A novel high‐frequency floating resonant gate driver with reduced gate driving loss

Abstract

Conventional resistive gate driving circuits suffer from significant recovery gate driving losses, especially at MHz ranges. The increasing gate driving losses brought by high switching frequency place a limitation to the high power density converter design. This paper proposes a novel floating resonant gate driver which maintains high efficiency at several megahertz operating frequency. The gate loss reduction is achieved by adopting a resonant process with driving power recycling. Part of the gate driving power can be recycled to a gate driving capacitor in the gate driving loop during charging and discharging. The proposed gate driver merges the merits of fast switching speed and low gate driving losses. A prototype of LLC power converter with the proposed floating resonant gate driver operating at 3.5 MHz is implemented. According to the experimental verification, the proposed gate driver realized a driving loss reduction by 70% and theoretical analysis is in good agreement with experimental results.