A new planar microtransformer for use in micro-switching converters

A planar microtransformer for use in microswitching 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 about 0.3-mm thick, and 3*4 mm/sup 2/. Its coils provide a relatively high inductance of 33 nH/mm/sup 2/. This microtransformer is implemented in a forward converter, which operates well at 32 MHz. >