Abstract：To further improve the efficiency of a flyback converter, a novel flyback converter with synchronous rectifier (SR) and its related control scheme are proposed in this paper. Due to the bidirectional current flow capability of the SR, the transformer leakage energy can be recycled by paralleling lossless snubber capacitor between the drain and source of the primary switch, and the primary side switch can also be soft switched. Therefore, the switching loss and the leakage energy loss can be reduced, and high conversion efficiency can be achieved in the whole load range. The experimental results from a 16V/4A prototype verify the effectiveness of the proposed method.
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2014, Vol. 29 
