Voltage regulation in switched-capacitor converters : A problem revisited

Abstract

The paper discusses the possible means of voltage regulation in SC DC-DC converters. The state-of-the-art is reviewed and a brief comparative study is given in view of attainable energy efficiency. Different regulation schemes are discussed. Novel canonical-form SC circuits are proposed based on published systematic synthesis procedure. Practical implications, illustrated by several SC converter examples, include savings in the number of components required, the possibilities to construct an arbitrary fractional voltage ratio within theoretical Fibonacci limits, and to construct a voltage inverting converter, all with the use of the unified canonical circuit. Depended on demanded performance such a circuit can operate either as a wide voltage range converter or as a stepping regulator being a pre-converter for another power block. In both cases the circuit constitutes a realization of a tapping DC-DC transformer.