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Vacuum Tube SPICE Models

6KT8

I've created a model for the triode of the 6KT8.

Code:
*
* Generic triode model: 6KT8-Triode
* Copyright 2003--2008 by Ayumi Nakabayashi, All rights reserved.
* Version 3.10, Generated on Tue Jul 29 15:14:00 2014
*                   Plate
*                   | Grid
*                   | | Cathode
*                   | | |
.SUBCKT 6KT8-Triode A G K
BGG   GG   0 V=V(G,K)+0.21127936
BM1   M1   0 V=(0.0039561161*(URAMP(V(A,K))+1e-10))^-0.75363001
BM2   M2   0 V=(0.66559284*(URAMP(V(GG)+URAMP(V(A,K))/84.529157)+1e-10))^2.25363
BP    P    0 V=0.0058042243*(URAMP(V(GG)+URAMP(V(A,K))/126.9983)+1e-10)^1.5
BIK   IK   0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.0034550891*V(M1)*V(M2)
BIG   IG   0 V=0.0029021122*URAMP(V(G,K))^1.5*(URAMP(V(G,K))/(URAMP(V(A,K))+URAMP(V(G,K)))*1.2+0.4)
BIAK  A    K I=URAMP(V(IK,IG)-URAMP(V(IK,IG)-(0.0029708017*URAMP(V(A,K))^1.5)))+1e-10*V(A,K)
BIGK  G    K I=V(IG)
* CAPS
CGA   G    A 3p
CGK   G    K 3.2p
CAK   A    K 1.6p
.ENDS
Could anyone create a model for the pentode? I can't get the knee sharp enough with Ayumi's method.
 

Attachments

  • 6KT8.pdf
    475.8 KB · Views: 72
  • Overlay.png
    Overlay.png
    325.5 KB · Views: 488
  • 6KT8T.csv.txt
    1.2 KB · Views: 86
I believe I have a good model for the pentode 6KT8

Code:
**** 6KT8P ******************************************
* Created on 07/31/2014 13:59 using paint_kit.jar 2.6 
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: 6KT8P.png
* Data source link: 
*----------------------------------------------------------------------------------
.SUBCKT PENT_6KT8P 1 2 3 4 ; P G K G2
+ PARAMS: CCG=7.5P  CGP=0.046P CCP=2.2P RGI=2000
+ MU=363.3 KG1=144.6 KP=83.7 KVB=7.13 EX=1.77 KG2=0.22 
* Vp_MAX=500 Ip_MAX=35 Vg_step=0.5 Vg_start=0 Vg_count=8
* Rp=1600 Vg_ac=23.5 P_max=2.5 Vg_qui=-23.4 Vp_qui=240 UL=0.464 EG2=125
* X_MIN=45 Y_MIN=40 X_SIZE=531 Y_SIZE=370 FSZ_X=1044 FSZ_Y=696 XYGrid=false
* showLoadLine=n showIp=y isDHT=n isPP=n isAsymPP=n isUL=n showDissipLimit=y 
* showIg1=n gridLevel2=n isInputSnapped=n  
* XYProjections=n harmonicPlot=y harmonics=y
*----------------------------------------------------------------------------------
RE1  7 0  1MEG    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(4,3)/KP*LOG(1+EXP((1/MU+V(2,3)/V(4,3))*KP))}
G1   1 3  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG1*ATAN(V(1,3)/KVB)}
G2   4 3  VALUE={(EXP(EX*(LOG((V(4,3)/MU)+V(2,3)))))/KG2}
RCP  1 3  1G      ; FOR CONVERGENCE
C1   2 3  {CCG}    ; CATHODE-GRID 1
C2   1 2  {CGP}  ; GRID 1-PLATE
C3   1 3  {CCP}   ; CATHODE-PLATE
R1   2 5  {RGI}   ; FOR GRID CURRENT
D3   5 3  DX      ; FOR GRID CURRENT
.MODEL DX D(IS=1N RS=1 CJO=10PF TT=1N)
.ENDS
*$
This first two bias lines aren't exactly on, but I think it looks decent enough (though I'm still pretty new at this so I could be totally wrong.) :p
 

Attachments

  • 6KT8.pdf
    475.8 KB · Views: 65
  • 6KTP_Paint_Kip.png
    6KTP_Paint_Kip.png
    188.9 KB · Views: 479
  • 6KT8P.inc.txt
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I believe I have a good model for the pentode 6KT8

This first two bias lines aren't exactly on, but I think it looks decent enough (though I'm still pretty new at this so I could be totally wrong.) :p

Turns out the model I posted yesterday was actually pretty crappy lol. It didn't simulate in LTSpice at all and I had to tweak the subckt because the nodes didn't match up with the pentode/tetrode symbol I have. The model below is the tweaked one from the LTSpice picture, but I've attached the file that was generated by Paint_Kip if anyone wants to tweak it further.

Code:
**** 6KT8P ******************************************
* Created on 08/01/2014 09:21 using paint_kit.jar 2.6
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: 6KT8P.png
* Data source link:
*----------------------------------------------------------------------------------
.SUBCKT PENT_6KT8P 1 2 3 4 ; P G K G2
+ PARAMS: CCG=7.5P  CGP=0.046P CCP=2.2P RGI=2000
+ MU=10000 KG1=86.8 KP=96.3 KVB=5.63 EX=1.5 KG2=0.176
* Vp_MAX=500 Ip_MAX=35 Vg_step=0.5 Vg_start=0 Vg_count=8
* Rp=7680 Vg_ac=5.88 P_max=2.5 Vg_qui=-0.292 Vp_qui=204 UL=4.51 EG2=125
* X_MIN=45 Y_MIN=39 X_SIZE=531 Y_SIZE=370 FSZ_X=1254 FSZ_Y=696 XYGrid=false
* showLoadLine=n showIp=n isDHT=n isPP=n isAsymPP=n isUL=n showDissipLimit=n
* showIg1=n gridLevel2=n isInputSnapped=n
* XYProjections=n harmonicPlot=y harmonics=y
*----------------------------------------------------------------------------------
RE1  7 0  1MEG    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(2,4)/KP*LOG(1+EXP((1/MU+V(3,4)/V(2,4))*KP))}
G1   1 4  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG1*ATAN(V(1,4)/KVB)}
G2   2 4  VALUE={(EXP(EX*(LOG((V(2,4)/MU)+V(3,4)))))/KG2}
RCP  1 4  1G      ; FOR CONVERGENCE
C1   3 4  {CCG}    ; CATHODE-GRID 1
C2   1 3  {CGP}  ; GRID 1-PLATE
C3   1 4  {CCP}   ; CATHODE-PLATE
R1   3 5  {RGI}   ; FOR GRID CURRENT
D3   5 4  DX      ; FOR GRID CURRENT
.MODEL DX D(IS=1N RS=1 CJO=10PF TT=1N)
.ENDS
*$

Besides the screen current this new model seems to be a keeper. :D
 

Attachments

  • Spice.png
    Spice.png
    37.3 KB · Views: 459
  • Kip.png
    Kip.png
    191.7 KB · Views: 470
  • 6KT8P.inc.txt
    1.4 KB · Views: 62
  • 6KT8P_For_Paint_Kip.inc .txt
    1.4 KB · Views: 63
  • 6KT8.pdf
    475.8 KB · Views: 57
6ER5 Triode

Code:
*
* Generic triode model: 6ER5
* Copyright 2003--2008 by Ayumi Nakabayashi, All rights reserved.
* Version 3.10, Generated on Fri Aug  1 15:09:59 2014
*            Plate
*            | Grid
*            | | Cathode
*            | | |
.SUBCKT 6ER5 A G K
BGG   GG   0 V=V(G,K)+0.20684562
BM1   M1   0 V=(0.017253359*(URAMP(V(A,K))+1e-10))^-2.6665979
BM2   M2   0 V=(0.36000594*(URAMP(V(GG)+URAMP(V(A,K))/37.093881)+1e-10))^4.1665979
BP    P    0 V=0.0091669979*(URAMP(V(GG)+URAMP(V(A,K))/103.03686)+1e-10)^1.5
BIK   IK   0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.042512831*V(M1)*V(M2)
BIG   IG   0 V=0.004583499*URAMP(V(G,K))^1.5*(URAMP(V(G,K))/(URAMP(V(A,K))+URAMP(V(G,K)))*1.2+0.4)
BIAK  A    K I=URAMP(V(IK,IG)-URAMP(V(IK,IG)-(0.0047172745*URAMP(V(A,K))^1.5)))+1e-10*V(A,K)
BIGK  G    K I=V(IG)
* CAPS
CGA   G    A 0.38p
CGK   G    K 4.4p
CAK   A    K 3p
.ENDS
 

Attachments

  • 6ER5.inc.txt
    853 bytes · Views: 72
  • Overlay.png
    Overlay.png
    596.2 KB · Views: 446
  • 6ER5.pdf
    111 KB · Views: 61
  • 6ER5.csv.txt
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6BS8

Code:
*
* Generic triode model: 6BS8
* Copyright 2003--2008 by Ayumi Nakabayashi, All rights reserved.
* Version 3.10, Generated on Fri Aug  1 16:29:30 2014
*            Plate
*            | Grid
*            | | Cathode
*            | | |
.SUBCKT 6BS8 A G K
BGG   GG   0 V=V(G,K)+0.1396991
BM1   M1   0 V=(0.010461639*(URAMP(V(A,K))+1e-10))^-0.68684648
BM2   M2   0 V=(0.6859192*(URAMP(V(GG)+URAMP(V(A,K))/30.02214)+1e-10))^2.1868465
BP    P    0 V=0.0046594327*(URAMP(V(GG)+URAMP(V(A,K))/43.769207)+1e-10)^1.5
BIK   IK   0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.0027247899*V(M1)*V(M2)
BIG   IG   0 V=0.0023297163*URAMP(V(G,K))^1.5*(URAMP(V(G,K))/(URAMP(V(A,K))+URAMP(V(G,K)))*1.2+0.4)
BIAK  A    K I=URAMP(V(IK,IG)-URAMP(V(IK,IG)-(0.0024903068*URAMP(V(A,K))^1.5)))+1e-10*V(A,K)
BIGK  G    K I=V(IG)
* CAPS
CGA   G    A 1.15p
CGK   G    K 2.6p
CAK   A    K 1.3p
.ENDS
 

Attachments

  • 6BS8.csv.txt
    689 bytes · Views: 62
  • 6BS8.pdf
    506.9 KB · Views: 76
  • Overlay.png
    Overlay.png
    320.6 KB · Views: 126
  • 6BS8.inc.txt
    855 bytes · Views: 61
FYI....

It would seem that Mouser electronics has a new spice simulator coming out. It does simulations, has 100K parts inventory, pcb layout, and integrates the BOM into your mouser cart. I signed up for the notification of release and it will be really interesting to see if our tube models will work with this.
 
FYI....

It would seem that Mouser electronics has a new spice simulator coming out. It does simulations, has 100K parts inventory, pcb layout, and integrates the BOM into your mouser cart. I signed up for the notification of release and it will be really interesting to see if our tube models will work with this.

Interesting. Do you have a link on the Mouser site?
 
I installed tried to use the Ayumi models with LTSpice.
I replaced in all the ".mod" files each "^" with "**".

LTSpice gives the following error message for 2A3 and others:

WARNING: Can't resolve .param gg=(v(g,k)+-0.47258991)

Looking in the "2A3.mod" file, I find the offending line:

.param gg=(v(g,k)+-0.47258991)

It seems that LTSpice doesn't like it: maybe a parameter cannot depend on a voltage like v(g,k) ?

Does anyone have a fix for this ?
 
Member
Joined 2004
Paid Member
Is this the original Ayumi model?

"*
* Generic triode model: 2A3
* Copyright 2003--2006 by Ayumi Nakabayashi, All rights reserved.
* Version 3.01, Generated on Wed Mar 22 17:19:23 2006
.SUBCKT 2A3 A G K
BGG GG 0 V=V(G,K)+-0.47258991
BEP EP 0 V=URAMP(V(A,K))+1e-10
BEG EG 0 V=URAMP(V(G,K))+1e-10
BM1 M1 0 V=(0.056835059*(URAMP(V(EP)-1e-10)+1e-10))^-0.4044593
BM2 M2 0 V=(0.78762513*(URAMP(V(GG)+V(EP)/3.7366878)+1e-10))^1.9044593
BP P 0 V=0.0012053852*(URAMP(V(GG)+V(EP)/4.7442465)+1e-10)^1.5
BIK IK 0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.000709416*V(M1)*V(M2)
BIG IG 0 V=0.00060269261*V(EG)^1.5*(V(EG)/(V(EP)+V(EG))*1.2+0.4)
BIAK A K I=URAMP(V(IK,IG)-URAMP(V(IK,IG)-(0.0010032299*V(EP)^1.5)))+1e-10*V(A,K)
BIGK G K I=V(IG)
* CAPS
CGA G A 16.5p
CGK G K 7.5p
CAK A K 5.5p
.ENDS"

Change all "^" to"**".

"*
* Generic triode model: 2A3
* Copyright 2003--2006 by Ayumi Nakabayashi, All rights reserved.
* Version 3.01, Generated on Wed Mar 22 17:19:23 2006
.SUBCKT 2A3 A G K
BGG GG 0 V=V(G,K)+-0.47258991
BEP EP 0 V=URAMP(V(A,K))+1e-10
BEG EG 0 V=URAMP(V(G,K))+1e-10
BM1 M1 0 V=(0.056835059*(URAMP(V(EP)-1e-10)+1e-10))**-0.4044593
BM2 M2 0 V=(0.78762513*(URAMP(V(GG)+V(EP)/3.7366878)+1e-10))**1.9044593
BP P 0 V=0.0012053852*(URAMP(V(GG)+V(EP)/4.7442465)+1e-10)**1.5
BIK IK 0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.000709416*V(M1)*V(M2)
BIG IG 0 V=0.00060269261*V(EG)**1.5*(V(EG)/(V(EP)+V(EG))*1.2+0.4)
BIAK A K I=URAMP(V(IK,IG)-URAMP(V(IK,IG)-(0.0010032299*V(EP)**1.5)))+1e-10*V(A,K)
BIGK G K I=V(IG)
* CAPS
CGA G A 16.5p
CGK G K 7.5p
CAK A K 5.5p
.ENDS"
 
I installed tried to use the Ayumi models with LTSpice.
I replaced in all the ".mod" files each "^" with "**".

LTSpice gives the following error message for 2A3 and others:

WARNING: Can't resolve .param gg=(v(g,k)+-0.47258991)

Looking in the "2A3.mod" file, I find the offending line:

.param gg=(v(g,k)+-0.47258991)

It seems that LTSpice doesn't like it: maybe a parameter cannot depend on a voltage like v(g,k) ?

Does anyone have a fix for this ?
Yes... use the "xxx.inc" files in LTspice. ;)