Comparison of GaN and Si Devices in a 50 MHz Class Φ2 Converter

Abstract

GaN devices are promising for high frequency (HF) and very high frequency (VHF) applications. But high frequency loss mechanisms such as dynamic Rds,on and Coss loss can be significant and reduce their performance below what radio frequency (RF) silicon devices can achieve. We design and implement two 50 MHz class Φ2 converters to empirically compare the performance of GaN and Si devices at VHF. The experimental results show that the Si-based design with a resonant gate driver can achieve higher efficiency and better thermal performance compared to the GaN-based design with conventional gating circuitry.