High-reliability MOSFET drive circuit

Abstract

The invention relates to a drive circuit applied to a power switch tube MOSFET, in particular to a drive circuit of a silicon carbide MOSFET, and belongs to the technical field of drive circuits. The drive circuit aims to solve the problem that when an MOSFET in an existing drive circuit is turned off, the reliability is poor. The drive circuit comprises a PWM control circuit, a drive pulse amplifying circuit, a drive resistor Rg, a first diode D1, a resistor R1, a PNP triode Qoff, a second diode D2 and a capacitor C. According to the drive circuit, the PNP triode Qoff, the resistor R1 and the capacitor C form an MOSFET turn-off circuit; when the MOSFET is turned off quickly, a gate pole positive voltage spike caused by Miller currents is effectively suppressed; meanwhile, a gate pole negative voltage spike can also be suppressed through the second diode D2 and the capacitor C, it is guaranteed that the MOSFET is turned off safely and reliably, and the performance advantages of the silicon carbide MOSFET can be given to full play.

Description

technical field [0001] The invention relates to a driving circuit applied to a MOSFET of a power switch tube, in particular to a driving circuit of a silicon carbide MOSFET, which belongs to the technical field of driving circuits in the discipline of electrical engineering. Background technique [0002] Applications such as aviation, aerospace, and electric vehicles have higher and higher requirements for power electronic converters, and converters are constantly developing in the direction of high efficiency, miniaturization and high reliability. One of the development trends. After decades of research on silicon devices based on silicon semiconductor materials, their performance has approached the theoretical limit and has become one of the main factors limiting the performance of converters. Therefore, new power devices based on silicon carbide semiconductor materials have emerged as the times require. Compared with silicon devices, the new silicon carbide semiconductor...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to overcome the problem of low turn-off reliability of existing MOSFET drive circuits in high-frequency applications, and to provide an active auxiliary turn-off circuit, which can suppress positive and negative voltage spikes that may occur in the gate voltage, It can effectively prevent the failure of the converter caused by the misoperation of the switch tube, improve the reliability of the circuit, provide a guarantee for giving full play to the advantages of silicon carbide MOSFET, and promote the further improvement of the performance of the converter

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