GENERAL SELF-CONTROLLED SYNCHRONOUS TRANSMISSION SCHEME FOR SYNCHRONOUS RECTIFIERS WITH AN ANCHORABLE GATE

摘要

A self-driven synchronous rectifier circuit having synchronous rectifiers with floating gates for a power converter or signal transformer. The circuit comprises a transformer (49, 70) having a secondary winding with a first and second terminal, a first synchronous rectifier (SQ1) coupled to the first transformer secondary winding first terminal and having a control terminal floating relative to ground and a first drive circuit coupled to the first synchronous rectifier floating control terminal and controlling the first synchronous rectifier. A first control signal is coupled to the first drive circuit, where the first control signal controls the first drive circuit as a function of a polarity reversal of a voltage across the first transformer (49, 70). A second synchronous rectifier (SQ2) is coupled to the first transformer secondary winding second terminal and has a control terminal floating relative to ground. A second drive circuit is coupled to the second synchronous rectifier floating control terminal and controls the second synchronous rectifier. A second control signal is coupled to the second drive circuit, where the second control signal controls the second drive circuit as a function of a polarity reversal of a voltage across the first transformer (49, 70).