Patent ID: 7792166
Filing Date: 2010-09-07
Classification: H01S

Abstract:
1. An apparatus comprising: a first DC-to-DC converter having one or more voltage-step-down circuits, each voltage step-down circuit operatively coupled to apply a duty-cycle-modulated pulse train through an inductor to an output to control a value of a current through a load, wherein there is substantially no capacitance at the first DC-to-DC converter's output; wherein each one of the one or more voltage step-down circuits further includes a first transistor and a second transistor, the first transistor alternately turning substantially on and substantially off and coupled to provide a switched current path for inductor current as controlled by the pulse train, and the second transistor coupled to provide a current path for the inductor that substantially conducts only when the first transistor is off; and wherein the load is connected between a first supply voltage and a first node of the inductor of each one of the one or more voltage-step-down circuits, and in each of the one or more voltage-step-down circuits the second transistor is connected between a second node of the inductor and the first supply voltage and the first transistor is connected to switchedly conduct current between the second node of the inductor and a second supply voltage.