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FET parameters:



Parameter Definition
F1 Drain to source resistance $R_{ds}(\Omega)$
F2 Transconductance $G_{m}(1/\Omega)$
F3 Gate to source capacitance $C_{gs}(Farads)$
F4 Gate to drain capacitance $C_{gd}(Farads)$
F5 Drain to source capacitance $C_{ds}(Farads)$
F6 Drain bias current $I_{d}(Amps)$
F7 DC gate current $I_{g}(Amps)$
F8 Drain shot noise 1/f corner $(Hertz)$
F9 Gate shot noise 1/f corner $(Hertz)$



The noise sources are determined from the Gm, Id, and Ig parameters. See Appendix B for more information on FET noise sources.

Example:

* FET with Rds = 10K, Gm = .005, Cgs = 6pfd, Cgd = 2pfd,

* Cds = 1.5pfd, Id = 200uA, Ig = 50 pA,

* 1/f(drain) = 100Hz, 1/f(gate) = 1KHz.

.MODEL FET1 1.e4, .005, 6.e-12, 2.e-12, 1.5e-12, 2.e-4 \

     5.e-11, 100., 1.e3



Bob Smither 2008-11-19