New double sided SMT power inductor

Abstract

The paper presents the design and construction of new SMT power inductors that allow for high components packaging density and automated manufacturing of power converters. The inductors are double sided SMDs with a uniform profile (14mm), reduced packaging (i.e. no coil former) and enhanced thermal properties. The inductor is implemented with drum and shield magnetic core parts. The thermal behaviour of the inductors is improved by employing heat extractors and filling the air gaps by thermal glue. Several inductor samples for different power levels and applications have been manufactured. The electromagnetic and thermal designs of the inductors are given in details. Because of larger air gaps the inductance value is calculated with the aid of FEM to include fringing field effects. The simulated inductance value match measured inductance value within ±3%. New inductors have reduced size, enable effective heat removal and are necessary building blocks in automated manufacturing of power converters.