A comprehensive electrothermal GaN HEMT model including nonlinear thermal effects

Abstract

A novel nonlinear high-power Gallium Nitride (GaN) High Electron-Mobility Transistor (HEMT) equivalent circuit model is described. Features of the model include a nonlinear thermal subnetwork extracted using straightforward measurement techniques, and a modified Angelov/Chalmers single function drain current equation. The model can very accurately predict the Pulsed IV (PIV) curves at different pulse widths and duty cycles from isothermal up to the safe-operating area (SOA) limit, with high voltage drain-source pulses. Large-signal one-tone-test results are presented and show good fidelity with measurements for the first three harmonics, as well as accurate prediction of bias point shifting with increasing input power.