A 15-V, 40-kHz class-D gate driver IC with 62% energy recycling rate

This paper presents a new type of gate driver IC that can significantly reduce the gate switching loss by leveraging high-speed and low-power operation of custom integrated circuits. The gate driver itself works as a mini bidirectional buck converter, which charges and discharges the gate terminal of a power device (e.g. IGBT) by feeding a chain of short pulses whose widths gradually increase or decrease into an LC filter. A set of circuit techniques to minimize the energy consumption in generating these pulses at the required frequency of up to 50-MHz and duty-cycle resolution of 5% is presented. A prototype IC fabricated in a 0.25-μm HV CMOS demonstrates 27.8-mW power consumption or equivalently 62% energy recycling while switching a 120-nC IGBT at 40-kHz and 15-V.