Gate drive circuit and voltage converter

Abstract

The present application is applicable to the technical field of voltage converters, and provides a gate drive circuit and a voltage converter. The gate drive circuit includes a drive module, a start control module and a first switch module, the drive module is electrically connected to the start control module and the first switch module respectively, the start control module is electrically connected to the first switch module, the drive module, the start control module and the first switch module are all used to be electrically connected to the gate of the high-side switch tube, and the start control module and the first switch module are both used to be electrically connected to the source of the high-side switch tube. The gate drive circuit provided in the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss, and effectively reduce the risk of electromagnetic interference and overvoltage of the high-side switch tube.

Description

Technical Field

[0001] The present application belongs to the technical field of voltage converters, and in particular, relates to a gate drive circuit and a voltage converter. Background Art

[0002] In switching power supply circuits, MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is usually used as a switching tube. Since MOSFET has parasitic capacitance, resistance and inductance, it will cause switching losses. In addition, the switch tube will produce current and voltage overshoot and oscillation in the second and third stages of the switching process, thereby generating electromagnetic interference and having a negative impact on surrounding electronic equipment. If the voltage overshoot is large and exceeds the safe operating area of ​​the power device, the reliability of the chip will be reduced. The gate drive circuit directly determines the current and voltage overshoot and switching loss of the power device during the switching process. Traditional gate drive circuits usually need to be designed with a compromise between switching losses and electromagnetic interference. Summary of the invention

[0003] The embodiments of the present application provide a gate drive circuit and a voltage converter, which can solve the problem that the existing gate drive circuit usually needs to make a compromise design between switching loss and electromagnetic interference, thereby ensuring that the voltage overshoot is reduced while the switching loss remains unchanged.

[0004] In a first aspect, an embodiment of the present application provides a gate drive circuit, including a drive module, a start control module and a first switch module, wherein the drive module is electrically connected to the start control module and the first switch module respectively, the start control module is electrically connected to the first switch module, the drive module, the start control module and the first switch module are all used to be electrically connected to the gate of the high-side switch tube, and the start control module and the first switch module are both used to be electrically connected to the source of the high-side switch tube;

[0005] The driving module is used to output a driving voltage according to the first signal and the second signal;

[0006] When the high-side switch tube is in the first turn-on stage and the fourth turn-on stage, the turn-on control module is used to output a first control signal to the first switch module according to the driving voltage and the node voltage, and the node voltage is the voltage between the source of the high-side switch tube and the common end of the turn-on control module; the first switch module is used to be turned off according to the first control signal; when the high-side switch tube is in the second turn-on stage and the third turn-on stage, the turn-on control module is used to output a second control signal to the first switch module according to the driving voltage and the node voltage, and the first switch module is used to be turned on according to the second control signal.

[0007] In a possible implementation manner of the first aspect, the gate drive circuit further includes a shutdown control module and a second switch module, the shutdown control module is electrically connected to the drive module and the second switch module respectively, the shutdown control module and the second switch module are both used to be electrically connected to the gate of the high-side switch tube, and the shutdown control module and the second switch module are both used to be electrically connected to the source of the high-side switch tube;

[0008] When the high-side switch tube is in the first shutdown stage, the shutdown control module is used to control the driving voltage to decrease from the initial value to the first preset value according to the second signal; when the high-side switch tube is in the second shutdown stage and the third shutdown stage, the on-impedance of the shutdown control module increases, and the shutdown control module is used to control the driving voltage to decrease from the first preset value to the second preset value; when the high-side switch tube is in the fourth shutdown stage, the second switch module is used to turn on according to the driving voltage.

[0009] In a possible implementation of the first aspect, the driving module includes a first switch tube and a second switch tube, the source of the first switch tube is used to receive a first voltage, the gate of the first switch tube is used to receive the first signal, the drain of the first switch tube is electrically connected to the drain of the second switch tube, the start-up control module, the shutdown control module, the first switch module and the second switch module respectively, the gate of the second switch tube is electrically connected to the shutdown control module for receiving the second signal, and the source of the second switch tube is used to be electrically connected to the source of the high-side switch tube.

[0010] In a possible implementation manner of the first aspect, the start control module includes a logic unit, a regulating unit, and a signal output unit, the regulating unit is electrically connected to the logic unit and the signal output unit respectively, and the signal output unit is electrically connected to the first switch module;

[0011] The logic unit is used to output a first logic voltage signal to the adjustment unit according to the driving voltage and the node voltage, the adjustment unit is used to output an adjustment voltage to the signal output unit according to the first logic voltage signal and the driving voltage, and the signal output unit is used to output a control signal to the first switch module according to the adjustment voltage, the driving voltage and the node voltage, wherein the control signal includes the first control signal and the second control signal.

[0012] In a possible implementation of the first aspect, the logic unit includes a third switch tube, a fourth switch tube and a first resistor, the gate of the third switch tube and the gate of the fourth switch tube are both used to receive the driving voltage, the source of the third switch tube is used to receive the first voltage, the drain of the third switch tube is electrically connected to the drain of the fourth switch tube and the adjustment unit respectively, the source of the fourth switch tube is electrically connected to the first end of the first resistor, and the second end of the first resistor is used to be electrically connected to the source of the high-side switch tube.

[0013] In a possible implementation of the first aspect, the regulating unit includes a fifth switch tube, a second resistor and a first capacitor, the gate of the fifth switch tube is electrically connected to the logic unit, the source of the fifth switch tube is used to receive the driving voltage, the drain of the fifth switch tube is respectively electrically connected to the second end of the second resistor, the first end of the first capacitor and the signal output unit, the second end of the first capacitor is used to be electrically connected to the source of the high-side switch tube, and the first end of the second resistor is used to be electrically connected to the gate of the high-side switch tube.

[0014] In a possible implementation of the first aspect, the signal output unit includes a sixth switch tube and a seventh switch tube, the gate of the sixth switch tube and the gate of the seventh switch tube are both electrically connected to the adjustment unit, the source of the sixth switch tube is used to be electrically connected to the gate of the high-side switch tube, the drain of the sixth switch tube is respectively electrically connected to the drain of the seventh switch tube and the first switch module, and the source of the seventh switch tube is used to be electrically connected to the source of the high-side switch tube.

[0015] In a possible implementation of the first aspect, the first switch module includes an eighth switch tube, the gate of the eighth switch tube is electrically connected to the start-up control module, the drain of the eighth switch tube is used to be electrically connected to the gate of the high-side switch tube, and the source of the eighth switch tube is used to be electrically connected to the source of the high-side switch tube.

[0016] In a possible implementation manner of the first aspect, the shutdown control module includes a ninth switch tube and a first inverter, the gate of the ninth switch tube is electrically connected to the output end of the first inverter, the source of the ninth switch tube is used to be electrically connected to the gate of the high-side switch tube, the drain of the ninth switch tube is used to be electrically connected to the source of the high-side switch tube, and the input end of the first inverter is electrically connected to the driving module;

[0017] The second switch module includes a tenth switch tube and a second inverter, the input end of the second inverter and the drain of the tenth switch tube are both used to be electrically connected to the gate of the high-side switch tube, the output end of the second inverter is electrically connected to the gate of the tenth switch tube, and the source of the tenth switch tube is used to be electrically connected to the source of the high-side switch tube.

[0018] In a second aspect, an embodiment of the present application provides a voltage converter, comprising the gate drive circuit described in any one of the first aspects.

[0019] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0020] The gate drive circuit provided by the embodiment of the present application includes a drive module, a start control module and a first switch module. The drive module outputs a drive voltage according to a first signal and a second signal, which is used to drive the conduction and shutdown of the high-side switch tube. When the high-side switch tube is in the first start-up stage and the fourth start-up stage, the start control module outputs a first control signal to the first switch module according to the drive voltage and the node voltage, so that the first switch module is turned off according to the first control signal. In this way, the gate charging current of the high-side switch tube can be increased rapidly, and the gate charging voltage can be increased rapidly. When the high-side switch tube is in the second start-up stage and the third start-up stage, the start control module outputs a second control signal to the first switch module according to the drive voltage and the node voltage, so that the first switch module is turned on according to the second control signal. Thereby, a part of the gate charging current of the high-side switch tube is drawn away, the gate-source voltage of the high-side switch tube rises slowly, the drain-source voltage drop rate of the high-side switch tube is reduced, and then the jitter amplitude of the node voltage is reduced, which greatly reduces the voltage overshoot.

[0021] It can be seen from the above that when the high-side switch tube is in the second turn-on stage and the third turn-on stage, the embodiment of the present application controls the first switch module to be turned on by setting the turn-on control module, draws away a part of the gate charging current of the high-side switch tube, and slows down the rise of the gate-source voltage of the high-side switch tube, thereby greatly reducing the voltage overshoot. At the same time, when the high-side switch tube is in the first turn-on stage and the fourth turn-on stage, a larger gate drive current is used to avoid the switching loss caused by the increase in the switching time. Therefore, the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss by controlling the turn-on process of the high-side switch tube in stages, and effectively reduce the risk of electromagnetic interference and overvoltage of the high-side switch tube.

[0022] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 It is a structural schematic diagram of an existing synchronous buck circuit;

[0025] Figure 2 It is a schematic diagram of a parasitic model of a high-side switch tube in an existing synchronous buck circuit;

[0026] Figure 3 is a principle block diagram of a gate driving circuit provided in an embodiment of the present application;

[0027] Figure 4 is a principle block diagram of a gate driving circuit provided in another embodiment of the present application;

[0028] Figure 5 is a circuit connection diagram of a gate driving circuit provided in an embodiment of the present application;

[0029] Figure 6 is a circuit connection diagram of an existing gate drive circuit;

[0030] Figure 7 Schematic diagram of the working waveform of the gate driving circuit provided in one embodiment of the present application.

[0031] In the figure, 10, gate drive circuit; 101, drive module; 102, start control module; 1021, logic unit; 1022, adjustment unit; 1023, signal output unit; 103, first switch module; 104, shutdown control module; 105, second switch module. DETAILED DESCRIPTION

[0032] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0033] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0034] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0035] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0036] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0037] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0038] Since MOSFET has parasitic capacitance, resistance and inductance, it will cause switching loss. In addition, the switch tube will produce current and voltage overshoot and oscillation in the second and third stages of the switching process, thereby generating electromagnetic interference and having a negative impact on surrounding electronic equipment. If the voltage overshoot is large and exceeds the safe operating area of ​​the power device, the reliability of the chip will be reduced. The gate drive circuit directly determines the current and voltage overshoot and switching loss of the power device during the switching process. Traditional gate drive circuits usually need to be designed with a compromise between switching loss and electromagnetic interference.

[0039] Specifically, taking the synchronous buck circuit as an example, Figure 1 As shown, the control circuit is used to output corresponding control signals to the high-side drive circuit and the low-side drive circuit. The high-side drive circuit is used to output HS_Gate to the gate of the high-side switch tube M1 to drive the high-side switch tube M1. The low-side drive circuit is used to output LS_Gate to the gate of the lower switch tube M2 to drive the lower switch tube M2. Both M1 and M2 are NMOS tubes. A node LX is formed between the source of M1 and the drain of M2. A bootstrap capacitor C is provided between the node LX and the high-side drive circuit. BST , used to provide V for the high-side drive circuit BST Supply voltage. Figure 2 As shown, the PMOS tube Md1 and the NMOS tube Md2 together constitute a high-side driving circuit, which is used to output HS_Gate to the gate of the high-side switch tube M1 to drive the high-side switch tube M1. A gate resistor Rgate is connected in series at the gate of the high-side switch tube M1 to slow down the switching speed of the high-side switch tube M1 and reduce the voltage and current overshoot during the switching process. There is Cgd between the gate and the drain of the high-side switch tube M1, Cgs between the gate and the source of the high-side switch tube M1, and Cds between the drain and the source of the high-side switch tube M1.

[0040] The specific process of turning on the high-side switch tube M1 includes: the first stage: Md1 is turned on, V BSTCharge the gate of M1 and charge Cgs from 0V to the threshold voltage V th During this period, M1 is in the cut-off state, the drain current and drain voltage remain unchanged, and the inductor current I L All flows through the body diode of the lower switch tube M2, and the voltage of LX is -V d ; The second stage: the gate-source voltage of M1 reaches the threshold voltage V th , M1 is turned on, and the drain current is proportional to the gate voltage. At this time, the high-side switch tube M1 is in the linear working area (constant current area). During this period, the drain current increases, while the drain voltage remains unchanged; the third stage: M1 enters the Miller flat area, and the inductor current I L All flows through M1, and the VGS of M1 is I L / gm+V th and remain unchanged, the freewheeling diode of M2 is turned off, and the voltage of LX increases from -V d Increase to Vin-I L *Ron, VDS from Vin+V d Reduce to I L *Ron, Ron is the on-resistance of M1, the high-side drive circuit charges Cgd to achieve a rapid change in VDS voltage; Phase 4: The high-side drive circuit charges Cgd and Cgs, and VGS continues to increase until it reaches V BST . M1 enters the linear region, V BST The magnitude determines the on-resistance of M1.

[0041] The shutdown process of the high-side switch tube M1 also includes four stages. Since the shutdown process of M1 is the reverse process of the opening process, it will not be described in detail here. For specific working waveforms, please refer to Figure 7 The solid line waveform in . Among them, Figure 7 The working waveforms in the figure are, from top to bottom, the gate-source voltage VGS of the high-side switch tube, the drain-source current IDS of the high-side switch tube, the drain-source voltage VDS of the high-side switch tube, and the gate current IG of the high-side switch tube, and the horizontal axis is time t. The left column is a waveform diagram of the four stages of the high-side switch tube M1 turning on process, and the right column is a waveform diagram of the four stages of the high-side switch tube M1 turning off process.

[0042] As can be seen from the above, the changes in current and voltage mainly occur in the second and third stages. There are large voltage overshoots in both stages, which generate electromagnetic interference. Therefore, traditional gate drive circuits usually need to make a compromise between switching loss and electromagnetic interference.

[0043] Based on the above problems, the gate drive circuit provided by the embodiment of the present application includes a drive module, a start control module and a first switch module. The drive module outputs a drive voltage according to the first signal and the second signal, which is used to drive the conduction and shutdown of the high-side switch tube. When the high-side switch tube is in the first start-up stage and the fourth start-up stage, the start control module outputs a first control signal to the first switch module according to the drive voltage and the node voltage, so that the first switch module is turned off according to the first control signal. In this way, the gate charging current of the high-side switch tube can be increased rapidly, and the gate charging voltage can be increased rapidly. When the high-side switch tube is in the second start-up stage and the third start-up stage, the start control module outputs a second control signal to the first switch module according to the drive voltage and the node voltage, so that the first switch module is turned on according to the second control signal. Thereby, a part of the gate charging current of the high-side switch tube is drawn away, the gate-source voltage of the high-side switch tube rises slowly, the drain-source voltage drop rate of the high-side switch tube is reduced, and then the jitter amplitude of the node voltage is reduced, which greatly reduces the voltage overshoot.

[0044] It can be seen from the above that when the high-side switch tube is in the second turn-on stage and the third turn-on stage, the embodiment of the present application controls the first switch module to be turned on by setting the turn-on control module, draws away a part of the gate charging current of the high-side switch tube, and slows down the rise of the gate-source voltage of the high-side switch tube, thereby greatly reducing the voltage overshoot. At the same time, when the high-side switch tube is in the first turn-on stage and the fourth turn-on stage, a larger gate drive current is used to avoid the switching loss caused by the increase in the switching time. Therefore, the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss by controlling the turn-on process of the high-side switch tube in stages, and effectively reduce the risk of electromagnetic interference and overvoltage of the high-side switch tube.

[0045] In order to illustrate the technical solution described in this application, a specific embodiment is provided below for illustration.

[0046] Figure 3 FIG. 1 is a block diagram showing a gate drive circuit 10 according to an embodiment of the present application. Figure 3 As shown, the gate drive circuit 10 includes a drive module 101, a start control module 102 and a first switch module 103. The drive module 101 is electrically connected to the start control module 102 and the first switch module 103 respectively, and the start control module 102 is electrically connected to the first switch module 103. The drive module 101, the start control module 102, and the first switch module 103 are all used to be electrically connected to the gate of the high-side switch tube M1, and the start control module 102 and the first switch module 103 are all used to be electrically connected to the source of the high-side switch tube M1.

[0047] Specifically, the driving module 101 outputs a driving voltage HS_Gate according to the first signal and the second signal, which is used to drive the high-side switch tube M1 to be turned on and off. When the high-side switch tube M1 is in the first turn-on stage and the fourth turn-on stage, the start-up control module 102 outputs a first control signal to the first switch module 103 according to the driving voltage HS_Gate and the node voltage, so that the first switch module 103 is turned off according to the first control signal. In this way, the gate charging current of the high-side switch tube M1 can be increased rapidly, and the gate charging voltage can be increased rapidly. When the high-side switch tube M1 is in the second turn-on stage and the third turn-on stage, the start-up control module 102 outputs a second control signal to the first switch module 103 according to the driving voltage HS_Gate and the node voltage, so that the first switch module 103 is turned on according to the second control signal. Thereby, a part of the gate charging current of the high-side switch tube M1 is drawn away, the gate-source voltage VGS of the high-side switch tube M1 rises slowly, and the drain-source voltage VDS of the high-side switch tube M1 decreases, thereby reducing the jitter amplitude of the node voltage, greatly reducing the voltage overshoot.

[0048] It can be seen from the above that when the high-side switch tube M1 is in the second start-up stage and the third start-up stage, the embodiment of the present application controls the first switch module 103 to be turned on by setting the start-up control module 102, and draws away a part of the gate charging current of the high-side switch tube M1, so that the gate-source voltage VGS of the high-side switch tube M1 rises slowly, thereby greatly reducing the voltage overshoot. At the same time, when the high-side switch tube M1 is in the first start-up stage and the fourth start-up stage, a larger gate drive current is used to avoid the switching loss caused by the increase in the switching time. Therefore, the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss by controlling the start-up process of the high-side switch tube M1 in stages, and effectively reduce the electromagnetic interference and overvoltage risk of the high-side switch tube M1.

[0049] It should be noted that the first start-up stage is when the gate-source voltage VGS of the high-side switch tube M1 gradually increases to the threshold voltage V th The second start-up stage is when the gate-source voltage VGS of the high-side switch tube M1 is greater than or equal to the threshold voltage V th The third start-up stage is the stage in which the gate-source voltage VGS of the high-side switch tube M1 is equal to the first preset value and remains unchanged for a preset time. The fourth start-up stage is the stage in which the gate voltage of the high-side switch tube M1 gradually increases to the bootstrap voltage V BST stage.

[0050] Figure 4 FIG. 1 is a block diagram showing a gate drive circuit 10 according to another embodiment of the present invention. Figure 4As shown, the gate drive circuit 10 also includes a shutdown control module 104 and a second switch module 105. The shutdown control module 104 is electrically connected to the drive module 101 and the second switch module 105 respectively. The shutdown control module 104 and the second switch module 105 are both used to be electrically connected to the gate of the high-side switch tube M1. The shutdown control module 104 and the second switch module 105 are both used to be electrically connected to the source of the high-side switch tube M1.

[0051] Specifically, when the high-side switch tube M1 is in the first turn-off stage, the on-resistance of the turn-off control module 104 is the smallest, and the turn-off control module 104 can control the driving voltage HS_Gate to decrease from the initial value to the first preset value according to the second signal, so that the gate-source voltage VGS of the high-side switch tube M1 quickly drops to the second turn-off stage. When the high-side switch tube M1 is in the second turn-off stage and the third turn-off stage, the on-resistance of the turn-off control module 104 increases, so that the gate discharge current of the high-side switch tube M1 becomes smaller, the rate of decrease of the node voltage decreases, and the voltage overshoot is reduced. The driving voltage HS_Gate in this process continues to decrease to the second preset value. When the high-side switch tube M1 is in the fourth turn-off stage, the driving voltage HS_Gate has been reduced to the conduction threshold of the second switch module 105, so that the second switch module 105 is turned on, thereby increasing the gate discharge current of the high-side switch tube M1, and the gate-source voltage VGS of the high-side switch tube M1 can be quickly reduced to zero.

[0052] It can be seen from the above that when the high-side switch tube M1 is in the second turn-off stage and the third turn-off stage, the embodiment of the present application sets the turn-off control module 104 to control the driving voltage HS_Gate to gradually decrease, and the on-resistance of the turn-off control module 104 to gradually increase, thereby reducing the gate discharge current of the high-side switch tube M1, thereby reducing the voltage overshoot. At the same time, when the high-side switch tube M1 is in the first turn-off stage and the fourth turn-off stage, a discharge circuit with a smaller impedance is used to quickly discharge the gate current of the high-side switch tube M1, which can avoid the switching loss caused by the increase in switching time. Therefore, the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss by controlling the turn-off process of the high-side switch tube M1 in stages, and effectively reduce electromagnetic interference and overvoltage risks of the high-side switch tube M1.

[0053] It should be noted that the first off stage is when the gate voltage of the high-side switch tube M1 is bootstrapped by the voltage V BST The second off stage is the stage in which the gate-source voltage VGS of the high-side switch tube M1 is equal to the first preset value and remains unchanged for a preset time. The third off stage is the stage in which the gate-source voltage VGS of the high-side switch tube M1 is greater than or equal to the threshold voltage V thand is less than the first preset value, the fourth turn-off stage is when the gate-source voltage VGS of the high-side switch tube M1 is reduced from the threshold voltage V th gradually decreases to zero.

[0054] In summary, the gate drive circuit 10 provided in the embodiment of the present application can ensure that when the high-side switch tube M1 is in the second stage (the second turn-on stage and the second turn-off stage) and the third stage (the third turn-on stage and the third turn-off stage), a large voltage overshoot is avoided, which effectively reduces the risk of overvoltage of the high-side switch tube M1 and improves the reliability of the voltage converter. At the same time, when the high-side switch tube M1 is in the first stage (the first turn-on stage and the first turn-off stage) and the fourth stage (the fourth turn-on stage and the fourth turn-off stage), the switching loss caused by the increase in the switching time is avoided. Therefore, the embodiment of the present application can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss by controlling the turn-on and turn-off process of the high-side switch tube M1 in stages, and effectively reduce the electromagnetic interference and the risk of overvoltage of the high-side switch tube M1.

[0055] It should be noted that the present application achieves the purpose of reducing the overshoot of the drain-source voltage VDS of the high-side switch tube M1 by controlling and adjusting the driving voltage HS_Gate and the driving current. During the turning-on process of the high-side switch tube M1, the gate-source voltage VGS of the high-side switch tube M1 gradually increases from zero to V BST During the shutdown process of the high-side switch tube M1, the gate-source voltage VGS of the high-side switch tube M1 changes from V BST The difference between the node voltage and the initial value is V BST The first preset value is I L / gm+V th , the second preset value is the threshold voltage V th .

[0056] In one embodiment of the present application, Figure 5 As shown, the driving module 101 includes a first switch tube Q1 and a second switch tube Q2, the source of the first switch tube Q1 is used to receive a first voltage, the gate of the first switch tube Q1 is used to receive a first signal, the drain of the first switch tube Q1 is electrically connected to the drain of the second switch tube Q2, the start control module 102, the shutdown control module 104, the first switch module 103 and the second switch module 105 respectively, the gate of the second switch tube Q2 is electrically connected to the shutdown control module 104 for receiving the second signal, and the source of the second switch tube Q2 is electrically connected to the source of the high-side switch tube M1.

[0057] Specifically, the first switch tube Q1 and the second switch tube Q2 are both used as switch devices. The first switch tube Q1 can be turned on or off according to the first signal received by the gate, and the second switch tube Q2 can be turned on or off according to the second signal received by the gate. The first switch tube Q1 and the second switch tube Q2 work in coordination to output a driving voltage HS_Gate to the gate of the high-side switch tube M1 to drive the high-side switch tube M1.

[0058] For example, the designer can select the type of the first switch tube Q1 and the second switch tube Q2 according to the actual situation, that is, both can use fully controlled power devices such as metal oxide field effect transistors or insulated gate bipolar transistors. For example, the first switch tube Q1 can be selected as a PMOS tube, and the second switch tube Q2 can be selected as an NMOS tube.

[0059] In one embodiment of the present application, Figure 5 As shown, the start-up control module 102 includes a logic unit 1021, a regulating unit 1022 and a signal output unit 1023, the regulating unit 1022 is electrically connected to the logic unit 1021 and the signal output unit 1023 respectively, and the signal output unit 1023 is electrically connected to the first switch module 103. The logic unit 1021 is used to output a first logic voltage signal to the regulating unit 1022 according to the driving voltage HS_Gate and the node voltage, the regulating unit 1022 is used to output a regulating voltage to the signal output unit 1023 according to the first logic voltage signal and the driving voltage HS_Gate, and the signal output unit 1023 is used to output a control signal to the first switch module 103 according to the regulating voltage, the driving voltage HS_Gate and the node voltage, wherein the control signal includes a first control signal and a second control signal.

[0060] Specifically, when the high-side switch tube M1 is in the first turn-on stage and the fourth turn-on stage, the first control signal output by the signal output unit 1023 is a low-level signal, and the first switch module 103 is turned off. When the high-side switch tube M1 is in the second turn-on stage and the third turn-on stage, the second control signal output by the signal output unit 1023 is a high-level signal, and the first switch module 103 is turned on, which can draw away a portion of the gate charging current of the high-side switch tube M1, so that the gate-source voltage VGS of the high-side switch tube M1 rises slowly, thereby greatly reducing voltage overshoot.

[0061] In one embodiment of the present application, Figure 5As shown, the logic unit 1021 includes a third switch tube Q3, a fourth switch tube Q4 and a first resistor R1. The gate of the third switch tube Q3 and the gate of the fourth switch tube Q4 are both used to receive the driving voltage HS_Gate, the source of the third switch tube Q3 is used to receive the first voltage, the drain of the third switch tube Q3 is electrically connected to the drain of the fourth switch tube Q4 and the adjustment unit 1022 respectively, the source of the fourth switch tube Q4 is electrically connected to the first end of the first resistor R1, and the second end of the first resistor R1 is used to be electrically connected to the source of the high-side switch tube M1.

[0062] Specifically, the third switch tube Q3 and the fourth switch tube Q4 are both used as switch devices. The third switch tube Q3 can be driven by the drive voltage HS_Gate received by the gate and the drive voltage V received by the source. BST On or off, if the driving voltage HS_Gate is BST The difference between the gate voltage and the source voltage reaches the conduction threshold of the third switch tube Q3, and the third switch tube Q3 is turned on. The fourth switch tube Q4 can be turned on or off according to the driving voltage HS_Gate received by the gate and the voltage of the source. If the difference between the driving voltage HS_Gate and the source voltage reaches the conduction threshold of the fourth switch tube Q4, the fourth switch tube Q4 is turned on. The first resistor R1 is used as a current limiting resistor to limit the current flowing through the source of the fourth switch tube Q4 to prevent excessive current from damaging the fourth switch tube Q4. At the same time, the first resistor R1 is also used for impedance matching, which can match the impedance between the source of the fourth switch tube Q4 and the source of the high-side switch tube M1, and adjust the source voltage of the fourth switch tube Q4. The coordinated work of the third switch tube Q3, the fourth switch tube Q4 and the first resistor R1 can output a first logic voltage signal to the adjustment unit 1022.

[0063] For example, the designer can select the types of the third switch tube Q3 and the fourth switch tube Q4 according to the actual situation, that is, both can use fully controlled power devices such as metal oxide field effect transistors or insulated gate bipolar transistors. For example, the third switch tube Q3 can be selected as a PMOS tube, and the fourth switch tube Q4 can be selected as an NMOS tube.

[0064] In one embodiment of the present application, Figure 5 As shown, the regulating unit 1022 includes a fifth switch tube Q5, a second resistor R2 and a first capacitor C1, the gate of the fifth switch tube Q5 is electrically connected to the logic unit 1021, the source of the fifth switch tube Q5 is used to receive the driving voltage HS_Gate, the drain of the fifth switch tube Q5 is respectively electrically connected to the second end of the second resistor R2, the first end of the first capacitor C1 and the signal output unit 1023, the second end of the first capacitor C1 is used to be electrically connected to the source of the high-side switch tube M1, and the first end of the second resistor R2 is used to be electrically connected to the gate of the high-side switch tube M1.

[0065] Specifically, the fifth switch tube Q5 serves as a switching device, and the fifth switch tube Q5 can be turned on or off according to the first logic voltage signal and the driving voltage HS_Gate received by the gate. If the difference between the first logic voltage signal and the driving voltage HS_Gate reaches the turn-on threshold of the fifth switch tube Q5, the fifth switch tube Q5 is turned on. When the fifth switch tube Q5 is turned on, the driving module 101 can charge the first capacitor C1, and the first capacitor C1 stores energy. During this process, the voltage at point A gradually increases. When the fifth switch tube Q5 is turned off, the voltage at point A is equal to the node voltage. The second resistor R2 serves as a voltage regulating resistor, which is used to transmit the regulated voltage to the signal output unit 1023.

[0066] For example, the designer can select the type of the fifth switch tube Q5 according to the actual situation, that is, a fully controlled power device such as a metal oxide field effect transistor or an insulated gate bipolar transistor can be used. For example, the fifth switch tube Q5 can be selected as a PMOS tube.

[0067] In one embodiment of the present application, Figure 5 As shown, the signal output unit 1023 includes a sixth switch tube Q6 and a seventh switch tube Q7, the gate of the sixth switch tube Q6 and the gate of the seventh switch tube Q7 are both electrically connected to the adjustment unit 1022, the source of the sixth switch tube Q6 is used to be electrically connected to the gate of the high-side switch tube M1, the drain of the sixth switch tube Q6 is electrically connected to the drain of the seventh switch tube Q7 and the first switch module 103 respectively, and the source of the seventh switch tube Q7 is used to be electrically connected to the source of the high-side switch tube M1.

[0068] Specifically, the sixth switch tube Q6 and the seventh switch tube Q7 are both used as switch devices. The sixth switch tube Q6 can be turned on or off according to the first logic voltage signal received by the gate and the driving voltage HS_Gate received by the source. If the difference between the first logic voltage signal and the driving voltage HS_Gate reaches the turn-on threshold of the sixth switch tube Q6, the sixth switch tube Q6 is turned on. The seventh switch tube Q7 can be turned on or off according to the first logic voltage signal received by the gate and the node voltage. If the difference between the first logic voltage signal and the node voltage reaches the turn-on threshold of the seventh switch tube Q7, the seventh switch tube Q7 is turned on. The sixth switch tube Q6 and the seventh switch tube Q7 work in coordination to output a control signal to the first switch module 103. When the high-side switch tube M1 is in the first turn-on stage, since the voltage difference between the driving voltage HS_Gate and the node voltage is less than the threshold voltage of the high-side switch tube M1, the maximum value of the voltage at point B will also be less than the threshold voltage of the high-side switch tube M1, and the first switch module 103 is turned off. When the high-side switch tube M1 is in the second turn-on stage and the third turn-on stage, the sixth switch tube Q6 is turned on, the voltage at point B is pulled up, and the first switch module 103 is turned on, which can draw away a portion of the gate charging current of the high-side switch tube M1, so that the rise of the gate-source voltage VGS of the high-side switch tube M1 slows down, thereby greatly reducing the voltage overshoot. When the high-side switch tube M1 is in the fourth turn-on stage, due to the charging of the first capacitor C1, the voltage at point A is pulled up, the seventh switch tube Q7 is turned on, thereby lowering the voltage at point B, and the first switch module 103 is turned off.

[0069] For example, the designer can select the types of the sixth switch tube Q6 and the seventh switch tube Q7 according to the actual situation, that is, both can use fully controlled power devices such as metal oxide field effect transistors or insulated gate bipolar transistors. For example, the sixth switch tube Q6 can be selected as a PMOS tube, and the seventh switch tube Q7 can be selected as an NMOS tube.

[0070] In one embodiment of the present application, Figure 5 As shown, the first switch module 103 includes an eighth switch tube Q8, the gate of the eighth switch tube Q8 is electrically connected to the start-up control module 102, the drain of the eighth switch tube Q8 is used to be electrically connected to the gate of the high-side switch tube M1, and the source of the eighth switch tube Q8 is used to be electrically connected to the source of the high-side switch tube M1.

[0071] Specifically, the eighth switch tube Q8 serves as a switching device. The eighth switch tube Q8 can be turned on or off according to the control signal received by the gate. If the eighth switch tube Q8 receives the first control signal, the eighth switch tube Q8 is turned off. If the eighth switch tube Q8 receives the second control signal, the eighth switch tube Q8 is turned on.

[0072] For example, designers can select the type of the eighth switch tube Q8 according to actual conditions, that is, they can use fully controlled power devices such as metal oxide field effect transistors or insulated gate bipolar transistors. For example, the eighth switch tube Q8 can be selected as an NMOS tube.

[0073] In one embodiment of the present application, Figure 5 As shown, the shutdown control module 104 includes a ninth switch tube Q9 and a first inverter INV1, the gate of the ninth switch tube Q9 is electrically connected to the output end of the first inverter INV1, the source of the ninth switch tube Q9 is used to be electrically connected to the gate of the high-side switch tube M1, the drain of the ninth switch tube Q9 is used to be electrically connected to the source of the high-side switch tube M1, and the input end of the first inverter INV1 is electrically connected to the driving module 101.

[0074] Specifically, the first inverter INV1 is used to invert the received second signal and output a first inverted signal, that is, if the second signal is a high-level signal, the first inverter INV1 outputs a low-level signal, and if the second signal is a low-level signal, the first inverter INV1 outputs a high-level signal. The ninth switch tube Q9 is a switching device, and the ninth switch tube Q9 can be turned on or off according to the first inverted signal received by the gate. If the ninth switch tube Q9 receives a low-level signal, the ninth switch tube Q9 is turned on, and if the ninth switch tube Q9 receives a high-level signal, the ninth switch tube Q9 is turned off. Since the ninth switch tube Q9 is an NMOS tube, it is used to receive the second signal, and the ninth switch tube Q9 is a PMOS tube, it is used to receive the first inverted signal of the second signal. Therefore, when the second signal is a high-level signal, the second switch tube Q2 and the ninth switch tube Q9 are both turned on, which can provide a discharge path for the gate current of the high-side switch tube M1. When the high-side switch tube M1 is in the first off stage, the driving voltage HS_Gate is reduced from the initial value to the first preset value. The on-resistance of the ninth switch tube Q9 in this stage is the smallest, and the discharge path provided by the second switch tube Q2 and the ninth switch tube Q9 is a low-resistance discharge path. When the high-side switch tube M1 is in the second off stage and the third off stage, the driving voltage HS_Gate continues to decrease to the second preset value. As the driving voltage HS_Gate decreases, that is, as the source voltage of the ninth switch tube Q9 decreases, the on-resistance of the ninth switch tube Q9 increases, the gate discharge current of the high-side switch tube M1 decreases, the time of the third stage increases, the node voltage drop rate decreases, and the overshoot decreases.

[0075] In one embodiment of the present application, Figure 5As shown, the second switch module 105 includes a tenth switch tube Q10 and a second inverter INV2, the input end of the second inverter INV2 and the drain of the tenth switch tube Q10 are both used to be electrically connected to the gate of the high-side switch tube M1, the output end of the second inverter INV2 is electrically connected to the gate of the tenth switch tube Q10, and the source of the tenth switch tube Q10 is used to be electrically connected to the source of the high-side switch tube M1.

[0076] Specifically, the second inverter INV2 is used to invert the received signal of the driving voltage HS_Gate and output a second inverse signal. The tenth switch tube Q10 is a switching device. The tenth switch tube Q10 can be turned on or off according to the second inverse signal received by the gate. If the tenth switch tube Q10 receives a low-level signal, the tenth switch tube Q10 is turned off. If the tenth switch tube Q10 receives a high-level signal, the tenth switch tube Q10 is turned on. As the driving voltage HS_Gate continues to decrease, the tenth switch tube Q10 can be turned on, thereby adding a discharge path to the gate of the high-side switch tube M1, so that the decreasing rate of the driving voltage HS_Gate increases.

[0077] For example, the designer can select the type of the tenth switch tube Q10 according to the actual situation, that is, a fully controlled power device such as a metal oxide field effect transistor or an insulated gate bipolar transistor can be used. For example, the tenth switch tube Q10 can be selected as an NMOS tube.

[0078] Combine the following Figure 5 The circuit connection diagram shown and Figure 7 The working waveform diagram shown provides an overall description of the working process of the present application.

[0079] During the turn-on process of the high-side switch tube M1, in the first stage: the voltage difference between the driving voltage HS_Gate and the node voltage is less than the conduction threshold V of the high-side switch tube M1 th, so the maximum voltage at point B is also less than the turn-on threshold, the VGS of the ninth switch tube Q9 is less than the turn-on threshold, and has not reached the threshold voltage for turning on the ninth switch tube Q9. The ninth switch tube Q9 is turned off. At this stage, the voltage at point A is equal to the node voltage; the second stage: when the VGS of the high-side switch tube M1 reaches the turn-on threshold, the third switch tube Q3 is turned on, the fifth switch tube Q5 is turned off, and the sixth switch tube Q6 is turned on. At this time, the voltage at point B is equal to the driving voltage HS_Gate, that is, the voltage at point B is pulled up to reach the threshold voltage for turning on the ninth switch tube Q9. The ninth switch tube Q9 is turned on, thereby drawing away a part of the driving current of the gate of the high-side switch tube M1, and the VGS of the high-side switch tube M1 rises Slow down; the third stage: when the high-side switch tube M1 enters the Miller flat area, the VGS of the ninth switch tube Q9 increases and remains unchanged. At this time, the drain current of the high-side switch tube M1 reaches the maximum, the gate charging current of the high-side switch tube M1 further decreases, the VDS drop rate slows down, and the jitter amplitude of the node voltage becomes smaller. In this stage, the fourth switch tube Q4 starts to turn on, the fifth switch tube Q5 is turned on, the first capacitor C1 starts to charge, and the voltage at point A increases; the fourth stage: as the voltage at point A increases, the seventh switch tube Q7 is turned on, the voltage at point B decreases, and the ninth switch tube Q9 is turned off. The gate charging current of the high-side switch tube M1 increases, and the gate of the high-side switch tube M1 is quickly charged to V BST .

[0080] During the shutdown process of the high-side switch tube M1, in the first stage: the second switch tube Q2 is turned on, the eighth switch tube Q8 is turned on, and VGS is equal to V BST and the maximum voltage difference between the node voltage, in this stage, the on-resistance of the eighth switch tube Q8 is the smallest, the second switch tube Q2 and the eighth switch tube Q8 provide a low-resistance discharge path for the gate of the high-side switch tube M1, and the VGS of the high-side switch tube M1 quickly drops to the Miller flat region voltage; the second stage: as the driving voltage HS_Gate continues to decrease, the on-resistance of the eighth switch tube Q8 gradually increases, the gate discharge current of the high-side switch tube M1 becomes smaller, the time of the Miller flat region increases, the node voltage drop rate slows down, and the overshoot of the drain-source voltage VDS of the high-side switch tube M1 decreases; the third stage: the driving voltage HS_Gate decreases to below I L / gm+V th , but the Schmit flip voltage has not been triggered yet, the gate voltage of the high-side switch tube M1 is still discharged through the second switch tube Q2 and the eighth switch tube Q8. Due to the decrease in the driving voltage HS_Gate, the gate discharge capacity of the high-side switch tube M1 is weakened, and the drain current change rate slows down; the fourth stage: the driving voltage HS_Gate continues to decrease until the Schmit output voltage turns high (the power supply of the Schmit is V BST), the tenth switch tube Q10 is turned on, adding a discharge path for the gate of the high-side switch tube M1, and the drop rate of the driving voltage HS_Gate increases and quickly decreases to zero.

[0081] As can be seen from the above, compared with the traditional gate drive circuit, this application is based on Figure 6 The gate drive circuit shown, a novel gate drive circuit 10 is proposed, which can ensure that the voltage overshoot is reduced under the premise of unchanged switching loss, and effectively reduce the electromagnetic interference and overvoltage risk of the high-side switch tube M1.

[0082] The present application also discloses a voltage converter, including the above-mentioned gate drive circuit. The voltage converter adopts the above-mentioned gate drive circuit to improve the efficiency and reliability of the voltage converter.

[0083] Since the processing and functions implemented by the voltage converter in this embodiment basically correspond to the embodiments, principles and examples of the aforementioned gate drive circuit, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0084] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A gate drive circuit, characterized in that: It includes a driving module, a start control module and a first switch module, wherein the driving module is electrically connected to the start control module and the first switch module respectively, the start control module is electrically connected to the first switch module, the driving module, the start control module and the first switch module are all used to be electrically connected to the gate of the high-side switch tube, and the start control module and the first switch module are both used to be electrically connected to the source of the high-side switch tube; The driving module is used to output a driving voltage according to the first signal and the second signal; When the high-side switch tube is in the first turn-on stage and the fourth turn-on stage, the turn-on control module is used to output a first control signal to the first switch module according to the driving voltage and the node voltage, and the node voltage is the voltage between the source of the high-side switch tube and the common end of the turn-on control module; the first switch module is used to be turned off according to the first control signal; when the high-side switch tube is in the second turn-on stage and the third turn-on stage, the turn-on control module is used to output a second control signal to the first switch module according to the driving voltage and the node voltage, and the first switch module is used to be turned on according to the second control signal; The first start-up stage is a stage corresponding to the process in which the gate-source voltage of the high-side switch tube gradually increases to the threshold voltage, the second start-up stage is a stage in which the gate-source voltage of the high-side switch tube is greater than or equal to the threshold voltage and less than the first preset value, the third start-up stage is a stage in which the gate-source voltage of the high-side switch tube is equal to the first preset value and remains unchanged within a preset time, and the fourth start-up stage is a stage in which the gate voltage of the high-side switch tube gradually increases to the bootstrap voltage; The start control module comprises a logic unit, a regulating unit and a signal output unit, wherein the regulating unit is electrically connected to the logic unit and the signal output unit respectively, and the signal output unit is electrically connected to the first switch module; The logic unit is used to output a first logic voltage signal to the adjustment unit according to the driving voltage and the node voltage, the adjustment unit is used to output an adjustment voltage to the signal output unit according to the first logic voltage signal and the driving voltage, and the signal output unit is used to output a control signal to the first switch module according to the adjustment voltage, the driving voltage and the node voltage, wherein the control signal includes the first control signal and the second control signal.

2. The gate driving circuit according to claim 1, characterized in that: The gate drive circuit further includes a shutdown control module and a second switch module, wherein the shutdown control module is electrically connected to the drive module and the second switch module respectively, and the shutdown control module and the second switch module are both used to be electrically connected to the gate of the high-side switch tube, and the shutdown control module and the second switch module are both used to be electrically connected to the source of the high-side switch tube; When the high-side switch is in the first turn-off stage, the turn-off control module is used to control the driving voltage to decrease from the initial value to the first preset value according to the second signal; when the high-side switch is in the second turn-off stage and the third turn-off stage, the on-resistance of the turn-off control module increases, and the turn-off control module is used to control the driving voltage to decrease from the first preset value to the second preset value; when the high-side switch is in the fourth turn-off stage, the second switch module is used to turn on according to the driving voltage; The first turn-off stage is a stage in which the gate voltage of the high-side switch tube gradually decreases from the bootstrap voltage to the first preset value, the second turn-off stage is a stage in which the gate-source voltage of the high-side switch tube is equal to the first preset value and remains unchanged for a preset time, the third turn-off stage is a stage in which the gate-source voltage of the high-side switch tube is greater than or equal to the threshold voltage and less than the first preset value, and the fourth turn-off stage is a stage in which the gate-source voltage of the high-side switch tube gradually decreases from the threshold voltage to zero.

3. The gate driving circuit according to claim 2, characterized in that: The driving module includes a first switch tube and a second switch tube, the source of the first switch tube is used to receive the bootstrap voltage, the gate of the first switch tube is used to receive the first signal, the drain of the first switch tube is electrically connected to the drain of the second switch tube, the start-up control module, the shutdown control module, the first switch module and the second switch module respectively, the gate of the second switch tube is electrically connected to the shutdown control module for receiving the second signal, and the source of the second switch tube is used to be electrically connected to the source of the high-side switch tube.

4. The gate driving circuit according to claim 1, characterized in that: The logic unit includes a third switch tube, a fourth switch tube and a first resistor, the gate of the third switch tube and the gate of the fourth switch tube are both used to receive the driving voltage, the source of the third switch tube is used to receive the bootstrap voltage, the drain of the third switch tube is electrically connected to the drain of the fourth switch tube and the adjustment unit respectively, the source of the fourth switch tube is electrically connected to the first end of the first resistor, and the second end of the first resistor is used to be electrically connected to the source of the high-side switch tube.

5. The gate driving circuit according to claim 1, characterized in that: The regulating unit includes a fifth switch tube, a second resistor and a first capacitor. The gate of the fifth switch tube is electrically connected to the logic unit, the source of the fifth switch tube is used to receive the driving voltage, the drain of the fifth switch tube is respectively electrically connected to the second end of the second resistor, the first end of the first capacitor and the signal output unit, the second end of the first capacitor is used to be electrically connected to the source of the high-side switch tube, and the first end of the second resistor is used to be electrically connected to the gate of the high-side switch tube.

6. The gate driving circuit according to claim 1, characterized in that: The signal output unit includes a sixth switch tube and a seventh switch tube, the gate of the sixth switch tube and the gate of the seventh switch tube are both electrically connected to the adjustment unit, the source of the sixth switch tube is used to be electrically connected to the gate of the high-side switch tube, the drain of the sixth switch tube is respectively electrically connected to the drain of the seventh switch tube and the first switch module, and the source of the seventh switch tube is used to be electrically connected to the source of the high-side switch tube.

7. The gate driving circuit according to claim 1, characterized in that: The first switch module includes an eighth switch tube, the gate of the eighth switch tube is electrically connected to the start-up control module, the drain of the eighth switch tube is used to be electrically connected to the gate of the high-side switch tube, and the source of the eighth switch tube is used to be electrically connected to the source of the high-side switch tube.

8. The gate driving circuit according to claim 2, characterized in that: The shutdown control module includes a ninth switch tube and a first inverter, the gate of the ninth switch tube is electrically connected to the output end of the first inverter, the source of the ninth switch tube is used to be electrically connected to the gate of the high-side switch tube, the drain of the ninth switch tube is used to be electrically connected to the source of the high-side switch tube, and the input end of the first inverter is electrically connected to the driving module; The second switch module includes a tenth switch tube and a second inverter, the input end of the second inverter and the drain of the tenth switch tube are both used to be electrically connected to the gate of the high-side switch tube, the output end of the second inverter is electrically connected to the gate of the tenth switch tube, and the source of the tenth switch tube is used to be electrically connected to the source of the high-side switch tube.

9. A voltage converter, characterized in that: The gate drive circuit comprises the gate drive circuit as described in any one of claims 1 to 8.

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