Creating Spice Models

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Here is an excellent page by Andy_C that documents his modeling of the MJL1302a/3281a power BJTs. The process is described in detail so you can do it yourself (although a bit advanced).

http://home.comcast.net/~andy_c_public/spice_models_1.htm

And if you're really in a bind, what's below is better than nothing. Don't make models with this and post them here. This is only a very rough approximation of characteristics from datasheet values, so the models will be questionable at best.

The BJT default in ISSPICE4 gives first order, Ebers-Moll, DC
parameters; but it does not provide parameters for Transient or
AC analysis. The following default can be used when minimal
data sheet specifications are available by using the PARAM
program to evaluate the equations in curly braces. This model
will create a good transistor model from virtually any data sheet.
The parameters you must specify are:

IMAX Maximum collector current
COB Collector-base capacitance
FT Gain bandwidth product in Hz
TS Storage time

The equation-based model is shown below:
.MODEL NBJT NPN (CJC={2.2*COB} TF={.16/FT} TR={1.7*TS}
+CJE={7*COB} RC={.5/IMAX} VAF=100 IKF={.7*IMAX}
+ IS={2E-15*MAX} )

This subcircuit-based macro model makes use of the default
model parameters so that it is not permissible to change default
values without reevaluating the parameters which are given
here.

References

This documents the Gummel-Poon BJT SPICE model:

http://www.electronics.oulu.fi/Opetus/ELJK/JUTUT/GP_DOCU.pdf

 

[sameerdhiman]

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