A new planar microtransformer for use in macro-switching-converters

Abstract

A novel planar microtransformer for use in micro-switching converters of portable equipment is described. This microtransformer, consisting of planar coils and CoZrRe amorphous magnetic layers on a Si substrate, is fabricated by a dry process. It is approximately 0.3 mm thick and 4*4 mm/sup 2/. The coils have relatively high inductance of 50 nH/mm/sup 2/. This microtransformer is used in a primary-controlled forward converter, which operates well at 32 MHz.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>