High efficiency slim adapter with low profile transformer structure

This paper presents the implementation of high efficiency slim adapter using LLC resonant converter. A new structure of slim-type transformer is proposed, which is composed of copper wire as primary winding and printed circuit-board(PCB)-winding on the outer layer as secondary winding. The proposed structure is suitable for 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 CLC filter is adopted to reduce output filter size. The validity of this study is confirmed by the experimental results from an 85W prototype.