Hi to all,
I am using this spice description for a BSS159 Depletion mode Mosfet (I attached it as "Spice directive" in my LTSpice schematic):

** Infineon depletion mode mosfet, sot23
** Simplified model.
.SUBCKT BSS159N drain gate source

Lg gate g1 3n
Ld drain d1 1n
Ls source s1 3n
Rs s1 s2 0.074

Rg g1 g2 25
M1 d2 g2 s2 s2 DMOS L=1u W=1u
.MODEL DMOS NMOS ( KP= 0.241 VTO=-2.05 THETA=0 VMAX=1.5e5 ETA=0.005 LEVEL=3)
Rd d2 d1a 1.08 TC=9m
.MODEL MVDR NMOS (KP=1.5 VTO=-1.4 LAMBDA=0.1)
Mr d1 d2a d1a d1a MVDR W=1u L=1u
Rx d2a d1a 1m

Dbd s2 d2 Dbt
.MODEL Dbt D(BV=72 M=0.38 CJO=15.99p VJ=0.5V)
Dbody s2 21 DBODY
.MODEL DBODY D(IS=20p N=1.3 RS=1023u EG=1.12 TT=50n)
Rdiode d1 21 300m TC=0

.MODEL sw NMOS(VTO=0 KP=10 LEVEL=1)
Maux g2 c a a sw
Maux2 b d g2 g2 sw
Eaux c a d2 g2 1
Eaux2 d g2 d2 g2 -1
Cox b d2 55.9p
.MODEL DGD D(M=0.72 CJO=55.9p VJ=0.5)
Rpar b d2 1Meg
Dgd a d2 DGD
Rpar2 d2 a 10Meg
Cgs g2 s2 29.25p

.ENDS BSS159N

I'm using a generic MOSFET 4 terminal as symbol and I link the model as BSS159N.

But I have an error in simulation: "Can't find definition of bss159n".
Why?
I am not an expertize in Spice directives, it is possible that something is wrong in Spice description/directives?

 

Hi claudio,
Please post your LTS asc file, so that we can compare results.
E

 

Hi claudio,
Please post your LTS asc file, so that we can compare results.
E

Hi Ericgibbs,

Uhmm
What is the "LTS asc file"?

 

Hi.
It is the file of the circuit you are simulating in LTS.
E

 

Hi.
It is the file of the circuit you are simulating in LTS.
E

 

Here you have

 

Ohh, thanks!
May I ask what was wrong?

 

Hi claudio,
Check the changes in the Attributes menu, also 'nmos' not nmmos4
Hold down CTL ley and right click on the mos symbol
E

 

Hi claudio,
Check the changes in the Attributes menu, also 'nmos' not nmmos4
Hold down CTL ley and right click on the mos symbol
E

Thanks!!