An Improved Model for GaAs MESFETs Suitable for a Wide Bias Range

In this letter, we present a new large signal model for GaAs metal-semiconductor field effect transistors, incorporating features for enhancing the bias range for which accuracy is maintained, for use in the simulation of microwave circuits. The model parameters for a specific case were extracted from a wide range of dc I-V and S-parameter data, and the simulated behavior was observed to match the measured data closely. The model includes the possibility of showing negative slopes of the I-V curves at high power without sacrificing accuracy in predicting radio frequency behavior, while remaining simple enough for use in simulation tools