Sneak circuit analysis for a DCM flyback DC-DC converter considering parasitic parameters

摘要

Sneak circuit phenomena caused by parasitic parameters are found in a DCM flyback converter. The operating principle and the condition of the sneak circuit are derived. It is found that the voltage stress of the switch can be reduced by sneak circuit analysis. Thus the switching loss is reduced. Moreover, the effects of each parasitic parameter on the voltage spike of the switch are analyzed in detail, which advanced the guidelines for safer design. The DS pulse of the switch can be eliminated by selecting optimal circuit parameters. Simulation results verified the theoretical analysis.