Design and implementation of planar inductors for low voltage GaN-based power converters

The design and implementation of planar inductors in low voltage GaN-based applications is investigated, and design techniques conducive to inexpensive, simple implementations are utilized. The advantages and limitations of planar technology, as it relates to filter inductors, are presented. Design considerations such as core material, core geometry, number of turns, gap size, fringing fields, and winding construction are addressed, and several planar inductors are evaluated in a 12-to-1 V GaN-based synchronous buck converter. Experimental results are used to determine the feasibility and advantages of replacing commercially packaged components with planar inductors. The primary focus is to reduce inductor core loss, winding loss, size, and raise saturation current by employing well-designed planar inductors to modern, wide-bandgap power converters.