Robust MOSFET Driver for RF, Class-D Inverters

The gate driver presented here allows the operation of a half-bridge resonant inverter at 13.56 MHz using standard package switching devices. Similar to other sinusoidal drivers, it inherently provides dead time between conduction of the power devices and consumes relatively low power with respect to square wave drivers. One advantage of the presented topology is that it exhibits high tolerance of the Miller effect of the driven devices and can therefore drive high capacitance, low-cost MOSFETs at radio frequencies. Another advantage of this driver is that it uses modestly rated devices. The concepts developed in this paper are demonstrated with two 13.56 MHz, 300 W/500 W prototype inverters with efficiencies above 85%.