A switching type power converter circuit includes a step-down converter circuit, a DC/AC converter circuit coupled to the step-down converter circuit, and a rectifier circuit coupled to the DC/AC converter circuit. In one embodiment, the DC/AC converter operates with near 50% duty cycle and with substantially zero-voltage, substantially minimum current switching in a resonant mode. An auxiliary step down converter may be added. An AC/DC converter front end with a full-wave bridge, an RF filter, and a power factor correction circuit may also be added.