High-Efficiency Slim Adapter With Low-Profile Transformer Structure

Abstract

This paper presents the implementation of a high-efficiency slim adapter using an LLC resonant converter. A new structure of the slim-type transformer is proposed, which is composed of copper wire as the primary winding and printed-circuit-board winding on the outer layer as the secondary winding. The proposed structure is suitable for a slim and high-efficiency converter because it has advantages of easy utilization and wide conductive cross-sectional area. In addition, the voltage-doubler rectifier is applied to the secondary side due to its simple structure of secondary winding, and a CLC filter is adopted to reduce the output filter size. The validity of this study is confirmed by the experimental results from an 85-W prototype.