Method and system for analysis and evaluation of semiconductor circuit

Abstract

A characteristic of a MOS transistor is represented using an equivalent model. The equivalent model shows a connection configuration made up of an electric current source which supplies an electric current and a resistor element which is connected in parallel with the electric current source. The electric current is given by the equation of i=G.sub.m .multidot.(V.sub.GS -V.sub.T) for V.sub.GS .gtoreq.V.sub.T where G.sub.m is a coefficient, V.sub.GS is a gate-to-source input voltage of said MOS transistor, and V.sub.T is a given threshold voltage. A plurality of operating zones of the MOS transistor are defined according to the drain, source, and gate terminal voltages of the MOS transistor and are assigned respective values of the coefficient G.sub.m and respective values of the resistor element's resistance. By such a representation, the circuit equation of a semiconductor circuit that is analyzed can be represented in the form of a linear time-invariant equation. Semiconductor circuit performance characteristics can be analyzed and evaluated at high accuracy and high speed.