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Vacuum Tube SPICE Models

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roger57

roger57

Member
Joined 2006
jazbo8 said:
Code: 
*
* Generic triode model: ECC40_AN
.ENDS
Click to expand...

I could not get this one to work, although everything seemed correct (in LTSpice) ?? Did it work on your simulation package jazbo8?
Thanks for posting it in any case!
RajkoM said:
Try this model Gary. If there is no good, I'm guilty:D
*$
Click to expand...

RajkoM, this model seemed to work OK. In my simulation, it performed substantially better than a 6SN7, with 20dB lower in the second harmonic. It's in a Anode loaded CCS DAC tube stage.

In the circuit, I have listed now for a few hours and it does sound good. I think that ECC40 has found a new home! For a tube that's 70 years old, it's still got the goods.

gr
 
jazbo8

jazbo8

Ex-Moderator
Joined 2011
Most of the time, the error comes from mis-matched pin order between the symbol and the model. For the Ayumi models, the pin order always goes from top to bottom: anode, control grid and cathode for the triodes, and anode, screen grid, control grid and cathode for the beam tetrodes/pentodes. Hoep this helps.
 
smoking-amp

smoking-amp

Member
Joined 2001
Has anyone done a Spice model for TV Sweep 6HJ5? Here is a datasheet curve for it (Vg2 = 160 V). One of only a few Sweep Tubes (6LQ6, & 6HJ5/6HD5) (also 300B) with a near square power law for grid 1. (& 1.3 power law for grid 2)
 

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Last edited:
jazbo8

jazbo8

Ex-Moderator
Joined 2011
smoking-amp said:
Has anyone done a Spice model for TV Sweep 6HJ5? Here is a datasheet curve for it (Vg2 = 160 V). One of only a few Sweep Tubes (6LQ6, & 6HJ5/6HD5) (also 300B) with a near square power law for grid 1. (& 1.3 power law for grid 2)
Click to expand...
I can use the triode curves found on this thread to make the SPICE models for the sweep tubes, but do you still have the information on the grid steps that were used in those shots?
 
jazbo8

jazbo8

Ex-Moderator
Joined 2011
6HJ5 Pentode & Triode-Connected Models

smoking-amp said:
Has anyone done a Spice model for TV Sweep 6HJ5?
Click to expand...
I tried making the models, the pentode below Eg=-15V is kinda rubbish when compared with the Raytheon datasheet, but give it a try to see if it meets your needs.

Pentode Model:
Code: 
*
* Generic pentode model: 6HJ5_AN
* Copyright 2003--2008 by Ayumi Nakabayashi, All rights reserved.
* Version 3.10, Generated on Mon Jan 19 16:01:51 2015
*               Plate
*               | Screen Grid
*               | |  Control Grid
*               | |  |  Cathode
*               | |  |  |
.SUBCKT 6HJ5_AN A G2 G1 K
BGG   GG   0 V=V(G1,K)+-1
BM1   M1   0 V=(0.11728428*(URAMP(V(G2,K))+1e-10))**-0.97657028
BM2   M2   0 V=(0.60567633*(URAMP(V(GG)+URAMP(V(G2,K))/3.3621186)))**2.4765703
BP    P    0 V=0.0055900813*(URAMP(V(GG)+URAMP(V(G2,K))/5.5510153))**1.5
BIK   IK   0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.0036761852*V(M1)*V(M2)
BIG   IG   0 V=0.0027950407*URAMP(V(G1,K))**1.5*(URAMP(V(G1,K))/(URAMP(V(A,K))+URAMP(V(G1,K)))*1.2+0.4)
BIK2  IK2  0 V=V(IK,IG)*(1-0.4*(EXP(-URAMP(V(A,K))/URAMP(V(G2,K))*15)-EXP(-15)))
BIG2T IG2T 0 V=V(IK2)*(0.952931274*(1-URAMP(V(A,K))/(URAMP(V(A,K))+10))**1.5+0.047068726)
BIK3  IK3  0 V=V(IK2)*(URAMP(V(A,K))+825)/(URAMP(V(G2,K))+825)
BIK4  IK4  0 V=V(IK3)-URAMP(V(IK3)-(0.0043717119*(URAMP(V(A,K))+URAMP(URAMP(V(G2,K))-URAMP(V(A,K))))**1.5))
BIP   IP   0 V=URAMP(V(IK4,IG2T)-URAMP(V(IK4,IG2T)-(0.0043717119*URAMP(V(A,K))**1.5)))
BIAK  A    K I=V(IP)+1e-10*V(A,K)
BIG2  G2   K I=URAMP(V(IK4,IP))
BIGK  G1   K I=V(IG)
* CAPS
CGA   G1  A  0.34p
CGK   G1  K  9.6p
C12   G1  G2 6.4p
CAK   A   K  7p
.ENDS

Triode-Connected:
Code: 
*
* Generic triode model: 6HJ5T_AN
* Copyright 2003--2008 by Ayumi Nakabayashi, All rights reserved.
* Version 3.10, Generated on Mon Jan 19 16:13:14 2015
*                Plate
*                | Grid
*                | | Cathode
*                | | |
.SUBCKT 6HJ5T_AN A G K
BGG   GG   0 V=V(G,K)+-0.99999998
BM1   M1   0 V=(0.11840663*(URAMP(V(A,K))+1e-10))**-1.0050033
BM2   M2   0 V=(0.59880161*(URAMP(V(GG)+URAMP(V(A,K))/3.3883101)+1e-10))**2.5050033
BP    P    0 V=0.0044372969*(URAMP(V(GG)+URAMP(V(A,K))/5.6584853)+1e-10)**1.5
BIK   IK   0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.0029670477*V(M1)*V(M2)
BIG   IG   0 V=0.0022186485*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)-(0.0034454575*URAMP(V(A,K))**1.5)))+1e-10*V(A,K)
BIGK  G    K I=V(IG)
* CAPS
CGA   G    A 0.34p
CGK   G    K 16p
CAK   A    K 7p
.ENDS
 
smoking-amp

smoking-amp

Member
Joined 2001
Thanks Jazbo8.

The grid 1 steps in those triode curves appear to be 2.7 V steps.

On re-checking the curve fit of the pentode Ip vs Vg1, I'm finding closer to 2.33 power law (exponent) now (cutoff Vg1 was more like -55V instead of -47V). For G2, Ip vs. Vg2 should be around a 1.33 exponent, which is typical for many tubes.

I have some actual tubes here, so I think I'll also take some V & I measurements to get the exponents for some real tube grids. So many published datasheets I have found have alternating Vg1 offset errors in the g1 plate curves, due to 60 Hz ripple in the curve tracer used (affecting Vg1 alternate curves, making them appear to bunch up in pairs, although the 6HJ5 datasheet seemed OK on that).

I'll give the models a try. Maybe I'll play around with the coeficients some too.
 
Last edited:
J

jmack

Member
Joined 2015
Jazbo8,

The latest User Manual latest I can find is dated 2009 (http://www.ni.com/pdf/manuals/374483d.pdf). Apparently NI thinks that either their (almost useless) "Help" function/file is now sufficient or things haven't changed enough to warrant updating the manual. However, neither the $40 "Student" version (which I bought for my son recently) nor the "$4000 PowerPro" (free download for evaluation) come with a User Manual.

Anyway, from page 414 of that Manual:

"Multisim incorporates SPICE3F5 and XSPICE at the core of its simulation
engine, with customized enhancements designed by National Instruments
specifically for optimizing simulation performance with digital and
mixed-mode simulation. Both SPICE3F5 and XSPICE are
industry-accepted, public-domain standards. SPICE3F5 is the most recent
edition of the SPICE (Simulation Program with Integrated Circuit
Emphasis) core designed by the University of California at Berkeley.
XSPICE is a set of unique enhancements made to SPICE, under contract to
the US Air Force, which include event-driven mixed mode simulation, and
an end-user extensible modelling subsystem. National Instruments has
further enhanced these cores with certain non-SPICE-standard Cadence®
PSpice® compatibility features to allow for using a wider range of
off-the-shelf SPICE models.
 
J

jmack

Member
Joined 2015
jackinnj,

In Multisim 13 the "Dc sweep" analysis works fast and well. That's why I'm interested in using the Ayumi models in my McIntosh MA230 simulation (to hopefully get more accurate distortion results.)

I'm also frustrated with Multisim and NI because their user feedback loop is apparently open. (I'm "gmack" on their user forum (Fix distortion analyses? - Discussion Forums). See their distortion analysis example starting on page 579 of their 2009 User Manual (and/or try it yourself).
 
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