ABSTRACT

A new physically based thermal noise model for MESFET's has been proposed, which is compatible with small signal equivalent circuit and large signal current-voltage characteristics. Specifically, the static feedback effect is taken into account to model noise characteristics correctly especially in low current regime. The gate and drain bias dependence of the gate noise voltage, the drain noise current, and the correlation coefficient between them has been investigated thoroughly, showing good agreement with experimental results from 0.5μm gate length MESFET. As a result, our formulation is successfully used to model bias dependence of the four noise parameters with reasonably good accuracy. Our model is simple and physical enough for device design and circuit simulation especially for MMIC application.