CA3140 model. Again!

Lostgallifreyan · 2012-01-21T18:41:55+00:00

In what context did this model ever work in LTspice used as supplied? I can't find one. I have no trouble with any other amp model I need to use, but in all the realworld CA3140 situations I have emulated in LTspice, THIS model fails, with an interesting variety of errors.Now I am NOT interested in what spurious ways I might be gettign it WRONG, I'll work that out in my own time withotu bothering anyone at all. Right now I want to know if it EVER worled RIGHT. In complete context please. If I can see proof that it works, I'll start to figure out why I can never use it.(It's interesting to me that on the web at larghe, though this model has been accepted gratefully many times, no-one has ever actually said whether they managed to USE it or not.)*$ model description: "awbca3140"*a Device model created by analog_uprev for ca3140 on Thu Mar 118:48:14 IST 2001..subckt awbca3140 1 36 15 20 12*START OF DECK* +IN -IN OUT +VSS -VSS*NODE: 1 36 15 20 12*------INPUT STAGE-------VOSBAL 7 29 3.00000000E-03EU1 8 1 20 12 0.0001EU2 8 7 5 12 -1RB1 12 10 1 TC= 1.991040E-03 (-1.244400E-04)IB4 10 12 1.000000E-06RB3 12 5 8743.17 TC= 1.60000000E-03 (0.00000000E+00)IB3 12 5 5.718750E-07G1 12 1 10 12 1.025000E-05G2 12 36 10 12 9.750000E-06RDM 36 29 1.500000E+12RCM 31 13 1.500000E+12CDM 36 29 4.000000E-12G5 31 13 36 31 6.66667E-13G6 31 13 1 31 6.66667E-13*------INTERMEDIATE STAGE-------GDM 31 16 29 36 1GCM 31 16 13 31 -1.58113883E-05R1 31 16 3.16358380E+02C1 31 16 6.45457E-11VCP 23 31 100VCM 24 31 -100DD1 16 23 MD2..MODEL MD2 D XTI=1.000000P* SPECTRE: + IMAX=1000DD2 24 16 MD2G3 31 6 16 31 -1.07249255E-06R2 31 6 100000C2 11 6 1.2E-11RP1 31 20 3750RP2 31 12 3750*------OUTPUT STAGE-------G4 31 11 6 31 -5.10867719E+01ROUT 31 11 60DD3 11 9 MD3..MODEL MD3 D IS=10.0F XTI=1.0P N= 3.612647E-01* SPECTRE: + IMAX=1000DD4 9 11 MD4..MODEL MD4 D IS=10.0F XTI=1.0P N= 8.028126E-01* SPECTRE: + IMAX=1000EU6 9 31 2 31 1RO1 11 26 20FF1 31 28 VFF1 1VFF1 26 2 0.0FF2 31 20 VFF2 -1VFF2 33 31 0.0FF3 12 31 VFF3 -1VFF3...

Jan 21, 2012 81 Replies

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Gawd! You're so dense you've become a Slowman look-alike.

In... Message-ID:

I said, "I modeled the output with only a current limit... no swing bounds except for the feedback." [YOUR feedback loop]

In... Message-ID:

I said, "The model I'm pondering in my head takes my present basic model..."

[My "present basic model" is not what I tried to use to fit the CAcrap (because of its weirdness), look on my website or Google to see it.]

"with GDC, GBW, slew-rate, Rout, phase-margin, and positive and negative swing limit specifiable... but modified as follows:

Rout => Rout-sourcing, Rout-sinking (separate values) Current limit sourcing and sinking (separate values) Power supply pins will reflect load _and_ quiescent currents Output swing limits specifiable relative to rail potentials

It may even show recovery time from slamming into rails... not quite sure yet, but I think so :-)"

So do what you want. If you think I give a rat's ass what you do or think, you're sadly mistaken. ...Jim Thompson

Jim Thompson wrote in news: snipped-for-privacy@4ax.com:

Well, I'm going to leave it there. I haven't time or inclination to argue. I don't understand all that you have said, but I have tried to help my getting measurements, and I do understand that a model that forever reason generates impossible voltages is not usable. I asked you several times if you could help with details I could use to explore the original schematic, and all you did was give me a model that outputs more energy below its negative rail than the input could ever feed it, and a claim that the datasheet is lying.

Now, I have no way to judge that last claim, but I do think this effort is on a hiding to nothing, so I'm quite happy to abandon it now. Thanks for the effort you put into it. It's good to see anyone have a go, regardless of outcome.

CA3140 model. Again!

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