Strategy and Implementation of Multi-mode Control in Switch-Mode Power Supply

Abstract

In order to reduce the standby power and increase the efficiency of the SMPS (Switch-Mode Power Supply), a multimode control strategy is presented and implemented in this paper. Three different modes are applied in the strategy and the optimization is achieved according to different load. The SMPS can work adaptively in different modes according to variable load. A chip is designed and fabricated on BCD 700 technology and a 12W (12V/1A) laboratory prototype is built in order to verify the proposed strategy. The experimental results have shown that the average efficiency of the proposed SMPS is 84% and the standby power consumption is 90mW, which both meet the requirements of the latest Energy Star specification with margin.