AN IMPROVED GATE CURRENT MODEL OF GAAS-FETS FOR NONLINEAR CIRCUIT SIMULATION

An improved gate current model of GaAs FET's is presented. A conventio nal gate current model has been determined only by the forward current and the reverse breakdown characteristics. Consequently, the model fa ils to fit measured results in the reverse bias range, under which pow er amplifiers operate. The proposed model improves this problem and sh ows a great enhancement in accuracy throughout the whole operation ran ge of FET's. The model consists of three diodes and a resistor, which are standard elements implemented in commercially available circuit si mulators, and thus it can easily be used for analyzing performances of various FET circuits.