GaN Power Transistor Modeling for High-Speed Converter Circuit Design

A circuit simulator has been developed to design power losses of high-frequency power converters using GaN-based heterojunction field-effect transistors (GaN-HFETs). The simulator is based on a high-accuracy equivalent model of GaN-HFETs with peculiar device physics and high-speed loss calculation methods. The simulated power losses were consistent with measured results in dc-dc converters constructed by a GaN-HFET and a SiC Schottky diode with more than 93% accuracy. By utilizing the developed simulator, key requirements in heat-dissipation technologies, circuit parasitic inductances, and gate-drive technologies for next-generation converters are discussed.