Patent ID: 6980441
Filing Date: 2005-12-27
Classification: H02M,Y02B

Abstract:
1. A forward converter, comprising: a transformer having a primary winding and a secondary winding; a power switch connected 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 as a function of a PWM signal comprising pulses generated by a PWM circuit and such that an AC voltage is generated across said secondary winding in response thereto; an output filter operative to provide a substantially constant DC voltage to an output load; a forward rectifier having a control input and being operative to provide a forward conduction path between said secondary winding and said output filter during said on period; a free-wheeling synchronous rectifier having a control input and being operative to provide a second conduction path for maintaining current to said output filter during said off period; and a control circuit coupled to said control input of said free-wheeling synchronous rectifier for controlling the state thereof, said control circuit receiving a clock signal varying between an upper voltage and a lower voltage and having a frequency equal to or greater than said PWM signal, comprising: