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Micro-Cap Tubes Parameters question

I have Micro-Cap 9. It has a 6DJ8 tube in it. I'd like to change the parameters to a different tube, which isn't in it's database (6H30).

Those are the parameters for 6DJ8:

+PARAMS: LIP= 1.5 LIF= 10 RAF= 0.09 RAS= 0.2 CDO= 0
+ RAP= 0 ERP= 1.35
+ MU0= 33 MUR= 0.02 EMC= 0.0000795
+ GCO=-0.2 GCF= 0
+ CGA=1.40E-12 CGK=3.30E-12 CAK=1.80E-12

Out of those, I get what MU0, CGA, CGK and CAK are.
I have no clue what the other parameters mean.

Does anyone here know?
 
Thank you.
I wrote my initial post after looking at the tube manual.
As should be obvious from what I wrote above, I found in the tube manual the equivalent for MU0, CGA, CGK and CAK - so I know what they mean.
I didn't find in the tube manual any equivalent for the values of Micro-Cap for LIP, LIF, RAS, CDO, RAP, ERP, EMC, GCO and GCF - so I have no clue as of what they mean and how to alter them for a different tube.
 

kevinkr

Administrator
Paid Member
He wants to modify the parameters to those of other tube types. Best way to do this is to get the spice models and manually edit the params based on what is in the model you want to use.

Truthfully LTSpice IV does a much better job, is free and has no limitations on number of nodes or parts in a circuit being simulated. Lots of tube models all over the web for LTSpice as well.
 
Open tube.lib in MicroCap or a text editor and add this subckt to the library file.

.subckt 6H30 P G K
Gp P K VALUE=
+ {(0.3800825583m)*limit(V(P,K)*ln(1.0+(-0.02540430176)+exp((7.018331616)+
+ (7.018331616)*((15.85848193)+(-66.34009258m)*V(G,K))*V(G,K)/sqrt((27.2125877)**2+
+ (V(P,K)-(5.267363515))**2)))/(7.018331616),0,1e16)**(1.211856956)}

Cgk 6.3p
Cpk 2.4p
Cgp 6.0p

.ends 6H30

Save tube.lib. Now in MicroCap open the component editor. Windows ->Component Editor.
In the component editor on the right is the component tree.

Expand Tubes->Triode->then to whatever branch/group you would like to put the 6H30, like in my screenie below.

To add a group, click add group. To add your tube in a preexisting group, click add component.

Place 6H30 in 'name'. Use the drop down menus to select Shape->Triode, Definition->subckt.

Left click on each pin to set the node names/labels as in the screenie. Be sure that the dots are positioned at the end of each terminal.

Adjust the green XX YY positions to your liking. This is the text, part number/name (X1/6H30) that appears when you place the part on the schematic.

Close the component editor. When save changes dialog appears, choose yes.

That's it. ;)
 

Attachments

  • 6H30.png
    6H30.png
    18 KB · Views: 190
For these models, in the component editor assigning pin names...

Triode:
1 for plate
2 for grid
3 for cathode

Pentode:
1 for plate
2 for G2
3 for G1
4 for cathode

Code:
* 5687WA  -  IDH miniature medium-mu twin triode
* Gp  P K  VALUE={(m)*limit(()*V(G,K)+V(P,K),0.0,1.0e16)**1.5}
* From Tung-Sol 5687WA datasheet - traced on 15-09-01 by AF
.subckt 5687WA  P G K
    Cgp G P  4.0p
    Ci  G K  4.0p
    Co  P K  0.6p
* Modified Koren model (8 parameters): mean fit error 0.419449 mA
    Gp  P K  VALUE=
+ {(0.1055581311m)*limit(V(P,K)*ln(1.0+(-0.08954367978)+exp((5.455965239)+
+ (5.455965239)*((18.93648317)+(-42.34477259m)*V(G,K))*V(G,K)/sqrt((1.974234531e-06)**2+
+ (V(P,K)-(-7.478479923))**2)))/(5.455965239),0.0,1.0e16)**(1.31589849)}
.ends 5687WA
Code:
******************
.SUBCKT 7199T  1 2 3 ; P G C (Triode) ; TRIODE SECTION
* RCA 
* library format: LTSpice 01-Jun-2008
X1 1 2 3 TRIODE
+PARAMS: MU=32.71 EX=1.284 KG1=534.8 KP=52.95 KVB=300.0 VCT=0.00 RGI=2000 CCG=3.0p CGP=2.5p CCP=1.0p ; 
.ENDS 7199T
.SUBCKT TRIODE 1 2 3 ; A G C
+PARAMS: MU=102.50 EX=1.409 KG1=1598.8 KP=813.82 KVB=44.9 VCT=0.50 RGI=2000 CCG=2.3p CGP=2.4p CCP=0.9p ;
E1  7 0 VALUE={V(1,3)/KP*LN(1+EXP(KP*(1/MU+(V(2,3)+VCT)/SQRT(KVB+V(1,3)*V(1,3)))))}
RE1 7 0 1G
G1  1 3 VALUE={(PWR(V(7,0),EX)+PWRS(V(7,0),EX))/KG1}
RCP 1 3 1G    ; TO AVOID FLOATING NODES IN MU-FOLLOWER
C1  2 3 {CCG}  ; CATHODE-GRID
C2  2 1 {CGP}  ; GRID=PLATE
C3  1 3 {CCP}  ; CATHODE-PLATE
D3  5 3 DX     ; FOR GRID CURRENT
R1  2 5 {RGI}  ; FOR GRID CURRENT
.ENDS TRIODE
Code:
******************
.SUBCKT 7199P  1 2 3 4 ; A G2 G1 C (PENTODE) ; PENTODE SECTION
* RCA 
* library format: LTSpice 01-Jun-2008
XV1 1 2 3 4 PENTODE1
+ params: MU=97.92 EX=1.350 KG1=361.8 KG2=4500 KP=79.56 KVB=6.4 VCT=0.00 RGI=2000 CCG=5.7p CPG1=0.6p CCP=2.5p ; 
.ENDS 7199P
.SUBCKT PENTODE1 1 2 3 4 ; A G2 G1 C
+PARAMS: MU=47.04 EX=1.350 KG1=487.2 KG2=4500 KP=113.02 KVB=17.0 VCT=0.00 RGI=2000 CCG=5.7p CPG1=0.6p CCP=2.5p
RE1  7 0  1MEG    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE={V(2,4)/KP*LN(1+EXP((1/MU+V(3,4)/V(2,4))*KP))}    ; E1 BREAKS UP LONG EQUATION FOR G1.
G1   1 4  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG1*ATAN(V(1,4)/KVB)}
* G2   2 4  VALUE={(EXP(EX*(LN((V(2,4)/MU)+V(3,4)))))/KG2}
G2   2 4  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG2*(2.5708-ATAN(V(1,4)/KVB))}
* G2   2 4  VALUE={PWR(V(2,4)/MU+V(3,4),EX)/KG2}
RCP  1 4  1G      ; FOR CONVERGENCE    A  - C
C1   3 4  {CCG}   ; CATHODE-GRID 1    C  - G1
C2   1 3  {CPG1}  ; GRID 1-PLATE    G1 - A
C3   1 4  {CCP}   ; CATHODE-PLATE    A  - C
R1   3 5  {RGI}   ; FOR GRID CURRENT    G1 - 5
D3   5 4  DX      ; FOR GRID CURRENT    5  - C
.ENDS PENTODE1
In the 7199 models, the subckt calls the Triode 123 subckt and the Pentode1 subckt respectively. That's why there are two subckts in each model.

I don't have a model for a 7044...yet! I may trace one in CurveCaptor when I get a chance. :D
 
I made a mistake in the caps section for the 6H30 model. Corrected here:

Code:
.subckt 6H30  P G K
    Gp  P K  VALUE=
+ {(0.3800825583m)*limit(V(P,K)*ln(1.0+(-0.02540430176)+exp((7.018331616)+
+ (7.018331616)*((15.85848193)+(-66.34009258m)*V(G,K))*V(G,K)/sqrt((27.2125877)**2+
+ (V(P,K)-(5.267363515))**2)))/(7.018331616),0,1e16)**(1.211856956)}

Cgk G K 6.3p
Cpk P K 2.4p
Cgp G P 6.0p

.ends 6H30
 

jazbo8

Ex-Moderator
2011-01-05 8:34 am
In Transient
I have Micro-Cap 9. It has a 6DJ8 tube in it. I'd like to change the parameters to a different tube, which isn't in it's database (6H30).

Those are the parameters for 6DJ8:

+PARAMS: LIP= 1.5 LIF= 10 RAF= 0.09 RAS= 0.2 CDO= 0
+ RAP= 0 ERP= 1.35
+ MU0= 33 MUR= 0.02 EMC= 0.0000795
+ GCO=-0.2 GCF= 0
+ CGA=1.40E-12 CGK=3.30E-12 CAK=1.80E-12

Out of those, I get what MU0, CGA, CGK and CAK are.
I have no clue what the other parameters mean.

Does anyone here know?

I think the bundled models are from Duncan Munro, you can find the documentation here.

http://www.duncanamps.com/pdf/triodemodel30.pdf

Jaz
 
I think the bundled models are from Duncan Munro, you can find the documentation here.

http://www.duncanamps.com/pdf/triodemodel30.pdf

Jaz

Hi Jaz,
Thank you very much.
It is very helpful.
The linked document enables me to enter the spice parameters for any tube which I have its' data.

BTW, sometimes, some tubes datasheets don't include all parameters. However, those parameters can be derived, for a given working point, from the anode curves.