Patent ID: 8780586

Claim:
An apparatus to convert alternating current (AC) line power to direct current (DC) power, comprising: a rectifier to receive a high voltage AC line power input and to output a full wave rectified high voltage DC; a voltage-reducing voltage regulator coupled to the rectifier to receive the full wave rectified high voltage DC and to provide an intermediate voltage DC capped by a preset voltage threshold corresponding to the intermediate voltage DC, wherein the regulator is to supply the intermediate voltage DC by gating the full wave rectified high voltage DC at the preset voltage threshold; and a voltage-reducing switching DC-DC converter directly coupled to the voltage-reducing regulator to receive the intermediate voltage DC provided by the voltage-reducing regulator, the voltage-reducing DC-DC converter to step down and smooth out the intermediate voltage DC to a desired high current, low voltage DC output, the voltage-reducing regulator being coupled between the rectifier and the voltage-reducing DC-DC converter to isolate the full wave rectified high voltage DC from the voltage-reducing DC-DC converter, wherein the voltage-reducing regulator comprises a gating component to gate the high voltage DC by turning on at a zero crossing level and turning off when the high voltage DC exceeds the preset voltage threshold and remain off after the high voltage DC exceeds the preset voltage threshold and until a next zero crossing level.