Integrating magnetics for on-chip power: Challenges and opportunities

Integration of efficient power converters requires a technology for efficient, high-power on-chip inductors. The state of the art is reviewed, and possible future developments are discussed for both air-core and magnetic-core inductors. Performance limits and scaling are analyzed. General design possibilities are outlined and different approaches are compared. Magnetic materials are reviewed, and nano-granular composite materials are highlighted as an attractive option.