Patent ID: 7145786
Filing Date: 2006-12-05
Classification: H01F,H02J,H02M,Y02B

Abstract:
1. A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising: providing a transformer; forming a resonant circuit including the transformer and having a characteristic resonant frequency and period; providing output circuitry connected to the transformer for delivering a rectified output voltage to the load; providing a first pair of primary switches connected in series and a second pair of primary switches connected in series, the first and second pairs connected to drive the resonant circuit; and providing a switch controller to operate the first and second pair of primary switches in opposition of phase in a series of converter operating cycles at resonance or frequency modulated near resonance; and arranging the resonant circuit and primary switches symmetrically to reduce common-mode noise.