Z. MESFET Transistor

Symbol Names: MESFET

Syntax: Zxxx D G S model [area] [off] [IC=<Vds, Vgs>] [temp=<value>]

A MESFET transistor requires a model card to specify its characteristics. The model card keywords NMF and PMF specify the polarity of the transistor. The MESFET model is derived from the GaAs FET model described in H. Statz et al., GaAs FET Device and Circuit Simulation in SPICE, IEEE Transactions on Electron Devices, V34, Number 2, February, 1987 pp160-169.

Two ohmic resistances, Rd and Rs, are included. Charge storage is modeled by total gate charge as a function of gate-drain and gate-source voltages and is defined by the parameters Cgs, Cgd, and Pb.

NameDescriptionUnitsDefault
VtoPinch-off voltageV-2.
BetaTransconductance parameterA/V21e-4
BDoping tail extending parameter1/V0.3
AlphaSaturation voltage parameter1/V2.
LambdaChannel-length modulation1/V0.
RdDrain ohmic resistanceΩ0.
RsSource ohmic resistanceΩ0.
CgsZero-bias G-S junction capacitanceF0.
CgdZero-bias G-D junction capacitanceF0.
PbGate junction potentialV1.
KfFlicker noise coefficient-0.
AfFlicker noise exponent-1.
FcForward-bias depletion coefficient-0.5
IsJunction saturation currentA1e-14