Patent ID: 6181578
Filing Date: 2001-01-30
Classification: H02M,Y02B

Abstract:
A resonant reset forward converter, comprising:a transformer having a primary winding and a secondary winding;a power switch in series with said transformer and coupled to an input power source, said power switch capable of being alternately switched between an on period and an off period such that an ac voltage is generated across said secondary winding in response thereto, said off period including a transformer reset period and a subsequent dead period;an output filter operative to provide a substantially constant dc voltage to an output load;a forward rectifier operative to provide a forward conduction path between said secondary winding and said output filter during said on period;a free-wheeling rectifier operative to provide a conduction path between said secondary winding and said output filter;means for causing said free-wheeling rectifier to be conducting during said reset period;means for maintaining the conduction state of said free-wheeling rectifier during said dead period by maintaining a suitable charge level on the gate of said free-wheeling rectifier; andmeans for switching said free-wheeling rectifier to a non-conducting state at the beginning of a subsequent on period.