Patent ID: 6577518
Filing Date: 2003-06-10
Classification: H02M,Y02B

Abstract:
A switching power converter, comprising:a switching transformer having a primary winding and a secondary winding, the secondary winding having a first and second voltage nodes across which a winding voltage having a phase and a variable duty cycle is impressed; a first synchronous rectifier transistor switch coupled from the first voltage node to a common node; a second synchronous rectifier transistor coupled from the second voltage node to the common node; and a gate driving circuit directly connected to the first and second voltage nodes, a gate driver circuit being operable to produce first and second drive signals to the respective gates of the first and second synchronous rectifier transistors based upon the winding voltage, so as to maintain both transistors on at the same time for a short period such that currents through the transistor switches dissipate through the transistors rather than through body diodes of the transistors to thereby reduce conduction losses.