High Frequency Inductors for GaN Applications: Construction Analysis and Efficiency Comparison

Abstract:
With the increasing usage of high-frequency silicon power stages and the near-term, widespread adoption, of GaN/SiC it is necessary to take a detailed look at the existing power inductor technology to determine their compatibility with these new application conditions. At present there are multiple inductor technologies advertised as high-frequency solutions including various molded powder, composite core, magnetic resin and ferrite core solutions. This paper will review the construction of these various solutions, detail issues with calculating losses and present data and analysis of actual inductor loss measurements. In addition, inductor metrics are identified and used to compare inductor performance by way of component level testing and actual in-circuit power loss measurements. By comparing the resultant data, the most suitable solution for high-frequency applications is realized.