IGBT gate driver IC with full-bridge output stage using a modified standard CMOS process

This paper discusses the benefits of a full-bridge output stage on integrated IGBT gate drive circuits. This full-bridge topology allows obtaining positive and negative gate voltages using a single floating power supply. Short circuit protections have also been integrated, implementing an original soft shutdown process after an IGBT short circuit fault. The monolithic integration is based on an innovative high-voltage CMOS technology for power integrated circuits, using a standard low cost CMOS technology, requiring only one extra processing step. Lateral power N- and P-MOS transistors have been optimized using 2D simulators attending both specific on-resistance and breakdown voltage in order to optimize the full-bridge output stage. The IGBT driver has been experimentally tested, producing ±15 V gate-to-emitter voltage, and supplying the current peaks required by the 600 V IGBT switching processes. The driver characteristic response times are adapted to work at high switching frequency (>25 kHz) with high value of capacitive loads (3.7 nF).