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lt spice mosfet model parameter

  • Thread starter Michael Robinson
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Michael Robinson

Jan 1, 1970
0
I'm using a model of the CD4007 that a friend sent me.
here it is:
..model CD4007 NMOS( Level=1 Gamma= 0 Xj=0 Tox=1200n Phi=.6 Rs=0 Kp=111u
Vto=2.0 Lambda=0.01 Rd=0 Cbd=2.0p Cbs=2.0p Pb=.8 Cgso=0.1p Cgdo=0.1p
Is=16.64p N=1)
LT Spice says it doesn't recognize Xj. So I looked it up. It is
metallurgical junction depth. I'm not sure why LTSpice doesn't recognize
the parameter, maybe my friend copied the model from PSpice, which uses
different names for the parameters or something. Anyway, I haven't had much
luck trying to find out what LTSpice calls the mystery parameter. Anybody
have words of wisdom, or maybe a better .model file for that mosfet? I am
looking for the n-mosfet in that chip. And by the way, I asked my buddy why
the model says Kp instead of Kn and he said LTSpice can calculate Kn from
Kp. Bottom line, I'm not sure this is such a great model to be using.
 
A

Andrew Holme

Jan 1, 1970
0
Michael Robinson said:
I'm using a model of the CD4007 that a friend sent me.
here it is:
.model CD4007 NMOS( Level=1 Gamma= 0 Xj=0 Tox=1200n Phi=.6 Rs=0 Kp=111u
Vto=2.0 Lambda=0.01 Rd=0 Cbd=2.0p Cbs=2.0p Pb=.8 Cgso=0.1p Cgdo=0.1p
Is=16.64p N=1)
LT Spice says it doesn't recognize Xj. So I looked it up. It is
metallurgical junction depth. I'm not sure why LTSpice doesn't recognize
the parameter, maybe my friend copied the model from PSpice, which uses
different names for the parameters or something. Anyway, I haven't had
much luck trying to find out what LTSpice calls the mystery parameter.
Anybody have words of wisdom, or maybe a better .model file for that
mosfet? I am looking for the n-mosfet in that chip. And by the way, I
asked my buddy why the model says Kp instead of Kn and he said LTSpice can
calculate Kn from Kp. Bottom line, I'm not sure this is such a great
model to be using.

I have the same model. I just deleted the Xj=0. It seems to give plausible
results.
 
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