MESFET Models (NMF/PMF)

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MESFET Models (NMF/PMF)

The MESFET model is derived from the GaAs FET model of Statz et al. as described in [11]. The dc characteristics are defined by the parameters VTO, B, and BETA, which determine the variation of drain current with gate voltage, ALPHA, which determines saturation voltage, and LAMBDA, which determines the output conductance. The formula are given by:

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.

name

parameter

units

default

example

area

VTO

pinch-off voltage

V

-2.0

-2.0

 

BETA

transconductance parameter

A/V2

1.0e-4

1.0e-3

*

B

doping tail extending parameter

1/V

0.3

0.3

*

ALPHA

saturation voltage parameter

1/V

2

2

*

LAMBDA

channel-length modulation parameter

1/V

0

1.0e-4

 

RD

drain ohmic resistance

Ohms

0

100

*

RS

source ohmic resistance

Ohms

0

100

*

CGS

zero-bias G-S junction capacitance

F

0

5pF

*

CGD

zero-bias G-D junction capacitance

F

0

1pF

*

PB

gate junction potential

V

1

0.6

 

KF

flicker noise coefficient

-

0

 

 

AF

flicker noise exponent

-

1

 

 

FC

coefficient for forward-bias depletion capacitance formula

-

0.5

 

 

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