Simple and Accurate Circuit Simulation Model for Gallium Nitride Power Transistors

Simple and accurate circuit simulation model for gallium nitride (GaN) power field-effect transistors (FETs) is presented and validated in high-frequency low-voltage synchronous buck (SB) dc-dc power converters. For comparison, simulation results are also presented for the power converter based on silicon power metal-oxide semiconductor (MOS)FETs with similar voltage and current ratings. An improvement in power conversion efficiency of more than 4% is reported with GaN power FETs compared to the best commercially available silicon power MOSFETs in a 19 V/1.2 V, 7 W SB dc-dc power converter with excellent load regulation. A temperature- and frequency-dependent power inductor model is also reported and is shown to be necessary in order to accurately model the converter performance.