Design of microfabricated inductors

Possible configurations for microfabricated inductors are considered. Inductance can be set by adjusting permeability through control of anisotropy of a permalloy core, or via a patterned quasi-distributed gap. A design methodology based on a simple model is proposed. Analysis of secondary effects is also developed. A design example for a 5 MHz buck power converter application is presented. A power density of 12.8 W/cm/sup 2/ is possible for an efficiency of 94%.

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