Driving circuit

Abstract

The invention relates to a driving circuit. The driving circuit comprises a protection module connected with a gate pole of a device to be connected, and a voltage regulation module connected between the protection module and the gate pole, the protection module comprises a Schottky diode, a capacitor and a first resistor which are connected in parallel; the voltage regulation module comprises a voltage stabilizing diode, a second resistor, a third resistor, a first node and a second node; the third resistor is connected between the anode of the voltage stabilizing diode and the second node; the second node is connected with the source electrode of the device; the first node is connected with the gate pole; the second resistor is connected between the first node and the second node; wherein when the driving signal is high, the voltage stabilizing diode clamps the gate voltage; after the capacitor is charged, the second resistor divides the voltage, and the voltage stabilizing diode clamps the voltage of the second resistor; and when the signal is low, the voltage at the cathode end of the Schottky diode is reduced, and the Zener diode and the third resistor discharge to form a negative voltage turn-off device. According to the invention, the problem of mis-opening is solved, and the complexity and cost of circuit design are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to a driving circuit. Background Art

[0002] With the rapid development of power electronics technology, drive circuits play an increasingly important role in many fields. These fields include power management, electric vehicles, industrial automation, consumer electronics, communication equipment, home appliances, robotics, and medical equipment. In the field of power management, such as switching power supplies (SMPS), uninterruptible power supplies (UPS), and battery management systems, drive circuits are used to control power conversion and improve overall efficiency. In the field of electric vehicles, drive circuits are responsible for motor control systems and manage the starting, acceleration, and braking processes of motors. In addition, in the fields of industrial automation, consumer electronics, communication equipment, home appliances, robotics, and medical equipment, drive circuits also play a key role, such as precise control of motion and position, control of power output and signal processing, enhancement of signal strength and quality, motor control and function management, control of robot actions and reactions, and control of sensors and actuators in medical instruments.

[0003] At present, gallium nitride (GaN) devices on the market are favored for their high frequency characteristics and high efficiency. However, the driver output voltage of these devices is usually around 6V. In order to adapt to higher voltage application requirements, additional voltage conversion circuits must be added to the circuit design to convert the input high voltage into the voltage required by the gallium nitride device, which not only increases the cost, but also increases the complexity of the circuit design. In addition, due to the characteristics of high voltage change rate (dv / dt) of gallium nitride devices, Miller oscillation may cause false turn-on problems in actual applications, and negative voltage is often required to achieve shutdown, which requires the addition of additional negative voltage generation circuits to the circuit, further increasing the complexity of the circuit.

[0004] At the same time, silicon carbide (SiC) devices have attracted attention in the field of power electronics due to their high temperature stability and high voltage resistance characteristics. The drivers of such devices usually need to provide a positive voltage of 15V~18V when turned on, and a negative voltage of about -4V when turned off. This requires the power supply circuit of the driver to be able to generate two voltages, one for the positive 18V and one for -4V. In contrast, the driving voltage of traditional silicon metal oxide semiconductor field effect transistors (MOS tubes) or insulated gate bipolar transistors (IGBTs) is usually 15V, and the turn-off voltage is 0V, so the driving circuit is relatively simple and only requires a 15V voltage supply. In the process of transitioning from silicon MOS tubes or IGBTs to silicon carbide devices, although it is relatively easy to achieve positive voltage drive, generating the negative voltage required for shutdown requires a lot of adjustments to the circuit, which undoubtedly increases the complexity and cost of circuit design. Summary of the invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the false turn-on caused by Miller oscillation due to high dv / dt in the prior art, as well as the circuit design complexity and cost increase caused by voltage conversion and negative voltage requirements, thereby proposing a driving circuit.

[0006] In a first aspect, in order to solve the above technical problems, the present invention provides a driving circuit, comprising: a protection module, a voltage regulating module and a device to be connected; The protection module is connected to the gate of the device to be connected; the protection module includes a Schottky diode, a capacitor and a first resistor; the Schottky diode is connected in parallel with the capacitor and the first resistor; The voltage regulating module is connected between the protection module and the gate, and includes a voltage regulator diode, a second resistor, a third resistor, a first node, and a second node; the anode of the voltage regulator diode is connected to one end of the third resistor; the other end of the third resistor is connected to the second node; the second node is connected to the source of the device to be connected; the first node is connected to the gate; the second resistor is connected between the first node and the second node; Among them, when the driving signal is high, the first resistor is short-circuited, and the Zener diode clamps the voltage of the gate; when the capacitor is charged, the second resistor and the first resistor form a voltage divider, and the Zener diode clamps the voltage on the second resistor; when the driving signal is low, the cathode terminal voltage of the Schottky diode becomes low, and the Zener diode and the third resistor discharge, forming a negative voltage to turn off the device to be connected.

[0007] In one embodiment of the present invention, the device to be connected is a gallium nitride device. When the driving signal is 0V, the displacement current generates a first voltage on the gate through the parasitic capacitance of the gallium nitride device, and the Schottky diode is used to discharge the first voltage; the displacement current is caused by the rate of change of the electric field strength with time.

[0008] In one embodiment of the present invention, when the device to be connected is a gallium nitride device, the voltage regulator diode and the third resistor are discharged to a specified value.

[0009] In one embodiment of the present invention, the driving signal is a driving signal of a silicon MOS tube.

[0010] In a second aspect, in order to solve the above technical problem, the present invention provides a driving circuit, including: a protection module, a voltage regulation module and a device to be connected; The protection module is connected to the gate of the device to be connected; the protection module includes a Schottky diode, a capacitor and a voltage regulator diode; the Schottky diode is connected in parallel with the capacitor and the voltage regulator diode; The voltage regulating module is connected between the protection module and the gate; the voltage regulating module includes a second resistor, a first node and a second node; the second resistor is connected between the first node and the second node; the second node is connected to the source of the device to be connected; the first node is connected to the gate; Among them, when the driving signal is high, the capacitor is charged and the Zener diode clamps the voltage of the capacitor; when the charging of the capacitor is completed, the voltage of the capacitor is equal to the voltage clamped by the Zener diode; when the driving signal is low, the cathode terminal voltage of the Schottky diode becomes low, forming a negative voltage to shut down the device to be connected.

[0011] In one embodiment of the present invention, the device to be connected is a silicon carbide device, and when the drive signal is 0V, the Schottky diode is used to discharge a second voltage, and the second voltage is generated on the gate by a displacement current through the parasitic capacitance of the silicon carbide device, and the displacement current is caused by the rate of change of the electric field strength with time.

[0012] In a third aspect, in order to solve the above technical problem, the present invention provides a driving device for a gallium nitride device, comprising the above driving circuit.

[0013] In a fourth aspect, in order to solve the above-mentioned technical problem, the present invention provides a driving device for a silicon carbide device, comprising the above-mentioned driving circuit.

[0014] In a fifth aspect, in order to solve the above-mentioned technical problem, the present invention provides a circuit converter, including a driving device of a gallium nitride device or a driving device of a silicon carbide device as mentioned above.

[0015] In a sixth aspect, in order to solve the above-mentioned technical problem, the present invention provides a driving circuit, including the above-mentioned circuit converter.

[0016] The above technical solution of the present invention has the following beneficial effects compared with the prior art: (1) A driving circuit described in the present invention includes a protection module and a voltage regulation module, which integrates capacitors, resistors, Schottky diodes and voltage regulator diode electronic components. In the start-up phase of the circuit, the clamping technology of the voltage regulator diode is used to stabilize the forward gate voltage to ensure that the device to be connected can smoothly enter the working state. In the shutdown phase, negative voltage is automatically generated to achieve negative voltage shutdown. This innovative design significantly enhances the safety and reliability of the device to be connected and ensures its robust operation under variable working conditions. At the same time, the design effectively solves the Miller oscillation problem caused by high dv / dt, avoids the risk of false start-up caused by it, and simplifies the circuit design through the built-in negative voltage generation mechanism, reduces the need for external negative voltage sources, thereby reducing overall cost and complexity. In addition, the parallel combination of the capacitor and the first resistor forms a voltage divider, which helps to stabilize the voltage across the Schottky diode when it is turned on, ensuring the reliability of the circuit under various working conditions. This configuration can also improve the input / output impedance matching of the circuit, optimize the signal transmission quality, and provide a certain delay function when necessary to protect the Schottky diode from the influence of rapid voltage changes.

[0017] (2) The driving circuit described in the present invention not only realizes the efficient conversion from silicon MOS driving to gallium nitride driving, but also enhances the stability and reliability of the driving system while reducing costs, bringing users a more optimized performance experience.

[0018] (3) The drive circuit described in the present invention includes a protection module that uses a Schottky diode, a capacitor and a voltage regulator diode in parallel connection, which ensures voltage stability, quick response and comprehensive protection measures while maintaining high circuit efficiency, meeting the stringent requirements of modern electronic equipment for high-performance drive circuits. In addition, by accurately controlling the clamping voltage of the voltage regulator diode, this design provides a simple and reliable method to adjust the negative voltage value when the gate of the connected device is turned off, further improving the reliability and flexibility of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0020] Figure 1 A structural diagram of a driving circuit in a preferred embodiment of the present invention; Figure 2 This is a flow chart of a driving circuit for shutting down a gallium nitride device in a preferred embodiment of the present invention; Figure 3 A schematic diagram of a driving circuit applied to a PFC circuit in a preferred embodiment of the present invention; Figure 4A schematic diagram of a driving circuit applied to a totem pole bridgeless PFC circuit in a preferred embodiment of the present invention; Figure 5 A schematic diagram of a driving circuit applied to an LLC circuit in a preferred embodiment of the present invention; Figure 6 is another structural diagram of a driving circuit in a preferred embodiment of the present invention; Figure 7 The present invention is a flowchart of a driving circuit for shutting down a silicon carbide device in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0022] Example 1: Reference Figure 1 As shown, this embodiment provides a driving circuit, including: a protection module, a voltage regulation module and a device to be connected Q1; A protection module is connected to the gate of the device to be connected Q1; the protection module includes a Schottky diode D1, a capacitor C1 and a first resistor R1; the Schottky diode D1 is connected in parallel with the capacitor C1 and the first resistor R1; A voltage regulating module is connected between the protection module and the gate, and the voltage regulating module includes a voltage regulator diode DZ1, a second resistor R2, a third resistor R3, a first node and a second node; the anode of the voltage regulator diode DZ1 is connected to one end of the third resistor R3; the other end of the third resistor R3 is connected to the second node; the second node is connected to the source of the device to be connected Q1; the first node is connected to the gate; the second resistor R2 is connected between the first node and the second node; Among them, when the driving signal Vdr is high, the first resistor R1 is short-circuited, and the Zener diode DZ1 clamps the voltage of the gate; when the capacitor C1 finishes charging, the second resistor R2 and the first resistor R1 form a voltage divider, and the Zener diode DZ1 clamps the voltage on the second resistor R2; when the driving signal is low, the cathode terminal voltage of the Schottky diode D1 becomes low, and the Zener diode DZ1 and the third resistor R3 discharge, forming a negative voltage to turn off the connected device Q1.

[0023] The present embodiment provides a driving circuit, including a protection module and a voltage regulation module, integrating capacitor C1, resistor, Schottky diode D1 and voltage regulator diode DZ1 electronic components. When the driving signal is high, the voltage regulator diode DZ1 is used to clamp the gate voltage to ensure that the device to be connected Q1 can smoothly enter the working state. When the driving signal is low, a negative voltage is automatically generated to achieve negative voltage shutdown. This innovative design significantly enhances the safety and reliability of the device to be connected Q1 and ensures its robust operation under variable working conditions. At the same time, the design effectively solves the Miller oscillation problem caused by high dv / dt, avoids the risk of false opening caused by it, and simplifies the circuit design through the built-in negative voltage generation mechanism, reduces the need for an external negative voltage source, and thus reduces the overall cost and complexity. In addition, the first resistor R1 and the capacitor C1 can be connected in parallel to form a voltage divider circuit to adjust the voltage flowing through the Schottky diode D1 so that it works in the best state.

[0024] Specifically, the forward voltage drop of the Schottky diode D1 is between 0.15V and 0.45V, which is significantly lower than the 0.6V to 1.7V range of traditional silicon diodes. This feature significantly reduces power loss during forward conduction, effectively improving the overall efficiency of the system. In addition, the Schottky diode D1 has an extremely short reverse recovery time, which enables it to perform well in fast switching applications. The Schottky diode D1 also has the ability to withstand high current density and the characteristics of maintaining low leakage current in the off state, and these properties together enhance the energy efficiency and reliability of the circuit. Therefore, the embodiment of the present invention preferably uses the Schottky diode D1 to discharge energy oscillations caused by parasitic inductance and capacitor C1 in the circuit during switch conversion, effectively suppressing crosstalk problems in the half-bridge circuit.

[0025] Specifically, the capacitor C1 connected in parallel with the Schottky diode D1 not only provides a filtering function, effectively reducing the noise and ripple in the circuit and making the power supply more stable, but also provides instantaneous current when the transient load changes, further suppressing the voltage spike. The parallel combination of the capacitor C1 and the first resistor R1 forms a voltage divider, which helps to stabilize the voltage across the Schottky diode D1 when it is turned on, ensuring the reliability of the circuit under various working conditions. In addition, this configuration can also improve the input / output impedance matching of the circuit, optimize the signal transmission quality, and provide a certain delay function when necessary to protect the Schottky diode D1 from the influence of rapid voltage changes.

[0026] Specifically, the voltage zener diode DZ1 can provide a highly accurate voltage reference point to ensure that the circuit maintains stable performance in the face of power supply fluctuations. In addition, the voltage zener diode DZ1 has a fast response time, low power consumption, and is easy to integrate. For this reason, the embodiment of the present invention preferably uses the voltage zener diode DZ1 to control the negative voltage value when the gate is turned off.

[0027] Furthermore, in the circuit design of the Zener diode DZ1, a third resistor R3 is connected in series to effectively suppress the radiation interference caused by high-frequency charging and discharging. This design strategy not only improves the electromagnetic compatibility (EMC) of the circuit, but also helps to protect the Zener diode DZ1 from high current shocks, thereby enhancing the stability and reliability of the entire circuit.

[0028] Specifically, in the driving circuit provided in this embodiment, the driving signal Vdr may switch between high and low levels during operation. Assuming that the device to be connected Q1 is a gallium nitride device, the operating principle of the circuit when the driving signal Vdr is high or low can be analyzed by referring to Figure 2 . When the drive signal Vdr is high, during the charging stage of the capacitor C1, its charging process is similar to quickly transferring electrical energy to the gate of the gallium nitride Q1 by shorting the first resistor R1. During this process, the voltage regulator diode DZ1 works immediately to clamp and stabilize the gate voltage within the safe voltage range allowed by the gallium nitride Q1. Once the capacitor C1 is fully charged, the circuit enters a steady state. At this time, the first resistor R1 and the second resistor R2 together form a voltage divider network, and the voltage regulator diode DZ1 continues to play its clamping role, ensuring that the voltage flowing through the second resistor R2 is limited to a safe level, thereby maintaining the gate voltage of the gallium nitride Q1 within a safe range. In this stable state, the voltage value maintained on the capacitor C1 is equal to the drive voltage Vdr minus the gate-source turn-on voltage Vgs of the gallium nitride Q1, that is, the voltage on the capacitor C1 is Vdr-Vgs. When the driving signal Vdr is low, the cathode terminal voltage of the Schottky diode D1 is maintained at 0V. According to the voltage continuity principle of the capacitor (i.e., the voltage cannot change suddenly), the gate voltage of the gallium nitride Q1 will therefore present a negative voltage state, and its value is -(Vdr-Vgs), indicating that the voltage of the gate relative to the source is lower than its normal turn-on voltage. Subsequently, through the discharge circuit formed by the voltage stabilizing diode DZ1 and the third resistor R3, the negative voltage on the gate gradually decreases until it stabilizes at a specified value, which is approximately within the range of -0.5V. This negative voltage state effectively realizes the shutdown operation of the gallium nitride Q1, ensuring that the circuit can quickly and stably cut off the current path when needed. Furthermore, when the driving signal Vdr is 0V, if the gallium nitride Q1 faces a rapid voltage change (dv / dt), in this transient process, the displacement current will induce a first voltage on the gate through the parasitic capacitance Cgd (parasitic capacitance can also be called gate-drain capacitance) of the gallium nitride Q1. Among them, the displacement current is caused by the rate of change of the electric field intensity over time. In order to prevent the induced voltage from causing the gallium nitride Q1 to turn on accidentally, the Schottky diode D1 is used to quickly respond and effectively discharge the first voltage on the gate, thereby ensuring that the gallium nitride Q1 can stably remain in the off state and avoid the occurrence of malfunction.

[0029] Reference Figure 3 , which shows a practical application scenario of a driving circuit provided by an embodiment of the present invention in a PFC (power factor correction) circuit. In the figure, VIN represents the input voltage, L1 represents the inductor numbered 1, D2 represents the diode numbered 2, VBUS represents the bus voltage, C2 and CE1 represent capacitors with different numbers, and GND represents the ground wire. For the PFC circuit, the driving circuit of the present invention is used to drive the gallium nitride device Q1. At this time, the driving signal Vdr is the driving signal of the silicon MOS tube, and the driver using silicon MOS can reduce costs. The driving circuit provided cleverly converts the driving signal of the traditional silicon MOS tube into a driving signal suitable for the gallium nitride device Q1, and generates the necessary negative voltage bias to ensure that the gallium nitride device Q1 can achieve a safe and reliable working state while operating with high efficiency. This innovative design not only realizes the efficient conversion of silicon MOS drive to gallium nitride drive, but also enhances the stability and reliability of the system.

[0030] Reference Figure 4 and Figure 5 , which shows the application scenario of the driving circuit provided in this embodiment in a totem pole bridgeless PFC (power factor correction) circuit and LLC (resonant converter). Figure 4 In the figure, HV represents the connected high voltage, D2, D3, and D4 represent diodes with different numbers, C2, C3, and CE2 represent capacitors with different numbers, L2 represents an inductor numbered 2, R4, R5, and R6 are resistors with different numbers, and GND and GND1 represent ground wires with different numbers. Figure 5 In the figure, ACL represents the live wire, ACN represents the neutral wire, and Q3 and Q4 represent the application devices with different numbers in this scenario. In this application scenario, the negative voltage shutdown GaN devices (Q1 and Q2) reduce the design difficulty of the user, that is, the negative voltage production circuit is integrated to reduce the complexity of the circuit. This application scenario not only verifies the high efficiency and stability of the driving circuit, but also further improves the overall performance and efficiency of the related power electronic conversion system. It should be noted that in Figure 1 , Figures 3 to 5 The same symbols have the same meaning and will not be described again. Figures 3 to 5 Although the marking symbols appearing in the description are reflected in the application scenario, they are not the core elements of the embodiment of the present invention, so this embodiment will not elaborate on them in detail.

[0031] It is worth mentioning that the drive circuit provided by the embodiment of the present invention has a high degree of flexibility and adaptability, and can be combined into a variety of circuit forms, including but not limited to the independent use of a single device, the parallel connection of multiple devices to enhance performance, and the application in complex circuit structures such as half-bridges. This diverse combination capability enables the present invention to meet the specific needs of different application scenarios. In terms of application fields, the drive circuit shows a wide range of applicability and can be widely used in a variety of power electronic circuits, such as BUCK, BOOST, flyback, forward, PFC, LLC resonant converters, and motor drive systems. Whether in DC-DC conversion, AC-DC rectification, or efficient energy conversion and management, the drive circuit can play its unique advantages and improve circuit performance and efficiency. In addition, the drive circuit is also compatible with a variety of packaged gallium nitride devices, including but not limited to convenient surface mount packaging and reliable plug-in packaging. This wide compatibility with packaging forms enables the present invention to be easily integrated into various electronic devices, further broadening its scope of application and market potential.

[0032] Embodiment 2: Based on the same inventive concept, this embodiment provides a driving circuit, the principle of solving the problem is similar to that of the driving circuit provided in Embodiment 1, but there are some differences in the specific implementation. Figure 6 As shown, this embodiment provides a driving circuit, including: a protection module, a voltage regulation module and a device to be connected Q1; The protection module is connected to the gate of the device to be connected Q1; the protection module includes a Schottky diode D1, a capacitor C1 and a voltage zener diode DZ1; the Schottky diode D1 is connected in parallel with the capacitor C1 and the voltage zener diode DZ1; A voltage regulating module is connected between the protection module and the gate; the voltage regulating module includes a second resistor R2, a first node and a second node; the second resistor R2 is connected between the first node and the second node; the second node is connected to the source of the device to be connected Q1; and the first node is connected to the gate; Among them, when the driving signal is high, the capacitor C1 is charged and the voltage of the capacitor C1 is clamped by the Zener diode DZ1; when the charging of the capacitor C1 is completed, the voltage of the capacitor C1 is equal to the voltage clamped by the Zener diode DZ1; when the driving signal is low, the cathode terminal voltage of the Schottky diode D1 becomes low, forming a negative voltage to turn off the connected device Q1.

[0033] This embodiment provides a driving circuit, in which the protection module connects the Schottky diode D1, the capacitor C1 and the voltage stabilizing diode DZ1 in parallel, thereby ensuring the stability of the voltage, the rapidity of the response and the comprehensive protection measures while maintaining the high efficiency of the circuit, thus meeting the stringent requirements of modern electronic equipment for high-performance driving circuits. In addition, by accurately controlling the clamping voltage of the voltage stabilizing diode DZ1, this design provides a simple and reliable method to adjust the negative voltage value when the gate of the connected device Q1 is turned off, further improving the reliability and flexibility of the circuit.

[0034] Specifically, the driving circuit provided in this embodiment may face the situation that the driving signal Vdr switches between high and low levels during operation. Assuming that the device to be connected Q1 is a silicon carbide device, the operating principle of the circuit when the driving signal Vdr is high or low can be analyzed by referring to Figure 7 . When the drive signal Vdr is high, the capacitor C1 quickly enters the charging state. During this process, its charging path can be regarded as a short circuit, so that the voltage of the drive signal Vdr is transmitted to the gate of the silicon carbide Q1 almost without attenuation. At the same time, the Zener diode DZ1 plays a voltage clamping role, limiting the voltage of the capacitor C1 and the gate of the silicon carbide Q1 to a safe and stable range, protecting the silicon carbide Q1 from overvoltage damage. After charging is completed, the voltage stored on the capacitor C1 is the voltage value clamped by the Zener diode DZ1. At this time, the gate voltage of the silicon carbide Q1 is Vgs, and the voltage difference across the capacitor C1 can be regarded as the difference between the drive signal Vdr and Vgs, that is, Vdr-Vgs. When the drive signal Vdr is low, the cathode terminal voltage of the diode D1 drops to 0V. Due to the voltage holding characteristic of capacitor C1 (i.e., the voltage cannot change suddenly), the gate voltage of silicon carbide Q1 will present a negative voltage relative to the source, and its value is exactly equal to the voltage maintained after the capacitor C1 is charged, that is, the voltage clamped by the voltage zener diode DZ1, expressed as -(Vdr-Vgs). This negative voltage state ensures that silicon carbide Q1 can be effectively turned off when the drive signal is low, blocking the further flow of current. Furthermore, when the drive signal Vdr is 0V, if silicon carbide Q1 faces a rapid voltage change (dv / dt), during this transient process, the displacement current will induce a second voltage on the gate through the parasitic capacitance Cgd (also known as the gate-drain capacitance) of silicon carbide Q1. In order to prevent this induced voltage from causing silicon carbide Q1 to accidentally turn on, the Schottky diode D1 is designed to respond quickly and effectively discharge the second voltage on the gate, thereby ensuring that silicon carbide Q1 can stably remain in the off state and avoid the occurrence of false operation.

[0035] Embodiment 3: This embodiment provides a driving device for a gallium nitride device, including a driving circuit provided in Embodiment 1.

[0036] Embodiment 4: This embodiment provides a driving device for a silicon carbide device, including a driving circuit provided in Embodiment 2.

[0037] Embodiment 5: This embodiment provides a circuit converter, including a driving device of a gallium nitride device provided in Embodiment 3 or a driving device of a silicon carbide device provided in Embodiment 4.

[0038] Embodiment 6: This embodiment provides a mobile device, including a circuit converter provided in Embodiment 5.

[0039] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A driving circuit, characterized in that: include: Protection module, voltage regulation module and devices to be connected; The protection module is connected to the gate of the device to be connected; the protection module includes a Schottky diode, a capacitor and a first resistor; the Schottky diode is connected in parallel with the capacitor and the first resistor; The voltage regulating module is connected between the protection module and the gate, and includes a voltage regulator diode, a second resistor, a third resistor, a first node, and a second node; the anode of the voltage regulator diode is connected to one end of the third resistor; the other end of the third resistor is connected to the second node; the second node is connected to the source of the device to be connected; the first node is connected to the gate; the second resistor is connected between the first node and the second node; Among them, when the driving signal is high, the first resistor is short-circuited, and the Zener diode clamps the voltage of the gate; when the capacitor is charged, the second resistor and the first resistor form a voltage divider, and the Zener diode clamps the voltage on the second resistor; when the driving signal is low, the cathode terminal voltage of the Schottky diode becomes low, and the Zener diode and the third resistor discharge, forming a negative voltage to turn off the device to be connected.

2. A driving circuit according to claim 1, characterized in that: The device to be connected is a gallium nitride device. When the driving signal is 0V, the displacement current generates a first voltage on the gate through the parasitic capacitance of the gallium nitride device. The Schottky diode is used to discharge the first voltage. The displacement current is caused by the rate of change of the electric field intensity with time.

3. A driving circuit according to claim 1, characterized in that: When the device to be connected is a gallium nitride device, the voltage regulator diode and the third resistor discharge to a specified value.

4. A driving circuit according to claim 1, characterized in that: The driving signal is a driving signal of a silicon MOS tube.

5. A driving circuit, characterized in that: include: Protection module, voltage regulation module and devices to be connected; The protection module is connected to the gate of the device to be connected; the protection module includes a Schottky diode, a capacitor and a voltage regulator diode; the Schottky diode is connected in parallel with the capacitor and the voltage regulator diode; The voltage regulating module is connected between the protection module and the gate; the voltage regulating module includes a second resistor, a first node and a second node; the second resistor is connected between the first node and the second node; the second node is connected to the source of the device to be connected; the first node is connected to the gate; Among them, when the driving signal is high, the capacitor is charged and the Zener diode clamps the voltage of the capacitor; when the charging of the capacitor is completed, the voltage of the capacitor is equal to the voltage clamped by the Zener diode; when the driving signal is low, the cathode terminal voltage of the Schottky diode becomes low, forming a negative voltage to shut down the device to be connected.

6. A driving circuit according to claim 5, characterized in that: The device to be connected is a silicon carbide device. When the driving signal is 0V, the Schottky diode is used to discharge a second voltage. The second voltage is generated on the gate by a displacement current through the parasitic capacitance of the silicon carbide device. The displacement current is caused by the rate of change of the electric field strength with time.

7. A driving device for a gallium nitride device, characterized in that: A driving circuit comprising any one of claims 1 to 4.

8. A driving device for a silicon carbide device, characterized in that: A driving circuit comprising any one of claims 5 to 6.

9. A circuit converter, characterized in that: It comprises a driving device for a gallium nitride device as claimed in claim 7 or a driving device for a silicon carbide device as claimed in claim 8.

10. A mobile device, characterized in that: A circuit converter comprising the circuit converter described in claim 9.

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