Patent ID: 7408328

Claim:
A power supply unit comprising: a switching power regulator comprising: an output electrically coupled to a first side of an inductor, wherein the output is electrically coupled to a load; a capacitor electrically coupled to a second side of the inductor, wherein the second side is opposite the first side; and a controller to reverse a direction of a flow of current through the inductor and discharge energy from the inductor to the capacitor in response to detecting that a voltage level at the output is rising, wherein the controller comprises: a first switch electrically coupled to the inductor and a voltage input; a second switch electrically coupled to the voltage input and the capacitor; a third switch electrically coupled to the capacitor, the inductor and ground; a fourth switch electrically coupled to the capacitor and ground; and a control circuit electrically coupled to the output, the first switch, the second switch, the third switch, and the fourth switch, wherein the capacitor is charged during periods of the duty cycle in which the first switch is open, the second switch is closed, the third switch is closed, and the fourth switch is open.