Switched-bus based resonant switched-capacitor converter architecture

Abstract

A cascaded converter architecture comprising a pure switched-capacitor (SC) stage and a resonant SC stage. Multiple switching buses are utilized to connect the first-stage SC converter with second-stage multi-phase resonant SC converters. The flying capacitors of both stages are resonant with the output inductors, so the charge distribution loss is eliminated. Zero-current switching is realized by adjusting the duty ratio and switching frequency. By using the intermediate switching bus, the number of switches can be reduced, and the intermediate bus capacitor is not required; thereby greatly reducing component count and cost while improving power density. Numerous implementation variations are described by way of example and not limitation.