Patent ID: 7432664

Claim:
A circuit for powering a high intensity discharge (HID) lamp, the circuit comprising: first and second input terminals for receiving a source of substantially direct current (DC) voltage; first and second output terminals adapted for coupling to an HID lamp; a first inverter switch coupled between the first input terminal and a first node; a second inverter switch coupled between the first node and circuit ground, wherein circuit ground is coupled to the second input terminal; a buck inductor coupled between the first node and a second node; a first buck capacitor coupled between the first input terminal and the second node; a second buck capacitor coupled between the second node and circuit ground; a first low-side capacitor coupled between the first input terminal and a third node, wherein the third node is coupled to the second output terminal; a second low-side capacitor coupled between the third node and circuit ground; an ignitor coupled between the second node and the first output terminal; and wherein the circuit is characterized by further comprising: a diode subcircuit coupled between the first and second input terminals; and a secondary winding that is magnetically coupled to the buck inductor, wherein the secondary winding is coupled between the diode subcircuit and the third node.