A new mesfet nonlinear model

Abstract

In this paper, a new empirical model for the dc I-V characteristics of a GaAs MESFET transistor is presented. The conventional approach for modeling the dc I-V characteristics of a MESFET transistor adopts the hyperbolic-tangent dependent on Vds through the observation of the Ids versus Vvs curve. The derived model is capable of accurately modeling the device current-voltage behavior in different operation regions. The new model equations describe the device drain current as a polynomial of the effective gate-source voltage Veff, which is in turn a rational function of Vgs, and the parameters for the polynomial vary with Vds. Model parameter extraction is made for a 05 μm gate-length MESFET device. Measured and modeled results are compared, and good agreement is obtained. A comparison among the proposed model, Curtice's and Chalmer's model, and Parker's model are also made in this paper.