A 233-MHz 80%-87% efficient four-phase DC-DC converter utilizing air-core inductors on package

Peter Hazucha, Gerhard Schrom, Jaehong Hahn, Bradley A. Bloechel, Paul Hack, Gregory E. Dermer, Siva G. Narendra, Donald Gardner, Tanay Karnik, Vivek De, Shekhar Borkar. A 233-MHz 80%-87% efficient four-phase DC-DC converter utilizing air-core inductors on package. J. Solid-State Circuits, 40(4):838-845, 2005. [doi]