Single-power-supply negative-voltage power supply type IC-MOS driving circuit

Abstract

The utility model provides an IC-MOS drive circuit powered by single power supply negative voltage. The drive circuit comprises a power supply unit (1), a drive unit (2), a turn-off unit (3), a negative voltage generation circuit (4) and a power conversion circuit (5). The power supply unit (1) is connected with the driving unit (2), the negative voltage generating circuit (4) and a single power supply positive electrode VDD; the driving unit (2) is connected with the turn-off unit (3) and the power conversion circuit (5); the turn-off unit (3) is connected with the driving unit (2), the negative voltage generation circuit (4) and the power conversion circuit (5); the negative voltage generation circuit (4) is connected with the power supply unit (1), the driving unit (2), the turn-off unit (3), the single power supply positive electrode VDD and the power conversion circuit (5); power efficiency is improved, and driving quality is improved.

Description

Technical Field

[0001] This utility model belongs to the field of electronic circuit power supply technology, specifically relating to a SiC-MOS driving circuit with single power supply negative voltage. Background Technology

[0002] With the widespread use of power electronic devices in new energy, electric vehicles, industry and aerospace, the demand for devices with lower semiconductor losses, high temperature resistance and faster switching speed is increasing. Compared with Si materials, SiC power devices can achieve high frequency, high blocking voltage and low on-resistance characteristics. The drift layer impedance of SiC MOSFET is lower than that of silicon MOSFET, but due to the current technological limitations, the mobility of the MOS channel of SiC MOSFET is relatively low, so the impedance of the channel is relatively high. In order to obtain low on-resistance, the gate voltage of SiC MOSFET must be higher than that of silicon. Furthermore, since SiC MOSFETs have a low turn-on voltage, a negative voltage is usually introduced to turn them off reliably. Commonly, a drive voltage of +18V / -5V is used for the SiC MOSFET drive circuit. The +18V turn-on voltage results in low on-resistance of the SiC MOSFET, reducing turn-on losses, while the -5V turn-off voltage ensures rapid turn-off and prevents mis-turn-on. In some applications, the use of SiC MOSFETs is limited when there is only a single power supply. Therefore, it is necessary to propose a SiC-MOS drive circuit with a single negative power supply to at least partially solve the problems existing in the prior art. Utility Model Content

[0003] To at least partially solve the above problems, this utility model provides a single-power-supply negative-voltage SiC-MOS driving circuit, comprising:

[0004] The system includes a power supply unit, a drive unit, a shutdown unit, a negative voltage generating circuit, and a power conversion circuit. The power supply unit is connected to the drive unit, the negative voltage generating circuit, and the single power supply positive terminal VDD. The drive unit is connected to the shutdown unit and the power conversion circuit. The shutdown unit is connected to the drive unit, the negative voltage generating circuit, and the power conversion circuit. The negative voltage generating circuit is connected to the power supply unit, the drive unit, the shutdown unit, the single power supply positive terminal VDD, and the power conversion circuit.

[0005] Preferably, the power supply unit includes: capacitor C2 and an external terminal; the positive terminal of capacitor C2 is connected in parallel to the positive terminal of the single power supply VDD, the collector of the transistor Q3 of the driving unit, and one end of the resistor R5 of the negative voltage generation circuit; the negative terminal of capacitor C2 is connected to the external terminal.

[0006] Preferably, the driving unit includes: a transistor Q3 and a resistor R7; the base of transistor Q3 is connected to the first base voltage terminal Vg1; the collector of transistor Q3 is connected to the positive terminal of capacitor C2, the positive terminal of the single power supply VDD, and one end of resistor R5 of the negative voltage generation circuit; the emitter of transistor Q3 is connected to one end of resistor R7; the other end of resistor R7 is connected to one end of resistor R8 of the turn-off unit and the gate G of SiC-MOS transistor Q9 of the power conversion circuit.

[0007] Preferably, the shutdown unit includes:

[0008] Transistor Q10, resistor R8 and external terminals; collector of transistor Q10 connected to one end of resistor R8; base of transistor Q10 connected to the second base voltage terminal Vg2; collector of transistor Q10 connected to the other end of resistor R8; emitter of transistor Q10 connected to one end of capacitor C1 of the negative voltage generating circuit, the positive terminal of diode Z2 and the emitter of transistor Q11 in parallel external terminals.

[0009] Preferably, the negative voltage generating circuit includes: resistor R5, resistor R6, capacitor C1, diode Z2 and transistor Q11; the other end of resistor R5 is connected in parallel to one end of resistor R6, the other end of capacitor C1, the negative terminal of diode Z2, the source S of SiC-MOS transistor Q9 of the power conversion circuit, and one end of resistor R1; the other end of resistor R6 is connected to the collector of transistor Q11; the base of transistor Q11 is connected to the third base voltage terminal Vg3.

[0010] Preferably, the power conversion circuit includes:

[0011] The circuit consists of inductor L2-D, SiC-MOS transistor Q9, and resistor R1. One end of inductor L2-D is connected to the voltage bus VBUS. The other end of inductor L2-D is connected to the drain (D) of SiC-MOS transistor Q9. The source (S) of SiC-MOS transistor Q9 is connected to one end of resistor R1, the other end of resistor R5, the other end of capacitor C1, the negative terminal of diode Z2, and one end of resistor R6. The gate (G) of SiC-MOS transistor Q9 is connected to the other end of resistor R7 and one end of resistor R8. The other end of resistor R1 is grounded.

[0012] The beneficial effects of this utility model are:

[0013] The power supply section of this invention provides a stable DC power supply to the circuit; the drive section amplifies the drive signal using an active device and drives the power MOSFET; the turn-off section accelerates the discharge of the power MOSFET and applies a negative voltage when the power MOSFET is turned off, ensuring reliable turn-off; the negative voltage generation circuit uses the conduction process of the power MOSFET to charge a given capacitor, which is then connected to the discharge circuit when the MOSFET is turned off; the power conversion section uses the amplified drive signal to precisely control Q9 to achieve power conversion; thus improving power efficiency and enhancing drive quality. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0015] Figure 1 A diagram showing an embodiment of the single-power negative voltage-supply SiC-MOS driving circuit structure described in this utility model;

[0016] Figure 2 This is a diagram of an embodiment of the single-power negative voltage-supply SiC-MOS driving circuit architecture described in this utility model. Detailed Implementation

[0017] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0018] like Figures 1-2 As shown, this utility model provides a single-supply negative voltage powered SiC-MOS driving circuit, comprising: To at least partially solve the above-mentioned problems, this utility model provides a single-supply negative voltage powered SiC-MOS driving circuit, comprising:

[0019] The circuit consists of a power supply unit 1, a drive unit 2, a shutdown unit 3, a negative voltage generating circuit 4, and a power conversion circuit 5. The power supply unit 1 is connected to the drive unit 2, the negative voltage generating circuit 4, and the single power supply positive terminal VDD. The drive unit 2 is connected to the shutdown unit 3 and the power conversion circuit 5. The shutdown unit 3 is connected to the drive unit 2, the negative voltage generating circuit 4, and the power conversion circuit 5. The negative voltage generating circuit 4 is connected to the power supply unit 1, the drive unit 2, the shutdown unit 3, the single power supply positive terminal VDD, and the power conversion circuit 5.

[0020] The principle and effects of the above technical solution are as follows: it can provide a stable DC power supply for the circuit; in the driving section, the active device amplifies the driving signal and drives the power MOSFET; in the turn-off section, when the power MOSFET is turned off, the active device accelerates the discharge and connects to the negative voltage to ensure reliable turn-off; in the negative voltage generation circuit section, the given capacitor is charged by the conduction process of the power MOSFET and connected to the discharge circuit when turned off; in the power conversion section, the amplified driving signal precisely controls Q9 to achieve power conversion; it improves power efficiency and enhances driving quality.

[0021] In one embodiment, the power supply unit 1 includes: a capacitor C2 and an external terminal; the positive terminal of the capacitor C2 is connected in parallel to the positive terminal of the single power supply VDD, the collector of the transistor Q3 of the driving unit 2, and one end of the resistor R5 of the negative voltage generation circuit 4; the negative terminal of the capacitor C2 is connected to the external terminal.

[0022] The principle and effect of the above technical solution are as follows: the positive terminal of capacitor C2 is connected in parallel to the positive terminal of the single power supply VDD, the collector of transistor Q3 of drive unit 2, and one end of resistor R5 of negative voltage generation circuit 4; the negative terminal of capacitor C2 is connected to the external terminal; and a stable DC power supply is provided for the entire circuit through capacitor C2.

[0023] In one embodiment, the driving unit 2 includes: a transistor Q3 and a resistor R7; the base of transistor Q3 is connected to the first base voltage terminal Vg1; the collector of transistor Q3 is connected to the positive terminal of capacitor C2, the positive terminal of the single power supply VDD, and one end of resistor R5 of the negative voltage generation circuit 4; the emitter of transistor Q3 is connected to one end of resistor R7; the other end of resistor R7 is connected to one end of resistor R8 of the turn-off unit 3 and the gate G of SiC-MOS transistor Q9 of the power conversion circuit 5.

[0024] The principle and effect of the above technical solution are as follows: the base of transistor Q3 is connected to the first base voltage terminal Vg1; the collector of transistor Q3 is connected to the positive terminal of capacitor C2, the positive terminal of the single power supply VDD, and one end of resistor R5 of the negative voltage generation circuit 4; the emitter of transistor Q3 is connected to one end of resistor R7; the other end of resistor R7 is connected to one end of resistor R8 of the turn-off unit 3 and the gate G of SiC-MOS transistor Q9 in the power conversion circuit 5; providing the gate G voltage Vgs; amplifying the G1 signal and driving Q9 to conduct; resistor R7 acts as a current limiter.

[0025] In one embodiment, the shutdown unit 3 includes:

[0026] Transistor Q10, resistor R8 and external terminals; collector of transistor Q10 connected to one end of resistor R8; base of transistor Q10 connected to the second base voltage terminal Vg2; collector of transistor Q10 connected to the other end of resistor R8; emitter of transistor Q10 connected to one end of capacitor C1 of negative voltage generating circuit 4, the positive terminal of diode Z2 and the emitter of transistor Q11 in parallel external terminals.

[0027] The principle and effect of the above technical solution are as follows: the collector of transistor Q10 is connected to one end of resistor R8; the base of transistor Q10 is connected to the second base voltage terminal Vg2; the collector of transistor Q10 is connected to the other end of resistor R8; the emitter of transistor Q10 is connected to one end of capacitor C1 of negative voltage generation circuit 4, the positive terminal of diode Z2, and the emitter of transistor Q11 in parallel external connection; one end of R8 is connected to the gate of Q9, and the other end is connected to the collector of Q10; the emitter of Q10 is at ground level; when VG2 is high level, Q10 conducts and the negative voltage connected to C1 quickly pulls down the VGS level of Q9, achieving the purpose of rapid turn-off.

[0028] In one embodiment, the negative voltage generating circuit 4 includes: resistor R5, resistor R6, capacitor C1, diode Z2, and transistor Q11; the other end of resistor R5 is connected in parallel to one end of resistor R6, the other end of capacitor C1, the negative terminal of diode Z2, the source S of SiC-MOS transistor Q9 of power conversion circuit 5, and one end of resistor R1; the other end of resistor R6 is connected to the collector of transistor Q11; the base of transistor Q11 is connected to the third base voltage terminal Vg3.

[0029] The principle and effect of the above technical solution are as follows: The other end of resistor R5 is connected in parallel to one end of resistor R6, the other end of capacitor C1, the negative terminal of diode Z2, the source S of SiC-MOS transistor Q9 in power conversion circuit 5, and one end of resistor R1; the other end of resistor R6 is connected to the collector of transistor Q11; the base of transistor Q11 is connected to the third base voltage terminal Vg3; C1 and Z2 are connected in parallel, with one end grounded and the other end connected to one end of R5. R6 and Q11 are connected in series and then in parallel with C1, with the emitter of Q11 grounded, and the other end of R6 connected to R5. The other end of R5 is connected to the positive terminal of C2; this is used to generate a negative voltage.

[0030] In one embodiment, the power conversion circuit 5 includes:

[0031] The circuit consists of inductor L2-D, SiC-MOS transistor Q9, and resistor R1. One end of inductor L2-D is connected to the voltage bus VBUS. The other end of inductor L2-D is connected to the drain (D) of SiC-MOS transistor Q9. The source (S) of SiC-MOS transistor Q9 is connected to one end of resistor R1, the other end of resistor R5, the other end of capacitor C1, the negative terminal of diode Z2, and one end of resistor R6. The gate (G) of SiC-MOS transistor Q9 is connected to the other end of resistor R7 and one end of resistor R8. The other end of resistor R1 is grounded.

[0032] The principle and effect of the above technical solution are as follows: one end of inductor L2-D is connected to the voltage bus VBUS; the other end of inductor L2-D is connected to the drain D of SiC-MOS transistor Q9; the source S of SiC-MOS transistor Q9 is connected to one end of resistor R1, the other end of resistor R5, the other end of capacitor C1, the negative terminal of diode Z2, and one end of resistor R6; the gate G of SiC-MOS transistor Q9 is connected to the other end of resistor R7 and one end of resistor R8; the other end of resistor R1 is grounded; for power conversion, the gate of Q9 is connected to the parallel terminal of drive resistor R7 and discharge resistor R8, the drain of Q9 is connected to one end of power transformer, the other end of transformer is connected to the voltage bus, the source of Q9 is connected to one end of sampling resistor, and the other end of sampling resistor is grounded; this improves power efficiency and enhances drive quality.

[0033] This utility model only improves the hardware structure of the system. As for the methods and software programs involved in the operation of the system, those skilled in the art can design them themselves based on the principles and functions proposed in this utility model and in combination with existing technology. The technical solution proposed in this utility model does not improve any methods or software programs.

[0034] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A single-power negative voltage-supply SiC-MOS driving circuit, characterized in that, include: The power supply unit (1), drive unit (2), shutdown unit (3), negative voltage generating circuit (4), and power conversion circuit (5) are connected. The power supply unit (1) is connected to the drive unit (2), negative voltage generating circuit (4), and single power supply positive terminal VDD. The drive unit (2) is connected to the shutdown unit (3) and power conversion circuit (5). The shutdown unit (3) is connected to the drive unit (2), negative voltage generating circuit (4), and power conversion circuit (5). The negative voltage generating circuit (4) is connected to the power supply unit (1), drive unit (2), shutdown unit (3), single power supply positive terminal VDD, and power conversion circuit (5).

2. The single-power negative voltage-supply SiC-MOS driving circuit according to claim 1, characterized in that, The power supply unit (1) includes: capacitor C2 and external terminals; the positive terminal of capacitor C2 is connected in parallel to the positive terminal of the single power supply VDD, the collector of transistor Q3 of the drive unit (2), and one end of resistor R5 of the negative voltage generation circuit (4); the negative terminal of capacitor C2 is connected to the external terminals.

3. The single-power negative voltage-supply SiC-MOS driving circuit according to claim 1, characterized in that, The driving unit (2) includes: transistor Q3 and resistor R7; the base of transistor Q3 is connected to the first base voltage terminal Vg1; the collector of transistor Q3 is connected to the positive terminal of capacitor C2 and the positive terminal of single power supply VDD and one end of resistor R5 of the negative voltage generation circuit (4); the emitter of transistor Q3 is connected to one end of resistor R7; the other end of resistor R7 is connected to one end of resistor R8 of the turn-off unit (3) and the gate G of SiC-MOS transistor Q9 of the power conversion circuit (5).

4. The single-power negative voltage-supply SiC-MOS driving circuit according to claim 1, characterized in that, The shutdown unit (3) includes: transistor Q10, resistor R8 and external terminals; the collector of transistor Q10 is connected to one end of resistor R8; the base of transistor Q10 is connected to the second base voltage terminal Vg2; the collector of transistor Q10 is connected to the other end of resistor R8; the emitter of transistor Q10 is connected to one end of capacitor C1 of the negative voltage generating circuit (4), the positive terminal of diode Z2 and the emitter of transistor Q11 in parallel to the external terminals.

5. The single-power negative voltage-supply SiC-MOS driving circuit according to claim 1, characterized in that, The negative voltage generating circuit (4) includes: resistor R5, resistor R6, capacitor C1, diode Z2 and transistor Q11; the other end of resistor R5 is connected in parallel to one end of resistor R6, the other end of capacitor C1, the negative terminal of diode Z2 and the source S of SIC-MOS transistor Q9 of power conversion circuit (5) and one end of resistor R1; the other end of resistor R6 is connected to the collector of transistor Q11; the base of transistor Q11 is connected to the third base voltage terminal Vg3.

6. The single-power negative voltage-supply SiC-MOS driving circuit according to claim 1, characterized in that, The power conversion circuit (5) includes: The circuit consists of inductor L2-D, SiC-MOS transistor Q9, and resistor R1. One end of inductor L2-D is connected to the voltage bus VBUS. The other end of inductor L2-D is connected to the drain (D) of SiC-MOS transistor Q9. The source (S) of SiC-MOS transistor Q9 is connected to one end of resistor R1, the other end of resistor R5, the other end of capacitor C1, the negative terminal of diode Z2, and one end of resistor R6. The gate (G) of SiC-MOS transistor Q9 is connected to the other end of resistor R7 and one end of resistor R8. The other end of resistor R1 is grounded.

Images