Novel bias-dependent, small-signal model of the dual-gate MESFET
Abstract
A dual-gate MESFET from NEC (NE25000) has been measured and modeled. S-parameters and drain-to-source currents calculated from the model are in good agreement with measured data. The model consists of a cascade of two intrinsic single-gate, nonlinear FET-models embedded in a network representing the device parasitics. A step-by-step procedure has been used to determine the 47 parameters of the model. DC-measurements were used to find starting values for some of the parameters of the nonlinear models. The parasitic capacitances were determined from three-port S-parameters measured at V(sub DS) = 0 V, I(sub DS) = 0 A and V(sub G1S) = V(sub G2S) = - 4.0V. The parasitic inductances and resistances were determined from S-parameters measured at the same bias-point but with forward-biased gates, and from DC-measurements. The final model-optimization was done by simultaneously fitting the model to drain-to-source currents and three-port S-parameters measured at several different, active bias-points (V(sub DS) greater than 0).
- Publication:
-
IEEE Transactions on Microwave Theory Techniques
- Pub Date:
- February 1994
- DOI:
- 10.1109/22.275249
- Bibcode:
- 1994ITMTT..42..212S
- Keywords:
-
- Bias;
- Electric Current;
- Electric Networks;
- Field Effect Transistors;
- Gates (Circuits);
- Mathematical Models;
- Metals;
- Phase Shift Circuits;
- Semiconductor Devices;
- Capacitance;
- Embedding;
- Nonlinearity;
- Parameter Identification;
- Parasites;
- Electronics and Electrical Engineering