Resonant gate drive circuit for a power switching device in a high frequency power converter

Abstract

A resonant gate drive circuit for a power switching device, having a gate-emitter capacitance, is adapted for use with a high frequency power converter. The resonant gate drive circuit comprises a signal input source, a power supply and a resonant inductor. An electrical isolator is connected between the signal input source and a switching node. The electrical isolator is connected to the power supply. A first bidirectional switch is connected between the resonant inductor and the power switching device and includes a first switch control circuit connected to the node to be controlled by a signal from the signal input source. A second bidirectional switch is connected between the power supply and the power switching device and includes a second switch control circuit connected to the node to be controlled by the signal from the input source. The first and second control circuits are adapted to control the first bidirectional switch to provide a first charge path during a resonant period from the resonant inductor to the gate-emitter capacitance defining a quick resonant charge path and to control the second bidirectional switch to provide a second charge path defining a voltage equalization charge path subsequent to the resonant period.