Patent ID: 7139179

Claim:
A switched mode power converter, comprising: a transformer having a primary winding, a secondary winding, and a bias winding; a primary side power switch coupled to said primary winding and being adapted to periodically apply an input voltage to said primary winding; an output filter operatively coupled to said secondary winding to provide an output voltage and output current; a forward synchronous rectification device operatively coupled in series between said secondary winding and said output filter; a free-wheeling synchronous rectification device operatively coupled in shunt with said secondary winding and said output filter; and a control circuit coupled to said bias winding and said forward and free-wheeling synchronous rectification devices, said control circuit including a forward driving device adapted to couple an activation terminal of said forward synchronous rectification device to a first end of said secondary winding and a free-wheeling driving device adapted to couple an activation terminal of said free-wheeling synchronous rectification device to a second end of said secondary winding, said control circuit activating said forward and free-wheeling driving devices responsive to voltage on said bias winding.