A new rule for MESFET gate charge division based on the energy conservation principle

Abstract

SUMMARYThe energy conservation problem in the MESFET gate charge model is presented. The energy conservation requirement leads to symmetrical transcapacitances in contradiction to the commonly accepted approaches. The transcapacitance symmetry is completely independent of device symmetry. The resulting small-signal capacitances are reciprocal. Reciprocal capacitances are often considered charge nonconservative because they do not contain transcapacitances, but in this approach reciprocity is the result of transcapacitance symmetry and the charge conservation problem is avoided since the charge-based model includes the transcapacitances. A method for dividing the MESFET gate charge into gate-drain and gate-source portions based on the energy conservation rule is developed, and the method is applied to the well-known Statz gate charge as an example.