WO2021012223A1

WO2021012223A1 - Bridge type silicon carbide field effect transistor driving circuit

Info

Publication number: WO2021012223A1
Application number: PCT/CN2019/097536
Authority: WO
Inventors: 谢飞; 赵德琦; 吴壬华
Original assignee: 深圳欣锐科技股份有限公司
Priority date: 2019-07-24
Filing date: 2019-07-24
Publication date: 2021-01-28
Also published as: CN111357179A; CN111357179B

Abstract

An embodiment of the present application discloses a bridge type silicon carbide field effect transistor driving circuit, wherein the circuit comprises a first silicon carbide field effect transistor circuit, a second silicon carbide field effect transistor circuit, a first driving module, a second driving module, a driving chip and a weak level control module; the first silicon carbide field effect transistor circuit is electrically connected with the first driving module, the driving chip and the second silicon carbide field effect transistor circuit respectively, the second silicon carbide field effect transistor circuit is electrically connected with the second driving module and the driving chip respectively, and the driving chip is electrically connected with the weak level control module. The embodiment of the present application can realize a fast turn-off of the silicon carbide field effect transistor without needing a complex negative voltage driving circuit, thereby reducing the complexity of the circuit, and improving the applicability of the circuit.

Description

Bridge type silicon carbide field effect tube drive circuit

Technical field

The invention relates to the technical fields of power supplies and power electronics, and in particular to a bridge type silicon carbide field effect tube drive circuit.

Background technique

With the continuous development of switching power supply technology, the demand for switching power supply in the market has become higher and higher, not only to be safe, reliable, efficient, but also to be the smallest. Miniaturization of the volume requires higher power density. As the core component of the switching power supply, the switch tube is bound to require minimum loss, higher voltage resistance, and better performance. Compared with traditional silicon MOS tubes, silicon carbide MOS tubes have higher voltage resistance, lower on-resistance, and extremely small junction capacitance, and are favored by more and more power supply manufacturers, especially in high-power power supplies. In order to take into account the volume, the switching frequency is often relatively high. The traditional silicon MOS tube has a large junction capacitance and a slower turn-off. In the high switching frequency state, the MOS tube has a large turn-off loss. At this time, silicon carbide becomes the most Best choice. However, due to the low turn-on threshold voltage of the silicon carbide MOS tube, when turning off, a negative voltage of about -4V to -2V is required to ensure reliable turn-off. Especially for the silicon carbide used in the bridge-type upper and lower tubes, the driving circuit is often very complicated, not only requires an additional negative pressure circuit, but also has the problem of not sharing the ground between the upper and lower tubes.

Summary of the invention

The embodiment of the application provides a bridge-type silicon carbide field effect transistor drive circuit, which aims to solve the problem that the silicon carbide field effect transistor drive circuit in the prior art requires an additional negative voltage circuit to turn off the silicon carbide field effect transistor. The application embodiment can realize the rapid turn-off of the silicon carbide field effect transistor without a complicated negative voltage driving circuit, thereby reducing the complexity of the circuit and improving the applicability of the circuit.

In the first aspect, embodiments of the present application provide a bridge-type silicon carbide field effect transistor drive circuit, which includes a first silicon carbide field effect transistor circuit, a second silicon carbide field effect transistor circuit, a first drive module, and a second Drive module, drive chip and weak level control module;

The first silicon carbide field effect tube circuit is electrically connected to the first driving module, the driving chip, and the second silicon carbide field effect tube circuit, respectively, and the second silicon carbide field effect tube circuit is respectively connected to The second driving module is electrically connected to the driving chip, and the driving chip is electrically connected to the weak level control module;

The weak level control module is used to control the driving chip so that the driving chip can control the driving signals output by the first driving module and the second driving module;

The driving chip is used to input the first driving signal output by the first driving module into the first silicon carbide field effect transistor circuit to control the on and off of the first silicon carbide field effect transistor, and use The second driving signal output by the second driving module is input to the second silicon carbide field effect transistor circuit to control the on and off of the second silicon carbide field effect transistor, wherein the first drive The signal includes a first positive pressure drive signal and a first negative pressure drive signal. The first positive pressure drive signal is used to drive the first silicon carbide field effect transistor to turn on, and the first negative pressure drive signal is used to turn off. Turn off the first silicon carbide field effect transistor, the second drive signal includes a second positive pressure drive signal and a second negative pressure drive signal, and the second positive pressure drive signal is used to drive the second silicon carbide field The effect tube is turned on, and the second negative pressure driving signal is used to turn off the second silicon carbide field effect tube.

With reference to the first aspect, in a first possible implementation manner of the first aspect, the first silicon carbide field effect transistor circuit includes a first silicon carbide field effect transistor Q1, a resistor R11, a resistor R12, a resistor R13, and a diode D1 ；

The second silicon carbide field effect transistor circuit includes a second silicon carbide field effect transistor Q2, a resistor R21, a resistor R22, a resistor R23, and a diode D2;

Wherein, the drain of the first silicon carbide field effect transistor Q1 is connected to the power connection VBUS for providing a preset voltage signal for the first silicon carbide field effect transistor Q1; one end of the resistor R11 is connected to the first The gate of the silicon carbide field effect transistor Q1 is connected, the other end of the resistor R11 is connected to the positive terminal of the diode D1, the negative terminal of the diode D1 is then connected to the drive chip, and one end of the resistor R12 is connected to One end of the resistor R11 is connected, the other end of the resistor R12 is connected to the negative terminal of the diode D1, and one end of the resistor R13 is connected to one end of the resistor R12, and the other end of the resistor R13 is connected to The first driving module is connected; the drain of the second silicon carbide field effect transistor Q2 is connected to the source of the first silicon carbide field effect transistor Q1, and the source of the second silicon carbide field effect transistor Q2 Grounded, one end of the resistor R21 is connected to the gate of the second silicon carbide field effect transistor Q2, the other end of the resistor R21 is connected to the positive terminal of the diode D2, and the negative terminal of the diode D2 It is then connected to the drive chip, one end of the resistor R22 is connected to one end of the resistor R21, the other end of the resistor R22 is connected to the negative end of the diode D2, and one end of the resistor R23 is connected to the resistor R21 One end of R22 is connected, and the other end of the resistor R23 is connected to the second driving module.

With reference to the first aspect or the first possible implementation of the first aspect, in a second possible implementation of the first aspect, the first drive module includes a first input terminal, a first forward Converter and a first drive output circuit, wherein the first input terminal is used to input a first signal into the first forward converter, and the first forward converter is used to boost the first signal And then passed to the first drive output circuit to output the first drive signal.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the first forward converter includes a magnetic reset module, a double-tap step-up transformer, and a third field effect Tube and pulse drive signal input terminal, wherein one end of the magnetic reset module is electrically connected to one end of the primary side of the double-tap step-up transformer, and the other end of the magnetic reset module is connected to the double-tap step-up transformer The other end of the primary side of the double-tap step-up transformer is electrically connected to the drain of the third field effect transistor, and the source of the third field effect transistor is grounded, The pulse drive signal input terminal is electrically connected to the gate of the third field effect transistor, and the pulse drive signal input terminal is used to input a first control signal that controls the on and off of the third field effect transistor , The magnetic reset module is used to demagnetize the double-tap step-up transformer when the third FET is turned off, and the double-tap step-up transformer is used to boost the first signal and then transfer it to the The first drive output circuit outputs the first drive signal.

With reference to the third possible implementation manner of the first aspect, in the fourth possible implementation manner of the first aspect, when the first control signal is at a high level, the third field effect transistor conducts After the first signal passes through the primary side of the double-tap step-up transformer, the signal energy is transferred to the secondary side of the double-tap step-up transformer for output.

With reference to the fourth possible implementation manner of the first aspect, in the fifth possible implementation manner of the first aspect, when the first control signal is at a low level, the third field effect transistor turns off Is off, the double-tap step-up transformer is demagnetized by the magnetic reset module.

In combination with the third possible implementation manner of the first aspect, the fourth possible implementation manner of the first aspect, or the fifth possible implementation manner of the first aspect, in the sixth possible implementation manner of the first aspect , The first drive output circuit includes a first positive drive output circuit and a first negative drive output circuit;

The first forward drive output circuit includes a first diode, N capacitors, a first resistor, and a first regulator tube; the N capacitors and the first resistor are connected in parallel, and the first regulator The cathode of the tube is connected to one end of the first resistor, the anode of the first voltage regulator tube is electrically connected to the other end of the first resistor, and the cathode of the first diode is connected to the first resistor. One end of the first diode is electrically connected, and the anode of the first diode is electrically connected to the first positive terminal of the secondary side of the double-tap step-up transformer, where N is an integer greater than zero;

The first negative drive output circuit includes a second diode, M capacitors, and a second resistor; the M capacitors and the second resistor are connected in parallel, and one end of the second resistor is connected to the double tap The second positive terminal of the secondary side of the step-up transformer is electrically connected. At the same time, one end of the second resistor is electrically connected to the other end of the first resistor, and the other end of the second resistor is electrically connected to the second resistor. The positive terminal of the diode is electrically connected, and the negative terminal of the second diode is electrically connected to the negative terminal of the secondary side of the double-tap step-up transformer, where M is an integer greater than zero.

With reference to the sixth possible implementation manner of the first aspect, in a seventh possible implementation manner of the first aspect, the drive chip includes a first drive signal input terminal, a first drive signal output terminal, and a first ground terminal And a first weak level control input terminal; the first drive signal input terminal is electrically connected to the first forward drive output circuit, and the first drive signal output terminal is connected to the first silicon carbide field effect transistor circuit Are electrically connected, the first ground terminal is electrically connected to the first negative drive output circuit, the first weak level control input terminal is used to input a weak level control signal, and the weak level control signal is used to control The turn-on and turn-off between the first drive signal input terminal, the first drive signal output terminal and the first ground terminal controls the turn-on and turn-off of the first silicon carbide field effect transistor.

With reference to the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, when the weak level control signal is at a high level, the first drive signal input terminal And the first drive signal output terminal is connected, the first positive voltage drive signal output by the first forward drive output circuit is input to the drive chip through the first drive signal input terminal, and then the The first driving signal output terminal is output to the grid of the first silicon carbide field effect tube in the first silicon carbide field effect tube circuit, and the first silicon carbide field effect tube is turned on.

With reference to the seventh possible implementation manner of the first aspect or the eighth possible implementation manner of the first aspect, in the ninth possible implementation manner of the first aspect, when the weak level control signal is low level In the case that the first driving signal output terminal and the first ground terminal are conducted, the first negative pressure driving signal output by the first negative driving output circuit is transmitted to the first silicon carbide field The gate of the first silicon carbide field effect transistor in the effect tube circuit is then input to the driving chip through the first driving signal output terminal, and then returned to the first negative direction from the first ground terminal The driving output circuit forms a signal opposite to the first positive voltage driving signal on the gate of the first silicon carbide field effect tube.

In summary, the embodiments of the present application provide a bridge-type silicon carbide field effect tube driving circuit, which aims to solve the need for an additional negative pressure circuit to turn off the silicon carbide field effect tube in the silicon carbide field effect tube driving circuit in the prior art. The problem of using the embodiment of the present application can realize the rapid turn-off of the silicon carbide field effect transistor without a complicated negative voltage driving circuit, thereby reducing the complexity of the circuit and improving the applicability of the circuit.

Description of the drawings

The following will introduce the drawings that need to be used in the embodiments of the present application.

FIG. 1 is a schematic structural diagram of a bridge silicon carbide field effect transistor driving circuit provided by an embodiment of the application;

2 is a schematic diagram of the structure of the first silicon carbide field effect tube circuit and the second silicon carbide field effect tube circuit described in FIG. 1;

FIG. 3 is a schematic structural diagram of the first driving module described in FIG. 1;

4 is a schematic diagram of the structure of the first positive driving output circuit and the second negative driving output circuit of FIG. 3;

FIG. 5 is a schematic diagram of the structure of the driving chip and the weak level control module described in FIG. 1.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present application.

Please refer to FIG. 1. FIG. 1 is a schematic structural diagram of a bridge silicon carbide field effect transistor drive circuit provided by an embodiment of the application. The bridge silicon carbide field effect transistor drive circuit provided by an embodiment of the application includes a first silicon carbide field The effect tube circuit 101, the second silicon carbide field effect tube circuit 102, the first driving module 103, the second driving module 104, the driving chip 105 and the weak level control module 106. The first silicon carbide field effect tube circuit 101 is electrically connected to the first driving module 103, the driving chip 105 and the second silicon carbide field effect tube circuit 102, respectively, and the second silicon carbide field effect tube circuit 102 is respectively connected to the second driving module 104 It is electrically connected to the driving chip 105, the first driving module 103 and the second driving module 104 are electrically connected to the driving chip 105 respectively, and the driving chip 105 is electrically connected to the weak level control module 106.

In a specific embodiment, the weak level control module 106 is used to control the drive chip 105 so that the drive chip 105 can control the drive signals output by the first drive module 103 and the second drive module 104; the drive chip 105 is used to control the first drive module The first drive signal output by 103 is input to the first silicon carbide field effect transistor circuit 101 to control the on and off of the first silicon carbide field effect transistor, and is used to input the second drive signal output by the second drive module 104 into the first silicon carbide field effect transistor. The two silicon carbide field effect transistor circuit 102 controls the on and off of the second silicon carbide field effect transistor, wherein the first drive signal includes a first positive pressure drive signal and a first negative pressure drive signal, so The first positive pressure drive signal is used to drive the first silicon carbide field effect transistor to turn on, the first negative pressure drive signal is used to turn off the first silicon carbide field effect transistor, and the second drive signal It includes a second positive pressure drive signal and a second negative pressure drive signal, the second positive pressure drive signal is used to drive the second silicon carbide field effect transistor to turn on, and the second negative pressure drive signal is used to turn off The second silicon carbide field effect tube.

Please refer to FIG. 2, the first silicon carbide field effect transistor circuit 101 includes a first silicon carbide field effect transistor Q1, a resistor R11, a resistor R12, a resistor R13, and a diode D1. Wherein, the drain of the first silicon carbide field effect transistor Q1 is connected to the power connection VBUS, and is used to provide a preset voltage signal for the first silicon carbide field effect transistor Q1. The preset voltage can be 5V or 12V, etc.; one end of the resistor R11 Connected to the gate of the first silicon carbide field effect transistor Q1, the other end of the resistor R11 is connected to the positive terminal of the diode D1, the negative terminal of the diode D1 is then connected to the driving chip 105, one end of the resistor R12 is connected to one end of the resistor R11, The other end of the resistor R12 is connected to the negative terminal of the diode D1, one end of the resistor R13 is connected to one end of the resistor R12, and the other end of the resistor R13 is connected to the first driving module. This connection is for when the first silicon carbide field effect transistor Q1 needs to be driven to turn on, the positive voltage driving signal output by the first driving module 103 is output through the driving chip 105, and then input to the first silicon carbide field effect transistor Q1 through the resistor R12 The first silicon carbide field effect transistor Q1 is turned on. When the first silicon carbide field effect transistor Q1 needs to be turned off, the first driving module 103 outputs a negative pressure driving signal, which passes through the resistor R13 Flowing to the gate of the first silicon carbide field effect transistor Q1, the gate of the first silicon carbide field effect transistor Q1 forms a signal opposite to the signal direction when it is turned on, so that the first silicon carbide field effect transistor Q1 can be quickly turned off .

The second silicon carbide field effect transistor circuit 102 includes a second silicon carbide field effect transistor Q2, a resistor R21, a resistor R22, a resistor R23, and a diode D2. Wherein, the drain of the second silicon carbide field effect transistor Q2 is connected to the source of the first silicon carbide field effect transistor Q1, and the source of the second silicon carbide field effect transistor Q2 is grounded, so that the connection makes the first silicon carbide field effect transistor Q1 and the second silicon carbide field effect transistor Q2 share the ground, thereby simplifying the circuit, reducing the complexity of the circuit, and improving the applicability of the circuit; in addition, one end of the resistor R21 is connected to the gate of the second silicon carbide field effect transistor Q2 Connected, the other end of the resistor R21 is connected to the positive end of the diode D2, the negative end of the diode D2 is connected to the drive chip 105, one end of the resistor R22 is connected to one end of the resistor R21, and the other end of the resistor R22 is connected to the negative end of the diode D2 In addition, one end of the resistor R23 is connected to one end of the resistor R22, and the other end of the resistor R23 is connected to the second driving module. This connection is for when the second silicon carbide field effect transistor Q2 needs to be driven to turn on, the positive voltage driving signal output by the second driving module 104 is output through the driving chip 105, and then input to the second silicon carbide field effect transistor Q2 through the resistor R22 The gate of the second silicon carbide field effect transistor Q2 is turned on. When the second silicon carbide field effect transistor Q2 needs to be turned off, the second driving module 104 outputs a negative voltage driving signal, and the control signal flows to the first through the resistor R23 The gate of the silicon carbide field effect transistor Q2 forms a signal opposite to the signal direction when it is turned on on the gate of the second silicon carbide field effect transistor Q2, so that the second silicon carbide field effect transistor Q2 can be quickly turned off.

Referring to FIG. 3, the first driving module 103 includes an input terminal 1031, a forward converter 1032, and a drive output circuit 1033; wherein the input terminal 1031 is connected to the forward converter 1032 for inputting a preset voltage signal into the forward converter The preset voltage can be 12V, etc.; the forward converter 1032 is connected to the drive output circuit 1033, and the forward converter 1032 is used to boost the signal input from the input terminal 1031 and transfer it to the drive output circuit 1033 for output.

Specifically, the forward converter 1032 includes a resistor R31, a capacitor C3, a double-tap step-up transformer T1, a field effect transistor Q3, a pulse drive signal input terminal PWM1, a resistor R32, and a resistor R33. Among them, the resistor R31 and the capacitor C3 form a magnetic reset Module, the secondary side of the double-tap step-up transformer T1 includes a first positive terminal, a second positive terminal and a negative terminal. The first positive terminal is used to output the positive control signal that drives the first silicon carbide field effect tube to conduct, that is, the positive voltage Driving signal, the second positive terminal is used to output the reverse control signal for quickly turning off the first silicon carbide field effect tube, that is, the negative pressure driving signal. The negative pressure driving signal passes through the first silicon carbide field effect tube and then is returned to the dual by the driving chip 105. The negative terminal of the tapped step-up transformer T1 forms a loop. Specifically, the primary input terminal of the double-tap boost transformer T1 is connected to the input terminal 1031, the primary output terminal of the double-tap boost transformer T1 is connected to the drain of the FET Q3, and the gate of the FET Q3 is connected to the resistor. R32 is connected and then connected to the pulse drive signal input terminal PWM1, the source of the field effect transistor Q3 is grounded, and the resistor R33 is connected to the gate of the field effect transistor Q3 and then grounded to limit the current. In addition, one end of the resistor R31 is connected to the double The primary input end of the tapped step-up transformer T1 is connected, the other end of the resistor R31 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the primary output end of the double-tap step-up transformer T1. When the drive signal input by the pulse drive signal input terminal PWM1 is high, the FET Q3 is turned on, and the signal input from the input terminal 1031 is boosted by the double-tap step-up transformer T1 and then output; when the pulse drive signal input terminal PWM1 inputs When the drive signal is low, the field effect transistor Q3 is turned off. At this time, the double-tap step-up transformer T1 is demagnetized by the magnetic reset module to avoid saturation, thereby achieving a stable supply voltage for the drive circuit.

Specifically, the drive output circuit 1033 includes a first forward drive output circuit and a first negative drive output circuit. Please also refer to FIG. 4. The first forward drive output circuit includes a diode D3, N capacitors, a resistor R41, and A Zener diode D5. In this embodiment, N is 5 for illustration. The 5 capacitors are respectively labeled C4, C5, C6, C7 and C8; the first negative drive output circuit includes a diode D4 and M capacitors. And a resistor R42. In this embodiment, M is 3 for illustration, and the three capacitors are labeled C9, C10, and C11, respectively. Among them, the anode of the diode D3 is connected to the first positive terminal of the secondary side of the double-tap step-up transformer T1, and the capacitor C4, the capacitor C5, the capacitor C6, the resistor R41, the Zener diode D5, the capacitor C7 and the capacitor C8 are connected in parallel. Specifically, The cathode of the Zener diode D5 is connected to the cathode of the diode D3, the anode of the Zener diode D5 is connected to the second positive terminal of the secondary side of the double-tap step-up transformer T1, and the capacitor C9, the capacitor C10, the capacitor C11 and the resistor R42 are connected in parallel At the same time, one end of the capacitor C9, the capacitor C10, the capacitor C11 and the resistor R42 is connected to the second positive terminal of the secondary side of the double-tap step-up transformer T1. The other end of the capacitor C9, the capacitor C10, the capacitor C11 and the resistor R42 is connected to the diode D4 The anode is connected, and the cathode of the diode D4 is connected to the cathode of the secondary side of the double-tap step-up transformer T1. Capacitor C4, Capacitor C5, Capacitor C6, Capacitor C7, Capacitor C8, Capacitor C9, Capacitor C10 and Capacitor C11 are used for energy storage and filtering, resistors R41 and R42 are used for current limiting, and Zener tube D5 is used for maintaining voltage stability .

It should be noted that the structural composition, connection mode, and the functions of corresponding circuits and components of the second driving module 104 and the first driving module 103 can be completely the same. The second driving module 104 also includes an input terminal 1031 and a forward converter 1032. As with the drive output circuit 1033, the drive output circuit 1033 also includes a forward drive output circuit and a reverse drive output circuit. To facilitate the distinction, the forward drive output circuit and the reverse drive output circuit included in the second drive module 104 are respectively called the first Two forward drive output circuits and a second reverse drive output circuit.

Please refer to Figure 5, the driver chip 105 includes 16 pins, of which pin 1 is used to input control signals to control the closing and disconnection between pins 16, pins 15, and 14, and pin 16 is a drive signal Pin 15 is the output end of the signal, pin 14 is the ground end; Pin 2 is used to input control signals to control the closing and disconnection between

pins

11, 10 and 9, pin 11 is the input terminal of the drive signal, pin 10 is the output terminal of the signal, and pin 9 is the ground terminal; pins 13 and 12 have no special purpose and are usually left floating, and pins 3 and 8 are used to drive the chip 105 power supply, pin 4 is used for grounding, pin 5 is an enable pin, used to control the enable and disable of the chip. The weak level control module 106 includes control signal input terminals PWM2 and PWM3, ground terminal GND, power supply input terminal VIN, six resistors and five capacitors. The six resistors are marked as R51, R52, R53, R54, R55 and R56, respectively. The capacitors are labeled C12, C13, C14, C15, and C16. Specifically, the control signal input terminal PWM2 is connected to the resistor R53 and then connected to pin 1 for inputting the first control signal, and the control signal input terminal PWM3 is connected to the resistor R54 and then connected to pin 2 for inputting the second control signal. Pin 4 and pin 5 are connected to the ground terminal GND, the power input terminal VIN is connected to the resistor R55 and then connected to pin 3 to supply power to the drive chip 105. The remaining capacitors and resistors are connected to the corresponding pins and grounded. The capacitors are mainly used For filtering, resistors are mainly used for current limiting. In addition, pin 16 is connected to the first positive drive output circuit, pin 15 is connected to the first silicon carbide field effect transistor circuit 101, and the first silicon carbide field effect transistor circuit 101 is then connected to the first negative drive output circuit. 14 is connected to the first negative drive output circuit; pin 13 and pin 12 are left floating; pin 11 is connected to the second positive drive output circuit, pin 10 is connected to the second silicon carbide field effect transistor circuit 102, the second silicon carbide The field effect tube circuit 102 is then connected to the second negative driving output circuit, and the pin 9 is connected to the second negative driving output circuit.

When the control signal input by the control signal input terminal PWM2 is at a high level, pins 16 and 15 are closed and conductive, and the positive voltage drive signal output by the first forward drive output circuit is input to the drive chip 105 through pin 16. Then output to the first silicon carbide FET circuit 101 through pin 15 to turn on the first silicon carbide FET; when the control signal input from the control signal input terminal PWM2 is low, pin 16 and lead Pin 15 is disconnected, pin 15 and pin 14 are closed and turned on, the negative drive signal output by the first negative drive output circuit passes through the first silicon carbide field effect transistor circuit 101, and then is input to the drive chip 105 from pin 15 , And then output to the first negative drive output circuit through pin 14 to form a loop to realize the rapid turn-off of the first silicon carbide field effect transistor. This is because the negative drive signal output by the first negative drive output circuit is in the first negative drive output circuit. A signal in the opposite direction to the positive pressure driving signal driving the first silicon carbide field effect tube is formed on the grid of a silicon carbide field effect tube, thereby rapidly weakening the positive driving force of the first silicon carbide field effect tube. The driving signal is pressed, so that the first silicon carbide field effect transistor is quickly turned off.

In the same way, when the control signal input by the control signal input terminal PWM3 is high, the pins 11 and 10 are closed and turned on, and the positive voltage drive signal output by the second forward drive output circuit is driven by the pin 11 input The chip 105 is then output to the second silicon carbide field effect transistor circuit 102 through pin 10 to turn on the second silicon carbide field effect transistor; when the control signal input from the control signal input terminal PWM3 is low, the pin 11 and pin 10 are disconnected, pin 10 and pin 9 are closed and turned on, the negative drive signal output by the second negative drive output circuit passes through the second silicon carbide field effect tube circuit 102, and then is input from pin 10 The driver chip 105 is then output to the second negative drive output circuit through pin 9 to form a loop, thereby realizing the rapid turn-off of the second silicon carbide field effect transistor, which is due to the negative voltage drive output by the second negative drive output circuit The signal forms on the gate of the second silicon carbide field effect tube a signal in the opposite direction to the positive pressure driving signal that drives the second silicon carbide field effect tube to conduct, thereby rapidly weakening the driving of the second silicon carbide field effect tube. The positive voltage driving signal is turned on, so that the second silicon carbide field effect transistor is quickly turned off.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the application, not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: It is still possible to modify the technical solutions described in the foregoing embodiments, or equivalently replace some or all of the technical features; these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the application range.

Claims

A bridge type silicon carbide field effect tube drive circuit, which is characterized by comprising a first silicon carbide field effect tube circuit, a second silicon carbide field effect tube circuit, a first drive module, a second drive module, a drive chip and a weak level Control module

The first silicon carbide field effect tube circuit is electrically connected to the first driving module, the driving chip, and the second silicon carbide field effect tube circuit, respectively, and the second silicon carbide field effect tube circuit is respectively connected to The second driving module is electrically connected to the driving chip, and the driving chip is electrically connected to the weak level control module;

The weak level control module is used to control the driving chip;

The driving chip is used to input the first driving signal output by the first driving module into the first silicon carbide field effect transistor circuit to control the on and off of the first silicon carbide field effect transistor, and use The second driving signal output by the second driving module is input to the second silicon carbide field effect transistor circuit to control the on and off of the second silicon carbide field effect transistor, wherein the first drive The signal includes a first positive pressure drive signal and a first negative pressure drive signal. The first positive pressure drive signal is used to drive the first silicon carbide field effect transistor to turn on, and the first negative pressure drive signal is used to turn off. Turn off the first silicon carbide field effect transistor, the second drive signal includes a second positive pressure drive signal and a second negative pressure drive signal, and the second positive pressure drive signal is used to drive the second silicon carbide field The effect tube is turned on, and the second negative pressure driving signal is used to turn off the second silicon carbide field effect tube.
The bridge-type silicon carbide field effect transistor drive circuit of claim 1, wherein:

The first silicon carbide field effect tube circuit includes a first silicon carbide field effect tube Q1, a resistor R11, a resistor R12, a resistor R13, and a diode D1;

The second silicon carbide field effect transistor circuit includes a second silicon carbide field effect transistor Q2, a resistor R21, a resistor R22, a resistor R23, and a diode D2;

Wherein, the drain of the first silicon carbide field effect transistor Q1 is connected to the power connection VBUS for providing a preset voltage signal for the first silicon carbide field effect transistor Q1; one end of the resistor R11 is connected to the first The gate of the silicon carbide field effect transistor Q1 is connected, the other end of the resistor R11 is connected to the positive terminal of the diode D1; the negative terminal of the diode D1 is connected to the drive chip; one end of the resistor R12 is connected to the One end of the resistor R11 is connected, the other end of the resistor R12 is connected to the negative terminal of the diode D1; one end of the resistor R13 is connected to one end of the resistor R12, and the other end of the resistor R13 is connected to the A driving module is connected; the drain of the second silicon carbide field effect transistor Q2 is connected to the source of the first silicon carbide field effect transistor Q1, the source of the second silicon carbide field effect transistor Q2 is grounded, so One end of the resistor R21 is connected to the gate of the second silicon carbide field effect transistor Q2, the other end of the resistor R21 is connected to the positive terminal of the diode D2, and the negative terminal of the diode D2 is connected to the driving chip One end of the resistor R22 is connected to one end of the resistor R21, the other end of the resistor R22 is connected to the negative end of the diode D2, one end of the resistor R23 is connected to one end of the resistor R22, The other end of R23 is connected with the second driving module.
The bridge silicon carbide field effect transistor driving circuit according to claim 1 or 2, wherein:

The first drive module includes a first input terminal, a first forward converter, and a first drive output circuit that are sequentially connected, wherein the first input terminal is used to input a first signal into the first forward converter The first forward converter is used to boost the first signal and transfer it to the first drive output circuit to output the first drive signal.
The bridge silicon carbide field effect tube drive circuit of claim 3, wherein the first forward converter includes a magnetic reset module, a double-tap boost transformer, a third field effect tube and a pulse drive signal input One end of the magnetic reset module is electrically connected to one end of the primary side of the double-tap step-up transformer, and the other end of the magnetic reset module is connected to the other end of the primary side of the double-tap step-up transformer Electrically connected, the other end of the primary side of the double-tap step-up transformer is electrically connected to the drain of the third field effect transistor, the source of the third field effect transistor is grounded, and the pulse drive signal is input The terminal is electrically connected to the grid of the third field effect tube, the pulse drive signal input terminal is used to input a first control signal that controls the turning on and off of the third field effect tube, and the magnetic reset module Used to demagnetize the double-tap step-up transformer when the third FET is turned off, and the double-tap step-up transformer is used to boost the first signal and transmit it to the first drive output circuit for The first driving signal is output.
The bridge silicon carbide field effect transistor drive circuit of claim 4, wherein when the first control signal is at a high level, the third field effect transistor is turned on, and the first After the signal passes through the primary side of the double-tap step-up transformer, the signal energy is transferred to the secondary side of the double-tap step-up transformer for output.
The bridge silicon carbide field effect transistor drive circuit of claim 5, wherein when the first control signal is at a low level, the third field effect transistor is turned off, and the double-tap The step-up transformer is demagnetized by the magnetic reset module.
7. The bridge silicon carbide field effect transistor drive circuit of claims 4-6, wherein the first drive output circuit comprises a first positive drive output circuit and a first negative drive output circuit;

The first forward drive output circuit includes a first diode, N capacitors, a first resistor, and a first regulator tube; the N capacitors and the first resistor are connected in parallel, and the first regulator The cathode of the tube is connected to one end of the first resistor, the anode of the first voltage regulator tube is electrically connected to the other end of the first resistor, and the cathode of the first diode is connected to the first resistor. One end of the first diode is electrically connected, and the anode of the first diode is electrically connected to the first positive terminal of the secondary side of the double-tap step-up transformer, where N is an integer greater than zero;

The first negative drive output circuit includes a second diode, M capacitors, and a second resistor; the M capacitors and the second resistor are connected in parallel, and one end of the second resistor is connected to the double tap The second positive terminal of the secondary side of the step-up transformer is electrically connected. At the same time, one end of the second resistor is electrically connected to the other end of the first resistor, and the other end of the second resistor is electrically connected to the second resistor. The positive terminal of the diode is electrically connected, and the negative terminal of the second diode is electrically connected to the negative terminal of the secondary side of the double-tap step-up transformer, where M is an integer greater than zero.
The bridge silicon carbide field effect transistor drive circuit of claim 7, wherein the drive chip comprises a first drive signal input terminal, a first drive signal output terminal, a first ground terminal and a first weak level control Input terminal; the first drive signal input terminal is electrically connected to the first forward drive output circuit, the first drive signal output terminal is electrically connected to the first silicon carbide field effect transistor circuit, the The first ground terminal is electrically connected to the first negative drive output circuit, the first weak level control input terminal is used to input a weak level control signal, and the weak level control signal is used to control the first drive signal The turn-on and turn-off between the input terminal, the first drive signal output terminal and the first ground terminal are used to control the turn-on and turn-off of the first silicon carbide field effect transistor.
The bridge silicon carbide field effect transistor drive circuit of claim 8, wherein when the weak level control signal is at a high level, the first drive signal input terminal and the first drive signal The signal output terminal is turned on, and the first positive voltage drive signal output by the first forward drive output circuit is input to the drive chip through the first drive signal input terminal, and then the first drive signal output terminal The output is output to the grid of the first silicon carbide field effect tube in the first silicon carbide field effect tube circuit, and the first silicon carbide field effect tube is turned on.
The bridge silicon carbide field effect transistor drive circuit according to claim 8 or 9, characterized in that, when the weak level control signal is low level, the first drive signal output terminal and the first drive signal A ground terminal is turned on, and the first negative voltage drive signal output by the first negative drive output circuit is transmitted to the gate of the first silicon carbide field effect tube in the first silicon carbide field effect tube circuit And then input the drive chip through the first drive signal output terminal, and then return to the first negative drive output circuit from the first ground terminal, at the gate of the first silicon carbide field effect transistor The pole forms a signal opposite to the direction of the first positive voltage drive signal.