Patent ID: 7012817
Filing Date: 2006-03-14
Classification: H02M,Y02B

Abstract:
1. A converter which comprises: a transformer having a primary winding, a secondary winding and an auxiliary winding; a first switching device for connecting an input voltage to the primary winding of the transformer; an output circuit connected to the secondary winding; a controller; and an integrated active clamp and primary bias circuit including the auxiliary winding and a second switch for providing a bias voltage to the controller to alternately operate the first and second switches between conductive and non-conductive states such that when the first switch is conductive the second switch is nonconducting and power is transferred from the primary winding to the output circuit via the secondary winding and from the auxiliary winding to the controller and, when the first switch is nonconducting, the second switch is conducting to provide voltage clamping of the primary winding of the transformer via the auxiliary winding and the second switch.