An Improved Resonant Gate Driver for MOSFETs in DC-DC Converters

Abstract

The Resonant Gate Drivers (RGDs) have a key role in increasing switching performance, facilitating the integration of gate drivers with converters and reducing the gate loss of discrete components, such as power Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), Silicon Carbide (SiC) MOSFETs and insulated gate bipolar transistors (IGBTs) at high switching frequencies to promote the integration level of gate drivers with power modules. In this paper, an improved non-complex, and low-cost RGD, with an air core inductor and an adjustable duty ratio in high switching frequencies is proposed for discrete MOSFETs. The RGD that may provide less leakage current proposed in this paper uses MOSFETs, bipolar junction transistors (BJTs), and a few passive components. In addition, another focus is to eliminate the oscillations between gate-source terminals that force the limits of breakdown voltage between drain-source terminals and cause excessive thermal losses and failures on discrete components. The gate driver also includes four stages; the small signal-switching circuit, the signal amplitude-shifting circuit, the B-type push-pull circuit containing transistors connected by the totem pole technique and resonant circuit based on air core inductor. The last stages ensures the controlling of charge- discharge of the input capacitance of the MOSFET and reduces power consumption, thus, the peak voltages during the turn-on stages are also decreased. The power MOSFET with high input capacitance in a DC-DC converter is used to verify the experimental vaidation. In addition, the results of the experimental study, based on switching frequancy and total power consumption, are compared with some other RGDs introduced in the literature.