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LTSpice simulation error using downloaded BF998 model from NXP

Hi, if anyone can help me solve this really annoying problem I'd be gratefu l. I have a downloaded BF998 model from NXP, I then got LTSpice to autogene rate a symbol and added it to my circuit, but when I try to simulate a real ly simple dc sweep I get "Can't find definition of model 'C'" errors.

This is the model from NXP

  • BF998 SPICE MODEL OCTOBER 1993 PHILIPS SEMICONDUCTORS
  • ENVELOPE SOT143 (R)
  • 1.: SOURCE; 2.: DRAIN; 3.: GATE 2; 4.: GATE 1; .SUBCKT BF998 1 2 3 4 L10 1 10 L=0.12N L20 2 20 L=0.12N L30 3 30 L=0.12N L40 4 40 L=0.12N L11 10 11 L=1.20N L21 20 21 L=1.20N L31 30 31 L=1.20N L41 40 41 L=1.20N C13 10 30 C=0.085P C14 10 40 C=0.085P C23 20 30 C=0.085P C24 20 40 C=0.005P D11 42 11 ZENER D12 42 41 ZENER D21 32 11 ZENER D22 32 31 ZENER RS 10 12 R=100 MOS1 61 41 11 12 GATE1 L=1.1E-6 W=1150E-6 MOS2 21 31 61 12 GATE2 L=2.0E-6 W=1150E-6 .MODEL ZENER D BV=10 CJO=1.2E-12 RS=10 .MODEL GATE1
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=140E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .MODEL GATE2
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=100E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .ENDS BF998

and this is my symbol that LTSpice made

Version 4 SymbolType BLOCK RECTANGLE Normal -32 -40 32 40 WINDOW 0 0 -40 Bottom 2 WINDOW 3 0 40 Top 2 SYMATTR Prefix X SYMATTR Value BF998 SYMATTR ModelFile C:\Users\Rob\Documents\LTSpice\LNA\spice_BF998.prm PIN 32 -16 LEFT 8 PINATTR PinName 1 PINATTR SpiceOrder 1 PIN 32 16 LEFT 8 PINATTR PinName 2 PINATTR SpiceOrder 2 PIN -32 -16 RIGHT 8 PINATTR PinName 3 PINATTR SpiceOrder 3 PIN -32 16 RIGHT 8 PINATTR PinName 4 PINATTR SpiceOrder 4

and finally my simple little circuit

Version 4 SHEET 1 880 680 WIRE 224 -64 -80 -64 WIRE -80 -32 -80 -64 WIRE -80 96 -80 48 WIRE 112 144 -208 144 WIRE 224 144 224 -64 WIRE 224 144 176 144 WIRE -208 176 -208 144 WIRE 112 176 -32 176 WIRE 224 176 176 176 WIRE -208 304 -208 256 WIRE -32 304 -32 176 WIRE -32 432 -32 384 WIRE 224 464 224 176 FLAG -208 304 0 FLAG -32 432 0 FLAG 224 464 0 FLAG -80 96 0 SYMBOL voltage -208 160 R0 WINDOW 39 24 124 Left 2 SYMATTR SpiceLine Rser=0 SYMATTR InstName VG2 SYMATTR Value 4 SYMBOL voltage -32 288 R0 SYMATTR InstName VG1 SYMBOL voltage -80 -48 R0 WINDOW 39 24 124 Left 2 SYMATTR SpiceLine Rser=0 SYMATTR InstName VDS SYMATTR Value 5 SYMBOL AutoGenerated\\BF998 144 160 R0 SYMATTR InstName U1 TEXT 8 344 Left 2 !.dc VG1 -1 1 0.1

Reply to
silverbackbowman
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What's that .prm file? The Vg1 should have a value. Why L=0.12n? That looks a bit redundant to me.

The .asy file looked ok, but should refer to bf998.sub.

-marcel

-- bf998.sub ---------------------------------------------------

  • BF998 SPICE MODEL OCTOBER 1993 PHILIPS SEMICONDUCTORS
  • ENVELOPE SOT143 (R)
  • 1.: SOURCE; 2.: DRAIN; 3.: GATE 2; 4.: GATE 1; .SUBCKT BF998 1 2 3 4 L10 1 10 0.12N L20 2 20 0.12N L30 3 30 0.12N L40 4 40 0.12N L11 10 11 1.20N L21 20 21 1.20N L31 30 31 1.20N L41 40 41 1.20N C13 10 30 0.085P C14 10 40 0.085P C23 20 30 0.085P C24 20 40 0.005P D11 42 11 ZENER D12 42 41 ZENER D21 32 11 ZENER D22 32 31 ZENER RS 10 12 100 MOS1 61 41 11 12 GATE1 L=1.1E-6 W=1150E-6 MOS2 21 31 61 12 GATE2 L=2.0E-6 W=1150E-6 .MODEL ZENER D BV=10 CJO=1.2E-12 RS=10 .MODEL GATE1
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=140E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .MODEL GATE2
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=100E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .ENDS BF998

-- test.net --------------

  • C:\spice\mhx\bf998\test.asc VG2 N002 0 4 Rser=0 VG1 N003 0 0.1 VDS N001 0 5 Rser=0 XU1 N001 0 N002 N003 BF998 .dc VG1 -1 1 0.1 .lib BF998.sub .backanno .end
Reply to
mhx

L=0.12n should simply be "0.12n". Vg1 is missing a dc value. What's that .prm file? The .asy file should link to the bf998.sub.

Works for me.

-marcel

-- bf998.sub ---------------------------------------------------

  • BF998 SPICE MODEL OCTOBER 1993 PHILIPS SEMICONDUCTORS
  • ENVELOPE SOT143 (R)
  • 1.: SOURCE; 2.: DRAIN; 3.: GATE 2; 4.: GATE 1; .SUBCKT BF998 1 2 3 4 L10 1 10 0.12N L20 2 20 0.12N L30 3 30 0.12N L40 4 40 0.12N L11 10 11 1.20N L21 20 21 1.20N L31 30 31 1.20N L41 40 41 1.20N C13 10 30 0.085P C14 10 40 0.085P C23 20 30 0.085P C24 20 40 0.005P D11 42 11 ZENER D12 42 41 ZENER D21 32 11 ZENER D22 32 31 ZENER RS 10 12 100 MOS1 61 41 11 12 GATE1 L=1.1E-6 W=1150E-6 MOS2 21 31 61 12 GATE2 L=2.0E-6 W=1150E-6 .MODEL ZENER D BV=10 CJO=1.2E-12 RS=10 .MODEL GATE1
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=140E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .MODEL GATE2
  • NMOS LEVEL=3 UO=600 VTO=-0.250 NFS=300E9 TOX=42E-9
  • NSUB=3E15 VMAX=100E3 RS=2.0 RD=2.0 XJ=200E-9 THETA=0.11
  • ETA=0.06 KAPPA=2 LD=0.1E-6
  • CGSO=0.3E-9 CGDO=0.3E-9 CBD=0.5E-12 CBS=0.5E-12 .ENDS BF998

-- test.net --------------

  • C:\spice\mhx\bf998\test.asc VG2 N002 0 4 Rser=0 VG1 N003 0 0.1 VDS N001 0 5 Rser=0 XU1 N001 0 N002 N003 BF998 .dc VG1 -1 1 0.1 .lib BF998.sub .backanno .end
Reply to
mhx

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Jones Joy Panicker

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