Patent ID: 7795761

Claim:
An apparatus comprising: a first switching element coupled between a first Direct Current (DC) voltage node and a first switching node; a second switching element coupled between a second DC voltage node and the first switching node; a third switching element coupled between a third DC voltage node and a second switching node; a fourth switching element coupled between a fourth DC voltage node and the second switching node; and a switch controller that controls at least two of the first, second, third, and fourth switching elements, wherein the apparatus is operable to receive at least one input voltage and to deliver at least one output voltage, wherein the apparatus is operable in a voltage step-up mode, wherein the apparatus can supply an output voltage that is higher than an input voltage, and a voltage step-down mode, wherein the apparatus can supply an output voltage that is lower than the input voltage, and wherein during at least one operating mode an output current flowing through the first switching node flows through no more than one of the first, second, third and fourth switches at a given time.