Problem using Model Maker to generate an NMOS transistor

[MikeWebster]

I'm attempting to use Model Maker to create a custom NMOS model, but when I attempt to use the resulting model in Multisim I get a "unable to find model definition" error.

Here is the procedure that I am using:
Component Wizard
Name: Test2
Simulation Only
Single Section
3 pins
Copy 3 pin Enhancement mode symbol from DB
Default all bidirectional
Model Maker
MOSFET(4 pins: D,G,S,Sub)
I've tried making my own, but all defaults give me the same error as customizing the fields, so I just click OK here.
Model Name is filled in as MOSFET_MODEL_BSS83
After the comments section, the generated model looks like:
.MODEL Mosfet_MODEL_BSS83 NMOS
+ VTO=1.230e+000 PHI=6.500e-001 GAMMA=3.134e-001 LAMBDA=2.039e-001
+ KP = 1.461e-002 RD = 1.250e+001 RS = 1.250e+001
+ CBS=2.372e-012 CBD=1.977e-012 IS=2.500e-014
+ CGSO = 7.200e-009 CGDO = 6.000e-009 CGBO = 1.800e-009
+ MJ=4.600e-001 PB=8.000e-001  FC=5.00e-001

Connect S->3, D->1, G->2
Save to a user database and finish.
Add part to schematic
Hit simulate:
error in c:\docs\...\temp\02.CIR.cir(24):mU1 VCC Probe1_0V_SP_NODE 0 MOSFET_MODEL_BSS83__TEST__1
Error on line 24 in same as above
unable to find definition of model - default assumed

BJT's and diodes work fine when contructed using the same method.

I'm using Multisim 10.0.343 Power Pro Edition

Any help is appreciated.

[OStep]

Hello,

The Mosfet from the component wizard expects you to have 4 pins. If you only assigned 3 pins because your symbol only has 3 pins, this issue will arise. This is a limitation that will be addressed.

For now, if you dont want a 4th pin, the easiest solution is to wrap you mosfet in a subcircuit and run the component wizard where you manually paste the subcircuit into the model text box. Here's the template:

.subckt mymosfet_anyname d g s
M1 d g s s mosfet_model_name
.model mosfet_model_name nmos("parameter goes here"......)
.ends

where you would place your desired mosfet parameters in the brackets

Let me know how it goes...

[lacy]

That's a cool trick Max. Thanks for that information. If I ever need to create a Mosfet I will rememember this method. In fact, I am going to copy this information a place it in a safe place for future reference.

Very much appreciated, Max