BJT parameters:

Parameter	Definition
F1	Base spreading resistance $R_{bb'}(\Omega)$
F2	Active base to emitter resistance $R_{b'e}(\Omega)$
F3	Collector to active base resistance $R_{cb'}(\Omega)$
F4	Collector to emitter resistance $R_{ce}(\Omega)$
F5	Transconductance $G_{m}(1/\Omega)$
F6	Active base to emitter capacitance $C_{b'e}(Farads)$
F7	Collector to active base capacitance $C_{cb'}(Farads)$
F8	Collector to emitter capacitance $C_{ce}(Farads)$
F9	Collector bias current $I_{c}(Amps)$
F10	Base bias current $I_{b}(Amps)$
F11	Collector shot noise 1/f corner $(Hertz)$
F12	Base shot noise 1/f corner $(Hertz)$

The noise sources are determined from the Rb'e, Ic, and Ib parameters. See Appendix B for more information on BJT noise sources.

Example:

*2N2222 with Rbb' = 60, Rb'e = 2.58K, Rcb' = 5.16M

* Rce = 333K, Gm = .0388, Cb'e = 30pfd

* Ccb' = 2.5pfd, Cce = 8pfd, Ic, Ib defaulted

* 1/f(collector) = 200Hz, 1/f(base) = 100Hz.

.MODEL 2N2222 60., 2.58e3, 5.16e6 \

     3.33e5, .0388, 30.e-12 \

     2.5e-12, 8.e-12, 0., 0. \

     200., 100.

The parameters Gm, Rb'e, Ic and Ib are used as follows:

If Gm and Rb'e are specified and Ic and Ib are set to 0.0 then Ic and Ib are estimated by CCICAP as:

Ic = Vt * Gm Ib = Vt / Rb'e

where Vt = kT/q. The estimated values are used in any subsequent noise calculations.

If Ic and Ib are specified as positive and Gm and Rb'e are set to 0.0 then Gm and Rb'e are estimated by CCICAP as:

Gm = Ic / Vt Rb'e = Ic / (Ib * Gm).

If Ic and Ib are specified as positive and Gm and Rb'e are specified then Gm and Rb'e are not changed and the specified Ic and Ib are used in the noise calculation for the device.

If Ic and Ib are specified as negative, their values are set to zero and there will be no noise contribution from them. Gm and Rb'e are not changed and must be specified.