Nonlinear resistor circuits using capacitively coupled multi-input MOSFETs

A family of nonlinear resistor circuits with A and V-type I-V characteristics is proposed by using capacitively coupled multi-input MOSFETs. Their I-V characteristics can be easily altered by external control voltages. Moreover, the proposed circuits are fully compatible with a standard CMOS semiconductor process because only enhancement-type MOSFETs are necessary. Furthermore, nonlinear capacitors can be used for the capacitively coupled multi-input MOSFETs in the proposed circuits, so that a simple digital CMOS process with nonlinear capacitors can be used to fabricate the proposed circuits. Simple equations for a numerical simulation of the circuits are derived. Moreover, results from numerical simulations and experiments with discrete elements are demonstrated.