A Resonant Gate-Drive Circuit Capable of High-Frequency and High-Efficiency Operation

This paper deals with a new resonant gate-drive circuit for power MOSFETs. The proposed gate-drive circuit is characterized by a resonant inductor connected in series with the gate terminal of the driven MOSFET. The inductor and the input capacitance of the MOSFET form a series resonant circuit, which enables to charge or discharge the gate-to-source input capacitance of the MOSFET without any electric power consumption in theory. Experimental results are shown to verify the viability of the resonant gate-drive circuit. As a result, the proposed resonant gate-drive circuit reduces its power consumption by a factor of ten, compared with a conventional one. A 360-kHz and 1-kW MOSFET inverter driven by the proposed gate-drive circuits exhibits a high efficiency more than 99%, considering the losses in the two main MOSFETs and the two resonant gate-drive circuits.