Topology-independent synchronous rectifier commutation circuit

摘要

The use of synchronous rectifier MOSFETs in the secondary circuit of AC/DC converters is made possible in synchronous rectifier unfriendly topologies such as flyback converters by sensing the onset of forward current in the MOSFET drain-source circuit, optionally converting that current information into logic level signals, and using the information or signals to drive the gate of the synchronous rectifier MOSFET.