Abstract: In this paper, we present an improved large-signal device model of GaAs/ GaN HEMTs, amenable for use in the commercial nonlinear simulators. The proposed model includes a new exponential function to independently control the transconductance (Gm) compression/ tail-off behaviors. And the main advantage of this model is to provide a simple and coherent description of the bias-dependent drain current (I-V) that is valid in all regions of operation. All the aspects of the model are validated for 0.25-μm gate-lengths GaAs and GaN HEMT processes. The simulation results of DC/ Pulsed I-V, RF large-signal power and intermodulation distortion (IMD) products show an excellent agreement with the measured data.

Key words: large-signal model,  parameter extraction,  HEMT