This invention relates to a resonant gate drive circuit for a power
switching device, such as a MOSFET, that uses a center-tapped transformer
to increase the driving gate voltage approximately twice as high as the
supply voltage. The gate capacitance of the power switching device is
charged and discharged by a constant current source, which increases the
switching transition speed of the power switch. The circuit is suitable
for driving a pair of low side switches with 50% duty cycle or less, such
as in a variable frequency resonant converter, push-pull converter, or
the like.