Computer models of the field-effect transistor

The use of general network analysis programs to analyze complex electronic circuits requires that valid models be developed for the active devices in these circuits. A nonlinear model of the field-effect transistor is presented for use in large-signal applications. From this model several piecewise-linear models suitable for use with an Electronic Circuit Analysis Program (ECAP) are derived. The approximations usable in these models are evaluated, and models intended for use in pulse inverters are presented. Techniques for measuring the parameters in the models are described and results of the measurement of these parameters for a sample of field-effect transistors are given. Finally, the behavior of actual pulse inverter circuits is shown to compare favorably with ECAP-Computed circuit performance.