Design of step up and down Bi-directional switched capacitor DC-DC converter

This paper presents the design technique to implement a DC-DC converter that can convert input voltage with step-up or step-down, and bi-directional power flow. The conversion ratio and power efficiency of the converter can be specified by circuit structure, which has capacitors connected in parallel or series configuration. The conversion ratios of step up and step down are 2x, 3x, 4x,... and 1/2x, 1/3x, 1/4x,..., respectively. The direction of power flow can be controlled by state of input and output switches. SPICE simulation results show that output voltage and power efficiency of the proposed converter agree well with theoretical values. © 2012 ICIC International.