Reduced synchronous-rectifier losses in off-line resonant converters using the LCC topology

Resonant converters are becoming popular for off-line applications where high efficiency is sought. In this paper we examine the performance improvements achieved using an LCC topology with a full-bridge synchronous rectifier compared to TDK-lambda´s NV topology (an LLCC topology). A low cost drive scheme is also disclosed for efficient driving of the synchronous rectifiers.