Quad Gate-Driver Controller with Start-Up and Shutdown for Cascaded Resonant Switched-Capacitor Converter

A modular quad gate-driver and controller chip for use with cascaded 2:1 switched-capacitor (SC) resonant dc-dc converters is presented. The solution integrates the controller, level-shifters, active bootstrap and gate-drivers along with start-up and shutdown assist peripherals for standalone operation of a hybrid SC cell with four power switches. Significant size reduction of auxiliary components is demonstrated, yielding improved efficiency and power density. The modularity of the approach is demonstrated with a three-stage resonant converter prototype with 8:1 conversion ratio from 48V DC bus to 6V DC intermediate bus, with peak efficiency of 97.8% and 30A load capability. The quad gate-driver is integrated in a 180nm BCD process with external bootstrap capacitors.