Design and analysis of a fully-integrated planar transformer for LCLC resonant converters

The isolated LCLC resonant converter needs five discrete passive components including two capacitors, two inductors and a transformer. In this paper, to cut down the number of components of this converter, a new design for a high-frequency transformer is proposed which integrates all the five magnetic and capacitive components in only a single magnetic device. The series capacitor and inductor are integrated into the primary winding and the parallel capacitor and inductor are integrated into the secondary winding. The design guideline for this transformer is presented in detail and theoretical analysis is confirmed by simulation results.