New Double-Sided SMT Power Inductor

This paper presents the design and construction of new surface-mount technology (SMT) power inductors that allow for high-component packaging density and automated manufacturing of power converters. The inductors have double-sided SMT terminations, uniform profile (14 mm), reduced packaging (i.e., no coil former), and enhanced thermal properties. The inductor is implemented with drum and shield magnetic core parts. The thermal behavior of the inductors is improved by employing heat extractors and filling the air gaps by thermal glue. The electromagnetic and thermal designs of the inductors are given in detail. The method for designing novel x-dim inductors that results in the smallest drum and shield core parts for a given set of design parameters is presented. The designers of shielded drum inductors are provided by one-turn inductance values that include the fringing field effect in the form of fringing factor. New inductors have reduced size, enable effective heat removal, and are necessary building blocks in automated manufacturing of power converters.