Flyback-Based Multiple Output dc-dc Converter with Independent Voltage Regulation

Abstract: This paper proposes a new single input multiple output power supply by integrating a flyback converter and several buck converters. The flyback converter works as the main regulator, and the buck converters provide series voltage compensation with the aim of tight regulation. A time multiplexing switching scheme is proposed to deliver multiple output voltage levels via a two winding transformer and to eliminate the cross regulation between output channels. This configuration reduces the size of flyback transformer and filter capacitors, and consequently improves the overall form factor. A detailed steady state analysis is conducted on the circuit to obtain the design criteria. A three output channel power supply is designed and the effectiveness of the proposed configuration is validated via simulation with a MATLAB/Simscape model. Simulation results also demonstrate satisfactory transient response to load changes.