Nonquasi-Static Large-Signal Model of GaN FETs through an Equivalent Voltage Approach

A new empirical nonlinear model of GaN-based electron devices is presented in the paper. The model takes into account low-frequency dispersion due to self-heating and charge-trapping phenomena and provides accurate predictions at frequencies where nonquasi-static effects are important. The model is based on the application of a recently proposed equivalent-voltage approach and is identified by using pulsed measurements of drain current characteristics and pulsed S-parameter sets. Full experimental validation on a GaN on SiC PHEMT is provided at both small- and large-signal operating conditions.