Patent ID: 9577546
Date: 2017-02-21
CPC Classifications: H02M,Y02B

Claim:
1. A power converter comprising: a first AC input terminal coupled between first and second synchronous rectifier switching elements, the first and second synchronous rectifier switching elements coupled across first and second DC output terminals; a second AC input terminal coupled between third and fourth synchronous rectifier switching elements, the third and fourth synchronous rectifier switching elements coupled across the first and second DC output terminals; an AC input sensing circuit; a DC level shifting circuit effective to apply a DC offset to an AC input signal received via the sensing circuit; and switching control circuitry coupled to receive the AC input signal with the DC offset and comprising a second comparator circuit effective to compare the AC input signal with the DC offset to a second reference voltage and to generate a second control signal for turning on the second and third switching elements when the input signal is less than the second reference voltage.