Importing a SPICE model into Multisim from Fairchild

[arosenthal]

I am trying to import the following model into Multisim: http://www.fairchildsemi.com/ShoppingExperience/action/redirectModel?type=model&filename=FDV305N.mod

The SPICE model is for a N-Channel MOSFET.  It contains a 4th pin, for temperature.

I am not sure how to add this fourth PIN to Multisim, or how to remove the 4th pin from the SPICE model.

*FDV305N at Temp. Electrical Model
*-------------------------------------
.SUBCKT FDV305N 20 10 30 50
*20=DRAIN 10=GATE 30=SOURCE 50=VTEMP
.....
*TEMP SECTION
ED 101 0 VALUE {V(50,100)}
VAMB 100 0 25
.....
.ENDS FDV305N
*FDV305N (Rev.A) 7/1/02 **ST

[OStep]

The model includes temperature effects.

You would have to use the symbol editor within the Componen Wizard to add a 4th pin to an existing 3-pin Mosfet symbol. 

I created the component for you. The pin on the right side is this temperature pin. Apply a voltage (1V = 1degC) to simulate at the desired temperature. 

[arosenthal]

Thank you very much.  Could you explain exactly how you did that.  I was unable to figure it out myself.

[OStep]

There is an article that shows you how to use the Comonent Wizard: 

http://www.ni.com/white-paper/3173/en

If you do not require a layout footprint, then skip all those sections regarding footprint. Ensure to select "Simulation only" in step 1.

In the symbol step, click "Copy for db" to select a symbol already used by an existing component. Then click Edit to enter the symbol editor where you add any extra pins.

[arosenthal]

I did:

Tools -> Component Wizard

Component name: FDV305N

Simulation Only

Componet Type: Ananlog

Number of pins: 4

Add a 4th pin to an N-enhanced FET

4th pin name: Tj

Load model from file: FDV305N.mod (from fairchild.com)

I get this error: http://i.imgur.com/loA8RYY.png

Alan

[OStep]

well it tells you that ANSI and DIN symbols do not match with respect to pin count. You can ignore it if you're only using ANSI symbols in your schematics.