents the trace length, the unit is meter. w represents the trace width of the PCB, the unit is meter. t represents the copper thickness, the unit is meter. In addition, the stray inductance L0 also satisfies: V=(di / dt)×L0, V is the potential change of the circuit, and di / dt is the current change rate. Therefore, in the case of high-frequency switching of IGBT, the current change rate is faster, making the stray inductance of the circuit larger.

[0050] In addition, the presence of stray inductance can cause the potential of the ground terminal to be unstable. In addition, electromagnetic interference, power ripple and noise in the circuit will also propagate through the ground wire, further affecting the stability of the ground potential. Since the ground on the IGBT side (power side) and the ground on the switch drive circuit (drive side) are connected together, and some logic components in the switch drive circuit (for example, comparators, logic ICs, etc.) need to use the ground potential as a reference voltage. Therefore, the instability of the ground potential can easily cause some logic components in the switch drive circuit to work abnormally, thereby causing the overall abnormal operation of the switch drive circuit, affecting the working stability of the IGBT, and even causing damage to the IGBT.

[0051] Please refer to Figure 4 , which shows a schematic diagram of the structure of a switch driving circuit of a power device provided in an embodiment of the present application. The switch driving circuit of the power device is used to drive the IGBT to turn on or off, which can solve the above-mentioned problems to a certain extent. Figure 4 As shown, the switch driving circuit 10 of the power device includes:

[0052] A driving control terminal C, a driving input terminal VIN, a driving output terminal VOUT, a first ground terminal VGND1 , a second ground terminal VGND2 and a switch unit 401 .

[0053] The switch unit 401 is connected to the driving control terminal C, the driving input terminal VIN, the driving output terminal VOUT, the first ground terminal VGND1 and the second ground terminal VGND2 respectively. The switch unit 401 is used to connect the driving input terminal VIN and the driving output terminal VOUT under the control of the first control signal provided by the driving control terminal C. The switch unit 401 is also used to disconnect the driving input terminal VIN and the driving output terminal VOUT, connect the driving output terminal VOUT and the first ground terminal VGND1, and disconnect the first ground terminal VGND1 and the second ground terminal VGND2 under the control of the second control signal provided by the driving control terminal C.

[0054] The driving input terminal VIN is used to provide a driving voltage for the power device 20, and the driving voltage is used to control the power device to turn on. The driving output terminal VOUT is used to connect to the power device 20 to output the driving voltage to the power device 20. The first ground terminal VGND1 is connected to the ground GND2 of the circuit where the power device 20 is located. The second ground terminal VGND2 is directly grounded.

[0055] It should be noted that the drawings of the embodiments of the present application are all illustrated by taking the power device 20 as an IGBT as an example. Of course, the power device 20 may also be a power tube such as a MOS tube, which is not limited in the embodiments of the present application. In the case where the power device 20 is an IGBT, in the circuit where the power device 20 is located, the emitter of the IGBT is usually grounded GND2, the collector of the IGBT is usually connected to the power supply terminal, and the drive output terminal VOUT is connected to the gate of the IGBT. The drive output terminal VOUT is configured to output a drive voltage to the gate of the IGBT, control the collector and emitter of the IGBT to be connected, so that the current connected to the collector passes through the emitter streamline ground.

[0056] In the embodiment of the present application, when the switch driving circuit 10 needs to control the power device 20 to turn on, the driving control terminal C can be connected to the first control signal. Under the control of the first control signal, the switch unit 401 connects the driving input terminal VIN and the driving output terminal VOUT. At this time, the driving voltage connected to the driving input terminal VIN can flow to the power device 20 through the switch unit 401 and the driving output terminal VOUT in sequence to control the power device 20 to turn on. After the power device 20 is turned on, the conduction path of the power device 20 is connected to the ground, and the current flowing in the conduction path can flow to the ground through the power device 20.

[0057] Since the ground of the circuit where the power device 20 is located can receive the circulating current. Therefore, the ground potential of the circuit where the power device 20 is located (i.e., the power side) will change. However, since the switch drive circuit 10 of the power device is grounded through the second ground terminal. And when the power device 20 is turned on, the switch unit 104 does not control the connection between the first ground terminal and the second ground terminal. Therefore, the change in the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch drive circuit 10 through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit 10, avoids the interference of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch drive circuit 10, and improves the stability of the circuit. In addition, compared to Figure 2 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to turn on, the driving loop of the circuit is relatively short. The shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has stronger anti-interference ability.

[0058] In the case where the switch driving circuit 10 needs to control the power device 20 to turn off, the driving control terminal C can be connected to the second control signal. Under the control of the second control signal, the switch unit 401 disconnects the driving input terminal VIN and the driving output terminal VOUT, connects the driving output terminal VOUT and the first ground terminal VGND1, and disconnects the first ground terminal VGND1 and the second ground terminal VGND2. At this time, the remaining voltage remaining in the power device 20 after the power device 20 is turned on can flow to the first ground terminal VGND1 through the driving output terminal VOUT and the switch unit 401 in sequence, and finally flows to the ground connected to the power device 20.

[0059] Similarly, since the ground of the circuit where the power device 20 is located can receive the retained voltage. Therefore, the ground potential of the circuit where the power device 20 is located will change. However, since the switch drive circuit 10 of the power device is grounded through the second ground terminal. And when the power device 20 is turned off, the switch unit 104 controls the first ground terminal and the second ground terminal to be disconnected. Therefore, the change in the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch drive circuit 10 through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit 10, avoids the ground potential of the circuit where the power device 20 is located, and interferes with the ground potential of the switch drive circuit 10, thereby improving the stability of the circuit. In addition, compared to Figure 3 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to be disconnected, the driving loop of the circuit is relatively short. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has a stronger anti-interference ability.

[0060] In an embodiment of the present application, the switch driving circuit of the power device includes: a driving control end, a driving input end, a driving output end, a first ground end, a second ground end and a switch unit. Among them, the switch unit is used to connect the driving input end and the driving output end under the control of the first control signal provided by the driving control end; under the control of the second control signal provided by the driving control end, disconnect the driving input end and the driving output end, connect the driving output end and the first ground end, and disconnect the first ground end and the second ground end. In this technical solution, the switch unit can connect the driving input end and the driving output end under the control of the first control signal to transmit the driving voltage to the power device and control the power device to turn on. In addition, the switch unit can disconnect the driving input end and the driving output end under the control of the second control signal, and connect the driving output end and the first ground end, so that the voltage remaining after the power device is turned on can be introduced into the ground of the circuit where the power device is located through the driving output end and the first ground end. Moreover, since the switch unit disconnects the first ground end and the second ground end while connecting the driving output end and the first ground end. Therefore, the ground potential of the circuit where the power device 20 is located changes due to the received retained voltage of the power device, which cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, effectively ensuring the stability of the ground potential of the switch drive circuit and improving the stability of the circuit. In addition, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the drive loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent.

[0061] Alternatively, if Figure 5 and Figure 6 As shown, the switch unit 401 may include: a first switch module 4011 and a second switch module 4022 .

[0062] The first switch module 4011 is connected to the driving control terminal C, the driving input terminal VIN, the driving output terminal VOUT and the first node O1. The first switch module 4011 is used to connect the driving input terminal VIN and the driving output terminal VOUT under the control of the first control signal. The first switch module 4011 is also used to disconnect the driving input terminal VIN and the driving output terminal VOUT under the control of the second control signal, and connect the driving output terminal VOUT and the first node O1. The first node O1 is the connection intersection of the first switch module 4011 and the second switch module 4012.

[0063] The second switch module 4012 is connected to the driving control terminal C, the first ground terminal VGND1, the second ground terminal VGND2 and the first node O1. The second switch module 4012 is used to connect the first node O1 and the first ground terminal VGND1 under the control of the second control signal, and disconnect the first node O1 and the second ground terminal VGND2. Optionally, the second switch module 4012 can be used to disconnect the first node O1 and the first ground terminal VGND1 under the control of the first control signal. And / or, the second switch module 4012 can be used to disconnect the first node O1 and the second ground terminal VGND2 under the control of the first control signal.

[0064] In the embodiment of the present application, when the switch driving circuit 10 needs to control the power device 20 to turn on, the driving control terminal C can be connected to the first control signal. The first switch module 4011 is controlled by the first control signal to connect the driving input terminal VIN and the driving output terminal VOUT. At this time, the driving voltage connected to the driving input terminal VIN can flow to the power device 20 through the switch unit 401 and the driving output terminal VOUT in sequence to control the power device 20 to turn on.

[0065] If the second switch module 4012 disconnects the first node O1 and the first ground terminal VGND1, and / or the first node O1 and the second ground terminal VGND2 under the control of the first control signal, the change of the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch driving circuit 10 through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch driving circuit 10, avoids the interference of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch driving circuit 10, and improves the stability of the circuit.

[0066] In the case where the switch drive circuit 10 needs to control the power device 20 to be disconnected, the drive control terminal C can be connected to the second control signal. Under the control of the second control signal, the first switch module 4011 disconnects the drive input terminal VIN and the drive output terminal VOUT, and connects the drive output terminal VOUT and the first node O1. Under the control of the second control signal, the second switch module 4012 connects the first node O1 and the first ground terminal VGND1. At this time, the retained voltage remaining in the power device 20 after the power device 20 is turned on can pass through the drive output terminal VOUT, the first node O1, and the first ground terminal VGND1 in sequence, and finally flow to the ground connected to the power device 20. Because the second switch module 4012 disconnects the first node O1 and the second ground terminal VGND2 when the power device 20 is turned off. Therefore, the change of the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch drive circuit 10 through the first ground terminal and the second ground terminal, which effectively guarantees the stability of the ground potential of the switch drive circuit 10 and improves the stability of the circuit.

[0067] In some embodiments of the present application, Figure 5 As shown, the first switch module 4011 includes: a first switch tube Q3 and a second switch tube Q4.

[0068] The control end of the first switch tube Q3 is connected to the driving control end C, the input end of the first switch tube Q3 is connected to the driving input end VIN, and the output end of the first switch tube Q3 is connected to the driving output end VOUT. The first switch tube Q3 is used to be turned on under the control of the first control signal and turned off under the control of the second control signal. That is, the first switch tube Q3 is used to connect the driving input end VIN and the driving output end VOUT under the control of the first control signal; and disconnect the driving input end VIN and the driving output end VOUT under the control of the second control signal.

[0069] The control end of the second switch tube Q4 is connected to the driving control end C, the input end of the second switch tube Q4 is connected to the driving output end VOUT, and the output end of the second switch tube Q4 is connected to the first node O1. The second switch tube Q4 is used to be turned off under the control of the first control signal and turned on under the control of the second control signal. That is, the second switch tube Q4 is used to disconnect the driving output end VOUT and the first node O1 under the control of the first control signal; and connect the driving output end VOUT and the first node O1 under the control of the second control signal.

[0070] In an optional case, the first switch tube Q3 and the second switch tube Q4 are different types of MOS tubes. That is, the first switch tube Q3 is a PMOS tube, and the second switch tube Q4 is an NMOS tube. Alternatively, the first switch tube Q3 is an NMOS tube, and the second switch tube Q4 is a PMOS tube.

[0071] In some embodiments of the present application, Figure 5 As shown, the second switch module 4012 may include: a third switch tube Q5 and a fourth switch tube Q6.

[0072] The control end of the third switch tube Q5 is connected to the driving control end C, the input end of the third switch tube Q5 is connected to the first node O1, and the output end of the third switch tube Q5 is connected to the second ground terminal VGND2. The third switch tube Q5 is used to be turned off under the control of the second control signal. Optionally, the third switch tube Q5 can also be used to be turned on under the control of the first control signal. That is, the third switch tube Q5 is used to connect the first node O1 and the second ground terminal VGND2 under the control of the first control signal; and disconnect the first node O1 and the second ground terminal VGND2 under the control of the second control signal.

[0073] The control end of the fourth switch tube Q6 is connected to the driving control end C, the input end of the fourth switch tube Q6 is connected to the first node O1, and the output end of the fourth switch tube Q6 is connected to the first ground terminal VGND1. The fourth switch tube Q6 is used to be turned on under the control of the second control signal. Optionally, in the case where the fourth switch tube Q6 is a switch tube with a body diode, the fourth switch tube Q6 is used to be turned off under the control of the first control signal. On this basis, the third switch tube Q3 can be used to be turned on under the control of the first control signal. That is, the fourth switch tube Q6 is used to disconnect the first node O1 and the first ground terminal VGND1 under the control of the first control signal; and connect the first node O1 and the first ground terminal VGND1 under the control of the second control signal.

[0074] In an optional case, the third switch tube Q5 and the fourth switch tube Q6 are MOS tubes of different types. The third switch tube Q5 and the first switch tube Q3 are MOS tubes of the same type. The fourth switch tube Q6 and the second switch tube Q4 are MOS tubes of the same type.

[0075] That is, in one case, the first switch tube Q3 is a PMOS tube, the second switch tube Q4 is an NMOS tube, the third switch tube Q5 is a PMOS tube, and the fourth switch tube Q6 is an NMOS tube. In this case, the first control signal can be a low level signal, and the second control signal can be a high level signal.

[0076] Alternatively, in another case, the first switch tube Q3 is an NMOS tube, the second switch tube Q4 is a PMOS tube, the third switch tube Q5 is an NMOS tube, and the fourth switch tube Q6 is a PMOS tube. In this case, the first control signal can be a high level signal, and the second control signal can be a low level signal.

[0077] It should be noted that, when the switch tube is an NMOS tube, the control end of the switch tube is the gate of the NMOS tube, the input end is the drain of the NMOS tube, and the output end is the source of the NMOS tube. When the switch tube is a PMOS tube, the control end of the switch tube is the gate of the PMOS tube, the input end is the source of the PMOS tube, and the output end is the drain of the PMOS. The switch tube here can be understood as a general term for the first switch tube Q3, the second switch tube Q4, the third switch tube Q5, and the fourth switch tube Q6.

[0078] In some embodiments, when the switch driving circuit 10 needs to control the power device 20 to turn on, the driving control terminal C is connected to the first control signal, the first switch tube Q3 is turned on, the second switch tube Q4 is turned off, the third switch tube Q5 is turned on, and the fourth switch tube Q6 is turned off.

[0079] At this time, the driving input terminal VIN is connected to the driving output terminal VOUT, the driving output terminal VOUT is disconnected from the first node O1, the first node O1 is connected to the second ground terminal VGND2, and the first node O1 is disconnected from the first ground terminal VGND1. The driving voltage connected to the driving input terminal VIN can flow to the power device 20 through the switch unit 401 and the driving output terminal VOUT in sequence to control the power device 20 to turn on.

[0080] Furthermore, the driving voltage received by the power device 20 can also flow through the power device 20 to the ground terminal GND2 of the circuit where the power device 20 is located. Among them, a part of the driving voltage flows to the ground of the circuit where the power device 20 is located through the ground terminal GND2, and the other part of the driving voltage is transmitted to the fourth transistor Q6 through the connecting line between the ground terminal GND2 and the first ground terminal VGND1. At this time, since the fourth transistor Q6 is in the off state. Therefore, the driving voltage usually cannot flow to the third transistor Q5 through the fourth transistor Q6, and then flow to the ground of the switch driving circuit 10 through the first ground terminal VGND1.

[0081] However, even if the body diode of the fourth transistor Q6 is turned on due to the ground potential of the circuit where the power device 20 is located being too high, the driving voltage can flow to the third transistor Q5 through the body diode of the fourth transistor Q6, and then flow to the ground of the switch drive circuit 10 through the first ground terminal VGND1. However, since the body diode has a clamping effect, both conduction and transmission will consume electrical energy. Therefore, the voltage flowing to the ground of the switch drive circuit 10 through the body diode of the fourth transistor Q6 will also be greatly reduced. Therefore, the change of the ground potential of the circuit where the power device 20 is located can also be reduced, and the influence on the ground potential of the switch drive circuit 10 can be improved to a certain extent. In addition, if the ground potential of the circuit where the power device 20 is located is a negative voltage, the body diode of the fourth transistor Q6 is in a reverse cut-off state, which can effectively avoid the influence of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch drive circuit 10, thereby ensuring the stability of the circuit.

[0082] Moreover, compared with Figure 2 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to turn on, the driving loop of the circuit is relatively short. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has a stronger anti-interference ability.

[0083] When the switch driving circuit 10 needs to control the power device 20 to be disconnected, the driving control terminal C receives the second control signal, the first switch tube Q3 is turned off, the second switch tube Q4 is turned on, the third switch tube Q5 is turned off, and the fourth switch tube Q6 is turned on.

[0084] At this time, the driving input terminal VIN and the driving output terminal VOUT are disconnected, the driving output terminal VOUT and the first node O1 are connected, the first node O1 and the second ground terminal VGND2 are disconnected, and the first node O1 and the first ground terminal VGND1 are connected. The remaining voltage remaining in the power device 20 after the power device 20 is turned on can flow to the first ground terminal VGND1 through the driving output terminal VOUT and the switch unit 401 in sequence, and finally flow to the ground connected to the power device 20.

[0085] However, since the switch driving circuit 10 is grounded through the second ground terminal VGND2, and the second ground terminal VGND2 is disconnected from the first node when the power device 20 is turned off, the change of the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch driving circuit 10 through the first node O1 and the second ground terminal VGND2, which effectively ensures the stability of the ground potential of the switch driving circuit 10, avoids the interference of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch driving circuit 10, and improves the stability of the circuit.

[0086] Moreover, even if the ground potential of the circuit where the power device 20 is located is very high, the body diode of the third switch tube Q5 is in a reverse cut-off state, which can effectively intercept the ground potential of the circuit where the power device 20 is located, and the influence on the ground potential of the switch drive circuit 10. Alternatively, even if the ground potential of the circuit where the power device 20 is located is low, causing the body diode of the third switch tube Q5 to be turned on, the retained voltage can pass through the fourth transistor Q6, flow through the body diode of the third transistor Q5, and then flow to the ground of the switch drive circuit 10 through the first ground terminal VGND1. However, since the body diode has a clamping effect, both conduction and transmission will consume electrical energy. Therefore, the voltage flowing to the ground of the switch drive circuit 10 through the body diode of the third transistor Q5 will also be greatly reduced. Therefore, the change of the ground potential of the circuit where the power device 20 is located can also be reduced, and the influence on the ground potential of the switch drive circuit 10 can be reduced, and the circuit stability can be improved to a certain extent.

[0087] Moreover, compared with Figure 3 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to be disconnected, the driving loop of the circuit is relatively short. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has a stronger anti-interference ability.

[0088] In some embodiments of the present application, Figure 6As shown, the switch drive circuit 10 of the power device also includes: an inverting unit 402. The inverting unit 402 is used to convert the first control signal output by the driving control terminal C into a second control signal, or convert the second control signal output by the driving control terminal C into the first control signal. Specifically, optionally, the first control signal is a high-level signal, and the second control signal is a low-level signal. The inverting unit 402 can convert the first control signal into a second control signal of a low-level signal, or convert the second control signal into a first control signal of a high-level signal. Alternatively, the first control signal is a low-level signal, and the second control signal is a high-level signal. The inverting unit 402 can convert the first control signal into a second control signal of a high-level signal, or convert the second control signal into the first control signal of a low-level signal.

[0089] Based on this, the first switch module 4011 includes: a first switch tube Q3 and a second switch tube Q4.

[0090] The control end of the first switch tube Q3 is connected to the driving control end C through the inverting unit 402, the input end of the first switch tube Q3 is connected to the driving input end VIN, and the output end of the first switch tube Q3 is connected to the driving output end VOUT. The first switch tube Q3 is used to be turned on under the control of the second control signal after the first control signal provided by the driving control end is converted, and turned off under the control of the first control signal after the second control signal provided by the driving control end is converted. That is, the first switch tube Q3 is used to connect the driving input end VIN and the driving output end VOUT under the control of the second control signal; and disconnect the driving input end VIN and the driving output end VOUT under the control of the first control signal.

[0091] The control end of the second switch tube Q4 is connected to the driving control end C, the input end of the second switch tube Q4 is connected to the driving output end VOUT, and the output end of the second switch tube Q4 is connected to the first node O1. The second switch tube Q4 is used to be turned off under the control of the first control signal and turned on under the control of the second control signal. That is, the second switch tube Q4 is used to disconnect the driving output end VOUT and the first node O1 under the control of the first control signal; and connect the driving output end VOUT and the first node O1 under the control of the second control signal.

[0092] In an optional case, the first switch tube Q3 and the second switch tube Q4 are MOS tubes of the same type. That is, the first switch tube Q3 and the second switch tube Q4 are both PMOS tubes. Alternatively, the first switch tube Q3 and the second switch tube Q4 are both NMOS tubes.

[0093] Further optionally, if Figure 6 As shown, the second switch module 4012 may include: a third switch tube Q5 and a fourth switch tube Q6.

[0094] The control end of the third switch tube Q5 is connected to the driving control end C through the inverting unit 402, the input end of the third switch tube Q5 is connected to the first node O1, and the output end of the third switch tube Q5 is connected to the second ground end VGND2. The third switch tube Q5 is used to be turned off under the control of the first control signal after the second control signal provided by the driving control end C is converted. Optionally, the third switch tube Q5 can also be used to be turned on under the control of the second control signal after the first control signal provided by the driving control end C is converted. That is, the third switch tube Q5 is used to disconnect the first node O1 and the second ground end VGND2 under the control of the first control signal; and connect the first node O1 and the second ground end VGND2 under the control of the second control signal.

[0095] The control end of the fourth switch tube Q6 is connected to the driving control end C, the input end of the fourth switch tube Q6 is connected to the first node O1, and the output end of the fourth switch tube Q6 is connected to the first ground terminal VGND1. The fourth switch tube Q6 is used to be turned on under the control of the second control signal. Optionally, in the case where the fourth switch tube Q6 is a switch tube with a body diode, the fourth switch tube Q6 is used to be turned off under the control of the first control signal. On this basis, the third switch tube Q3 can be used to be turned on under the control of the first control signal. That is, the fourth switch tube Q6 is used to disconnect the first node O1 and the first ground terminal VGND1 under the control of the first control signal; and connect the first node O1 and the first ground terminal VGND1 under the control of the second control signal.

[0096] In an optional case, the third switch tube Q5 and the fourth switch tube Q6 are MOS tubes of the same type. Further, the first switch tube Q3, the second switch tube Q4, the third switch tube Q5 and the fourth switch tube Q6 are MOS tubes of the same type.

[0097] That is, in one case, the first switch tube Q3, the second switch tube Q4, the third switch tube Q5 and the fourth switch tube Q6 are all PMOS tubes. In this case, the first control signal can be a low level signal, and the second control signal can be a high level signal.

[0098] Alternatively, in another case, the first switch tube Q3, the second switch tube Q4, the third switch tube Q5 and the fourth switch tube Q6 are all NMOS tubes. In this case, the first control signal may be a high level signal, and the second control signal may be a low level signal.

[0099] In some embodiments, when the switch driving circuit 10 needs to control the power device 20 to turn on, such as Figure 7 As shown, the driving control terminal C receives the first control signal, and the inverting unit 402 outputs the second control signal. The first switch tube Q3 is turned on, the second switch tube Q4 is turned off, the third switch tube Q5 is turned on, and the fourth switch tube Q6 is turned off.

[0100] At this time, the driving input terminal VIN is connected to the driving output terminal VOUT, the driving output terminal VOUT is disconnected from the first node O1, the first node O1 is connected to the second ground terminal VGND2, and the first node O1 is disconnected from the first ground terminal VGND1. The driving voltage connected to the driving input terminal VIN can flow to the power device 20 through the switch unit 401 and the driving output terminal VOUT in sequence to control the power device 20 to turn on.

[0101] Furthermore, the driving voltage received by the power device 20 can also flow through the power device 20 to the ground terminal GND2 of the circuit where the power device 20 is located. Among them, a part of the driving voltage flows to the ground of the circuit where the power device 20 is located through the ground terminal GND2, and the other part of the driving voltage is transmitted to the fourth transistor Q6 through the connecting line between the ground terminal GND2 and the first ground terminal VGND1. At this time, since the fourth transistor Q6 is in the off state. Therefore, the driving voltage usually cannot flow to the third transistor Q5 through the fourth transistor Q6, and then flow to the ground of the switch driving circuit 10 through the first ground terminal VGND1.

[0102] However, even if the body diode of the fourth transistor Q6 is turned on due to the ground potential of the circuit where the power device 20 is located being too high, the driving voltage can flow to the third transistor Q5 through the body diode of the fourth transistor Q6, and then flow to the ground of the switch drive circuit 10 through the first ground terminal VGND1. However, since the body diode has a clamping effect, both conduction and transmission will consume electrical energy. Therefore, the voltage flowing to the ground of the switch drive circuit 10 through the body diode of the fourth transistor Q6 will also be greatly reduced. Therefore, the change of the ground potential of the circuit where the power device 20 is located can also be reduced, and the influence on the ground potential of the switch drive circuit 10 can be improved to a certain extent. In addition, if the ground potential of the circuit where the power device 20 is located is a negative voltage, the body diode of the fourth transistor Q6 is in a reverse cut-off state, which can effectively avoid the influence of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch drive circuit 10, thereby ensuring the stability of the circuit.

[0103] Moreover, compared with Figure 2 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to turn on, the driving loop of the circuit is relatively short. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has a stronger anti-interference ability. Figure 7 The loop in the circuit is marked by a solid arrow line, and the arrow points to the direction of flow within the loop.

[0104] When the switch driving circuit 10 needs to control the power device 20 to be disconnected, such as Figure 8As shown, the driving control terminal C receives the second control signal, and the inverting unit 402 outputs the first control signal. The first switch tube Q3 is turned off, the second switch tube Q4 is turned on, the third switch tube Q5 is turned off, and the fourth switch tube Q6 is turned on.

[0105] At this time, the driving input terminal VIN and the driving output terminal VOUT are disconnected, the driving output terminal VOUT and the first node O1 are connected, the first node O1 and the second ground terminal VGND2 are disconnected, and the first node O1 and the first ground terminal VGND1 are connected. The remaining voltage remaining in the power device 20 after the power device 20 is turned on can flow to the first ground terminal VGND1 through the driving output terminal VOUT and the switch unit 401 in sequence, and finally flow to the ground connected to the power device 20.

[0106] However, since the switch driving circuit 10 is grounded through the second ground terminal VGND2, and the second ground terminal VGND2 is disconnected from the first node when the power device 20 is turned off, the change of the ground potential of the circuit where the power device 20 is located cannot affect the ground potential of the switch driving circuit 10 through the first node O1 and the second ground terminal VGND2, which effectively ensures the stability of the ground potential of the switch driving circuit 10, avoids the interference of the ground potential of the circuit where the power device 20 is located on the ground potential of the switch driving circuit 10, and improves the stability of the circuit.

[0107] Moreover, even if the ground potential of the circuit where the power device 20 is located is very high, the body diode of the third switch tube Q5 is in a reverse cut-off state, which can effectively intercept the ground potential of the circuit where the power device 20 is located, and the influence on the ground potential of the switch drive circuit 10. Alternatively, even if the ground potential of the circuit where the power device 20 is located is low, causing the body diode of the third switch tube Q5 to be turned on, the retained voltage can pass through the fourth transistor Q6, flow through the body diode of the third transistor Q5, and then flow to the ground of the switch drive circuit 10 through the first ground terminal VGND1. However, since the body diode has a clamping effect, both conduction and transmission will consume electrical energy. Therefore, the voltage flowing to the ground of the switch drive circuit 10 through the body diode of the third transistor Q5 will also be greatly reduced. Therefore, the change of the ground potential of the circuit where the power device 20 is located can also be reduced, and the influence on the ground potential of the switch drive circuit 10 can be reduced, and the circuit stability can be improved to a certain extent.

[0108] Moreover, compared with Figure 3 When the switch driving circuit 10 provided in the embodiment of the present application controls the power device 20 to be disconnected, the driving loop of the circuit is relatively short. Therefore, the switch driving circuit 10 provided in the embodiment of the present application also has a stronger anti-interference ability. Figure 8 The loop in the circuit is marked by a solid arrow line, and the arrow points to the direction of flow within the loop.

[0109] In some embodiments of the present application, Figures 5 to 8 As shown, the switch drive circuit 10 of the power device may also include: a comparator 403. The comparator 403 is connected to the drive control terminal C. The comparator 403 is used to filter the signal provided by the drive control terminal C, and retain the signal within a preset range in the signal provided by the drive control terminal C. The signal provided by the drive control terminal C includes a first control signal and a second control signal. The comparator 403 is also connected to the drive input terminal VIN and the second ground terminal VGND. In an optional implementation, the signal provided by the drive control terminal C is composed of a first control signal and a second control signal alternately. For example, the signal provided by the drive control terminal C is a PWM signal, the first control signal is a high-level signal in the PWM signal, and the second control signal is a low-level signal in the PWM signal. Alternatively, the first control signal is a low-level signal in the PWM signal, and the second control signal is a high-level signal in the PWM signal.

[0110] Further optionally, if Figures 5 to 8 As shown, the switch drive circuit 10 of the power device may also include: a logic IC 404. The logic IC 404 is connected to the drive input terminal VIN, the second ground terminal VGND and the comparator 403. The logic IC 404 is used to boost the signal output by the comparator to obtain a boosted signal. The boosted signal includes a first control signal and a second control signal. In an optional implementation, the signal provided by the drive control terminal C is alternately composed of the first control signal and the second control signal. For example, the signal provided by the drive control terminal C is a PWM signal. The comparator 403 is used to filter the PWM signal to obtain a filtered PWM signal, and output the filtered PWM signal to the logic IC 404. The logic IC 404 is used to boost the filtered PWM signal to obtain a boosted PWM signal. The boosted PWM signal can effectively control the first switch tube Q3, the second switch tube Q4, the third switch tube Q5 and the fourth switch tube Q6 to turn on or off.

[0111] In an embodiment of the present application, the switch unit can connect the drive input terminal and the drive output terminal under the control of the first control signal to transmit the drive voltage to the power device and control the power device to turn on. In addition, the switch unit can disconnect the drive input terminal and the drive output terminal under the control of the second control signal, and connect the drive output terminal and the first ground terminal, so that the voltage retained by the power device after turning on can be introduced into the ground of the circuit where the power device is located through the drive output terminal and the first ground terminal. In addition, since the switch unit disconnects the first ground terminal and the second ground terminal while connecting the drive output terminal and the first ground terminal. Therefore, the change in the ground potential of the circuit where the power device is located due to the received retained voltage of the power device cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, effectively ensuring the stability of the ground potential of the switch drive circuit and improving the stability of the circuit. In addition, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the drive loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent.

[0112] The following Fig. 9 The switch driving circuit shown in the figure further illustrates the switch driving circuit provided in the embodiment of the present application. Assume that the first switch tube Q3, the second switch tube Q4, the third switch tube Q5 and the fourth switch tube Q6 are all PMOS tubes, and the power device 20 is an IGBT. Accordingly, the first control signal is a low level signal, and the second control signal is a high level signal.

[0113] The driving control terminal C is connected to the logic IC 404 through the comparator 403. The gate of the first switch tube Q3 is connected to the logic IC 404 through the inverting unit 402, the source is connected to the driving input terminal VIN, the drain is connected to the second node O2, and the second node O2 is also connected to the driving output terminal VOUT.

[0114] The gate of the second switch tube Q4 is directly connected to the logic IC 404, the source is connected to the second node O2, and the drain is connected to the first node O1. The gate of the third switch tube Q5 is connected to the logic IC 404 through the inverting unit 402, the source is connected to the first node O1, and the drain is connected to the second ground terminal VGND2. The gate of the fourth switch tube Q6 is directly connected to the logic IC 404, the source is connected to the second node O2, and the drain is connected to the first ground terminal VGND1. The first ground terminal VGND1 is grounded through the ground terminal GND2 of the circuit where the power device 20 is located. The second ground terminal VGND2 is grounded through the ground terminal GND1 of the switch driving circuit 10.

[0115] The driving output terminal VOUT is connected to the gate of the IGBT 20. The collector of the IGBT 20 is connected to the power supply terminal VDD, and the emitter is connected to the ground terminal GND2. In addition, there are two branches between the driving output terminal VOUT and the gate of the IGBT 20. In one branch, the driving output terminal VOUT is connected to the gate of the IGBT 20 through the first resistor R1. In the other branch, the driving output terminal VOUT is connected to the gate of the IGBT 20 through the first diode D1 and the second resistor R2 connected in parallel. In addition, the cathode of the first diode D1 is connected to the driving output terminal VOUT, and the anode is connected to the gate of the IGBT 20 through the second resistor R2.

[0116] The driving control terminal C of the switch driving circuit 10 is connected to the PWM signal. When a high-level signal in the PWM signal is connected, the inverting unit 402 outputs a low-level signal. The first switch tube Q3 is turned on, the second switch tube Q4 is turned off, the third switch tube Q5 is turned on, and the fourth switch tube Q6 is turned off. At this time, the driving voltage connected to the driving input terminal VIN can flow to the power device 20 through the switch unit 401 and the driving output terminal VOUT in sequence to control the power device 20 to turn on. When a low-level signal in the PWM signal is connected, the inverting unit 402 outputs a high-level signal. The first switch tube Q3 is turned off, the second switch tube Q4 is turned on, the third switch tube Q5 is turned off, and the fourth switch tube Q6 is turned on. At this time, the retained voltage remaining in the power device 20 after the power device 20 is turned on can flow to the first ground terminal VGND1 through the driving output terminal VOUT and the switch unit 401 in sequence, and finally flow to the ground connected to the power device 20.

[0117] In some embodiments, the power device 20 may be an IGBT in a boost circuit. Optionally, the boost circuit may be a BOOST boost circuit. For example, please continue to refer to Fig. 9 , which shows a schematic diagram of the structure of a switch module provided in an embodiment of the present application. Fig. 9As shown, the switch module includes a switch drive circuit 10 provided in an embodiment of the present application, and a BOOST boost circuit 2. The BOOST boost circuit 2 includes a second diode D2, an inductor L and a capacitor C. The power supply terminal VDD is connected to the current input terminal of the inductor L, and the current output terminal of the inductor L is respectively connected to the collector of the IGBT 20, and is also connected to the anode of the second diode D2. The cathode of the second diode D2 is respectively connected to the boost output terminal V_OUT_H and one end of the capacitor C, and the other end of the capacitor C is grounded through the ground terminal GND2. The BOOST boost circuit is used to convert the input DC voltage provided by the power supply terminal VDD into a DC voltage with a higher voltage and output the converted DC voltage through the boost output terminal V_OUT_H. In the BOOST boost circuit, the boost requirements of different application scenarios can be met by adjusting key parameters (such as duty cycle, inductance value of the inductor, capacitance value of the capacitor and switching frequency of the IGBT 20, etc.).

[0118] In summary, the switch drive circuit of the power device provided in the embodiment of the present application includes: a drive control terminal, a drive input terminal, a drive output terminal, a first ground terminal, a second ground terminal and a switch unit. Among them, the switch unit is used to connect the drive input terminal and the drive output terminal under the control of the first control signal provided by the drive control terminal; under the control of the second control signal provided by the drive control terminal, disconnect the drive input terminal and the drive output terminal, connect the drive output terminal and the first ground terminal, and disconnect the first ground terminal and the second ground terminal. In this technical solution, the switch unit can connect the drive input terminal and the drive output terminal under the control of the first control signal to transmit the drive voltage to the power device and control the power device to turn on. In addition, the switch unit can disconnect the drive input terminal and the drive output terminal under the control of the second control signal, and connect the drive output terminal and the first ground terminal, so that the voltage remaining after the power device is turned on can be introduced into the ground of the circuit where the power device is located through the drive output terminal and the first ground terminal. Moreover, since the switch unit disconnects the first ground terminal and the second ground terminal while connecting the drive output terminal and the first ground terminal. Therefore, the change in the ground potential of the circuit where the power device is located due to the received retained voltage of the power device cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit and improves the stability of the circuit. In addition, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the driving loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent.

[0119] The embodiment of the present application also provides a switch module. The boost module includes: a power device 20, and a switch drive circuit 10 of the power device connected to the power device 20. The switch drive circuit 10 of the power device is the switch drive circuit of the power device provided in the embodiment of the present application.

[0120] Alternatively, if Fig. 9 As shown, the boost module includes a BOOST boost circuit 2. The power device is an IGBT in the BOOST boost circuit 2. It should be noted that the power device 20 can also be a power device in other circuits. For example, the power device 20 can also be a Buck-Boost boost circuit, Power devices in circuits such as circuits.

[0121] In summary, the switch module provided by the embodiment of the present application, the switch driving circuit of the power device thereof includes: a driving control end, a driving input end, a driving output end, a first ground end, a second ground end and a switching unit. Among them, the switching unit is used to connect the driving input end and the driving output end under the control of the first control signal provided by the driving control end; under the control of the second control signal provided by the driving control end, disconnect the driving input end and the driving output end, connect the driving output end and the first ground end, and disconnect the first ground end and the second ground end. In this technical solution, the switching unit can connect the driving input end and the driving output end under the control of the first control signal to transmit the driving voltage to the power device and control the power device to turn on. Moreover, the switching unit can disconnect the driving input end and the driving output end under the control of the second control signal, and connect the driving output end and the first ground end, so that the voltage remaining after the power device is turned on can be introduced into the ground of the circuit where the power device is located through the driving output end and the first ground end. Moreover, because the switch unit disconnects the first ground end and the second ground end while connecting the driving output end and the first ground end. Therefore, the change in the ground potential of the circuit where the power device is located due to the received retained voltage of the power device cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit and improves the stability of the circuit. In addition, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the driving loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent.

[0122] The embodiment of the present application also provides an electronic device, which may include a switch drive circuit of a power device provided in the embodiment of the present application. Alternatively, the electronic device may include a switch module provided in the embodiment of the present application. Thus, in the electronic device provided in the embodiment of the present application, the switch drive circuit includes: a drive control terminal, a drive input terminal, a drive output terminal, a first ground terminal, a second ground terminal and a switch unit. Among them, the switch unit is used to connect the drive input terminal and the drive output terminal under the control of the first control signal provided by the drive control terminal; disconnect the drive input terminal and the drive output terminal, connect the drive output terminal and the first ground terminal, and disconnect the first ground terminal and the second ground terminal under the control of the second control signal provided by the drive control terminal. In this technical solution, the switch unit can connect the drive input terminal and the drive output terminal under the control of the first control signal to transmit the drive voltage to the power device and control the power device to turn on. Moreover, the switch unit can disconnect the drive input terminal and the drive output terminal under the control of the second control signal, and connect the drive output terminal and the first ground terminal, so that the voltage remaining after the power device is turned on can be introduced into the ground of the circuit where the power device is located through the drive output terminal and the first ground terminal. Moreover, since the switch unit disconnects the first ground terminal and the second ground terminal while connecting the drive output terminal and the first ground terminal. Therefore, the change in the ground potential of the circuit where the power device is located due to the retention voltage of the power device cannot affect the ground potential of the switch drive circuit through the first ground terminal and the second ground terminal, which effectively ensures the stability of the ground potential of the switch drive circuit and improves the stability of the circuit. Moreover, when the switch drive circuit in the technical solution of the present application controls the power device to turn on or off, the drive loop of the circuit is relatively short, and the shorter the loop, the stronger the anti-interference ability of the circuit. Therefore, the switch drive circuit of the technical solution of the present application also has a strong anti-interference ability to a certain extent.

[0123] Optionally, the electronic device may further include a processor and a memory. The memory is used to store a computer program. The processor is used to implement the control method of the driver chip in the method embodiment of the present application when executing the program stored in the memory.

[0124] The embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the control method of the above-mentioned driver chip is implemented. Wherein, the processor is the processor in the electronic device in the above-mentioned embodiment. The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, etc.

[0125] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A switch driving circuit for a power device, characterized in that: The switch driving circuit of the power device comprises: a driving control terminal, a driving input terminal, a driving output terminal, a first ground terminal, a second ground terminal and a switch unit; The switch unit is connected to the drive control end, the drive input end, the drive output end, the first ground end and the second ground end respectively, and is used to connect the drive input end and the drive output end under the control of a first control signal provided by the drive control end; disconnect the drive input end and the drive output end, connect the drive output end and the first ground end, and disconnect the first ground end and the second ground end under the control of a second control signal provided by the drive control end. Among them, the driving input end is used to provide a driving voltage for the power device, the driving output end is used to connect with the power device and output the driving voltage to the power device, the first grounding end is connected to the ground of the circuit where the power device is located, and the second grounding end is directly grounded.

2. The switch driving circuit according to claim 1, characterized in that: The switch unit comprises: a first switch module and a second switch module; The first switch module is connected to the drive control end, the drive input end, the drive output end and the first node, and is used to connect the drive input end and the drive output end under the control of the first control signal; and disconnect the drive input end and the drive output end, and connect the drive output end and the first node under the control of the second control signal; The second switch module is connected to the drive control end, the first ground end, the second ground end and the first node, and is used to connect the first node and the first ground end and disconnect the first node and the second ground end under the control of the second control signal. The first node is the connection intersection of the first switch module and the second switch module.

3. The switch driving circuit according to claim 2, characterized in that: The first switch module includes: a first switch tube and a second switch tube; The control end of the first switch tube is connected to the driving control end, the input end of the first switch tube is connected to the driving input end, and the output end of the first switch tube is connected to the driving output end, and is used to be turned on under the control of the first control signal and turned off under the control of the second control signal; The control end of the second switch tube is connected to the drive control end, the input end of the second switch tube is connected to the drive output end, and the output end of the second switch tube is connected to the first node, and is used to be turned off under the control of the first control signal and turned on under the control of the second control signal.

4. The switch driving circuit according to claim 2 or 3, characterized in that: The second switch module includes: a third switch tube and a fourth switch tube; The control end of the third switch tube is connected to the driving control end, the input end of the third switch tube is connected to the first node, the output end of the third switch tube is connected to the second ground end, and the third switch tube is used to be turned off under the control of the second control signal; The control end of the fourth switch tube is connected to the driving control end, the input end of the fourth switch tube is connected to the first node, and the output end of the fourth switch tube is connected to the first ground end, and is used to be turned on under the control of the second control signal.

5. The switch driving circuit according to claim 4, characterized in that: The fourth switch tube is a switch tube with a body diode; the third switch tube is used to be turned on under the control of the first control signal; and the fourth switch tube is used to be turned off under the control of the first control signal.

6. The switch driving circuit according to claim 2, characterized in that: The switch driving circuit of the power device further includes: an inverting unit, the inverting unit is used to convert the first control signal output by the driving control end into a second control signal, or convert the second control signal output by the driving control end into the first control signal; the first switch module includes: a first switch tube and a second switch tube; The control end of the first switch tube is connected to the driving control end through the inverting unit, the input end of the first switch tube is connected to the driving input end, and the output end of the first switch tube is connected to the driving output end, and is used to be turned on under the control of a second control signal converted from a first control signal provided by the driving control end, and turned off under the control of a first control signal converted from a second control signal provided by the driving control end; The control end of the second switch tube is connected to the driving control end, the input end of the second switch tube is connected to the driving output end, and the output end of the second switch tube is connected to the first node, and is used to be turned off under the control of a first control signal provided by the driving control end, and turned on under the control of a second control signal provided by the driving control end.

7. The switch driving circuit according to claim 6, characterized in that: The second switch module includes: a third switch tube and a fourth switch tube; The control end of the third switch tube is connected to the driving control end through the inverting unit, the input end of the third switch tube is connected to the first node, the output end of the third switch tube is connected to the second ground end, and the third switch tube is used to be turned off under the control of the first control signal after the second control signal provided by the driving control end is converted; The control end of the fourth switch tube is connected to the drive control end, the input end of the fourth switch tube is connected to the first node, and the output end of the fourth switch tube is connected to the first ground end, and is used to be turned on under the control of the second control signal provided by the drive control end.

8. The switch driving circuit according to claim 1, characterized in that: The switch driving circuit of the power device further includes: a comparator; The comparator is connected to the drive control end and is used to filter the signal provided by the drive control end and retain the square wave signal within a preset range in the signal provided by the drive control end. The signal provided by the drive control end includes the first control signal and the second control signal.

9. The switch driving circuit according to claim 8, characterized in that: The switch driving circuit of the power device further includes: a logic chip; The logic chip is connected to the driving input terminal, the second ground terminal and the comparator, and is used to perform voltage boost processing on the signal output by the comparator to obtain a boosted signal.

10. A switch module, characterized in that: The boost module comprises: a power device, and a switch driving circuit of the power device according to any one of claims 1 to 9 connected to the power device.

11. The switch module according to claim 10, characterized in that: The boost module includes a BOOST boost circuit, and the power device is an insulated gate bipolar transistor in the BOOST boost circuit.

12. An electronic device, characterized in that: The electronic device comprises a switch drive circuit of a power device as described in any one of claims 1 to 9, or a switch module as described in claim 10 or 11.

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