Low loss thin film magnetics for high frequency power supplies

Advances in wide bandgap semiconductor technologies have enabled increased switching frequencies, which is critical for reducing size of passive components in power supplies. These advances in power conversion technologies have highlighted the need for development of new class of magnetics components (inductors, transformers etc) with lower footprint and higher efficiency. Presently, the sizes of these magnetic components have been limited due to the use of low flux density ferrite as a core material. In this paper, we present the assembly and working of a nanocrystalline thin film inductor with low loss performance as a replacement for ferrite based inductors. The performance of the thin film inductor is characterized in a commercial 500 kHz evaluation board. The paper also shows the significant reduction in footprint with the thin film inductor using an oxide as insulation between magnetic layers.