Research on the Reverse Conduction of Synchronous Rectifiers

Research on the reverse current phenomenon in synchronous rectifiers (SRs) is presented in this paper. For loss reduction, the SRs composed of metal-oxide-semiconductor field-effect transistors (MOSFETs) have recently been employed to replace the conventional rectifiers with diodes in low-voltage and high-current applications. Because the MOSFETs in the SRs are used as bidirectional switches, reverse current flow will probably occur. The reverse current phenomenon will cause undesired power loss. To clarify the effects of the reverse current on the forward converter with an SR, both the experiment and the analysis are performed. Furthermore, the concepts and methods for dealing with this phenomenon are clearly described in this paper.