Problems with SPICE models from vendors

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail opamps,
and found that almost all i tried gave me the same kind of cryptic square
root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only one
tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to work
(and more or less correctly), but i need to get a working AD8605 model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605 model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

On Fri, 25 Mar 2005 09:26:21 GMT, Robert Baer
robertbaer_at_earthlink.net> wrote:

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

----- Original Message -----
From: "Jim Thompson" <thegreatone_at_example.com
Newsgroups: sci.electronics.cad
Sent: Friday, March 25, 2005 3:37 PM
Subject: Re: Problems with SPICE models from vendors


On Fri, 25 Mar 2005 09:26:21 GMT, Robert Baer
robertbaer_at_earthlink.net> wrote:

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

Hello Jim,
this wasn't necessary. This AD8605 model runs without any
convergence problem in LTspice. So the model doesn't have any error.
Yuu should withdraw your email to AD and apologize to the manager
you have contacted for any inconvenience. :)

Best Regards,
Helmut

On Fri, 25 Mar 2005 16:00:04 +0100, "Helmut Sennewald"
helmutsennewald_at_t-online.de> wrote:

----- Original Message -----
From: "Jim Thompson" <thegreatone_at_example.com
Newsgroups: sci.electronics.cad
Sent: Friday, March 25, 2005 3:37 PM
Subject: Re: Problems with SPICE models from vendors


On Fri, 25 Mar 2005 09:26:21 GMT, Robert Baer
robertbaer_at_earthlink.net> wrote:

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

Hello Jim,
this wasn't necessary. This AD8605 model runs without any
convergence problem in LTspice. So the model doesn't have any error.
Yuu should withdraw your email to AD and apologize to the manager
you have contacted for any inconvenience. :)

Best Regards,
Helmut


I simply passed on the posting to the ADI manager.

As previously noted, I, personally, have experienced issues with ADI
models.

...Jim Thompson

"Robert Baer" <robertbaer_at_earthlink.net> schrieb im Newsbeitrag
news:1PQ0e.3481$gI5.1145_at_newsread1.news.pas.earthlink.net...
The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps,
and found that almost all i tried gave me the same kind of cryptic
square
root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the
only one
tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known
to work
(and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the latter
of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just

yesterday - implying the problem is not fixed.

Can anyone help?

Hello Robert,
I don't believe that you really can judge the quality of these
models as a beginner with SPICE simulations.
I agree with you that most models have difficulties with convergence.
Many of them are really over complicated and sometimes generated
by stupid programs or "roboters" and not by engineers.

I assume that the listed models will work with some tweaking
of the convergence parameters.

What simulator do you use?
If it's LTspice then send me your files and I will make
you a working example with your AD8605.
I always want to see the schematic, because I know that
people sometimes have errors in their circuit.
One important thing is to have a DC path to ground(0).


Best Regards,
Helmut
Moderator of the LTspice user group

hello folks, just saw your message about my Spice models. I did the
AD8605 model and would like to know what it is that you think isn't
working. I would prefer to see the test circuit you're using and
understand what you're trying to do. And if it really doesn't work,
then I owe you a pizza of your choice.

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

zineddine.zidane_at_gmail.com> schrieb im Newsbeitrag
news:1111772454.985113.86850_at_l41g2000cwc.googlegroups.com...
hello folks, just saw your message about my Spice models. I did the
AD8605 model and would like to know what it is that you think isn't
working. I would prefer to see the test circuit you're using and
understand what you're trying to do. And if it really doesn't work,
then I owe you a pizza of your choice.

Good morning Sir,
I posted 2h40m ago that this model has no problem.
Have you overlooked that or do you do you see postings only
after many hours? Please use a better news reader.
May news reader is uptodate within minutes.

Best Regards,
Helmut



My posting from 2h40m ago:

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

Hello Jim,
this wasn't necessary. This AD8605 model runs without any
convergence problem in LTspice. So the model doesn't have any error.
Yuu should withdraw your email to AD and apologize to the manager
you have contacted for any inconvenience. :)

Best Regards,
Helmut

hello folks, just saw your message about my Spice models. I did the
AD8605 model and would like to know what it is that you think isn't
working. I would prefer to see the test circuit you're using and
understand what you're trying to do. And if it really doesn't work,
then I owe you a pizza of your choice.






Helmut Sennewald wrote:
"Robert Baer" <robertbaer_at_earthlink.net> schrieb im Newsbeitrag
news:1PQ0e.3481$gI5.1145_at_newsread1.news.pas.earthlink.net...
The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps,
and found that almost all i tried gave me the same kind of
cryptic
square
root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the
only one
tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known
to work
(and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the
latter
of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web
just

yesterday - implying the problem is not fixed.

Can anyone help?

Hello Robert,
I don't believe that you really can judge the quality of these
models as a beginner with SPICE simulations.
I agree with you that most models have difficulties with
convergence.
Many of them are really over complicated and sometimes generated
by stupid programs or "roboters" and not by engineers.

I assume that the listed models will work with some tweaking
of the convergence parameters.

What simulator do you use?
If it's LTspice then send me your files and I will make
you a working example with your AD8605.
I always want to see the schematic, because I know that
people sometimes have errors in their circuit.
One important thing is to have a DC path to ground(0).


Best Regards,
Helmut
Moderator of the LTspice user group

"Robert Baer" <robertbaer_at_earthlink.net> schrieb im Newsbeitrag
news:1PQ0e.3481$gI5.1145_at_newsread1.news.pas.earthlink.net...

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail opamps,
and found that almost all i tried gave me the same kind of cryptic square
root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only one
tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to work
(and more or less correctly), but i need to get a working AD8605 model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?


Hello Robert,
I don't believe that you really can judge the quality of these
models as a beginner with SPICE simulations.
I agree with you that most models have difficulties with convergence.
Many of them are really over complicated and sometimes generated
by stupid programs or "roboters" and not by engineers.

I assume that the listed models will work with some tweaking
of the convergence parameters.

What simulator do you use?
If it's LTspice then send me your files and I will make
you a working example with your AD8605.
I always want to see the schematic, because I know that
people sometimes have errors in their circuit.
One important thing is to have a DC path to ground(0).


Best Regards,
Helmut
Moderator of the LTspice user group




Well, in a sense you are correct in labellling be as a beginner; i

On Fri, 25 Mar 2005 09:26:21 GMT, Robert Baer
robertbaer_at_earthlink.net> wrote:


The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605 model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?


Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.

I, personally, have experienced some problems with ADI models.
Reported same, and was told, "They work just fine here."

So don't hold your breath.

BTW, Sennewald is wrong when he says, "...generated by stupid programs
or "roboters" and not by engineers."

They ARE generated by engineers, or should I say it as "engineers"
?:-)

...Jim Thompson
I appreciate that you passed on the comments.

----- Original Message -----
From: "Jim Thompson" <thegreatone_at_example.com
Newsgroups: sci.electronics.cad
Sent: Friday, March 25, 2005 3:37 PM
Subject: Re: Problems with SPICE models from vendors



On Fri, 25 Mar 2005 09:26:21 GMT, Robert Baer
robertbaer_at_earthlink.net> wrote:


The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail
opamps, and found that almost all i tried gave me the same kind of
cryptic square root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only
one tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to
work (and more or less correctly), but i need to get a working AD8605
model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?

Problem noted, and forwarded to the appropriate device-modeling
manager at Analog Devices.


Hello Jim,
this wasn't necessary. This AD8605 model runs without any
convergence problem in LTspice. So the model doesn't have any error.
Yuu should withdraw your email to AD and apologize to the manager
you have contacted for any inconvenience. :)

Best Regards,
Helmut


Please tell me why it does not work (and others mentioned) and that

hello folks, just saw your message about my Spice models. I did the
AD8605 model and would like to know what it is that you think isn't
working. I would prefer to see the test circuit you're using and
understand what you're trying to do. And if it really doesn't work,
then I owe you a pizza of your choice.






Helmut Sennewald wrote:

"Robert Baer" <robertbaer_at_earthlink.net> schrieb im Newsbeitrag
news:1PQ0e.3481$gI5.1145_at_newsread1.news.pas.earthlink.net...

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail

opamps,

and found that almost all i tried gave me the same kind of cryptic

square

root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the

only one

tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known

to work

(and more or less correctly), but i need to get a working AD8605

model.

The sets i have came from the manufacturer created in the latter

of

1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just


yesterday - implying the problem is not fixed.

Can anyone help?

Hello Robert,
I don't believe that you really can judge the quality of these
models as a beginner with SPICE simulations.
I agree with you that most models have difficulties with convergence.
Many of them are really over complicated and sometimes generated
by stupid programs or "roboters" and not by engineers.

I assume that the listed models will work with some tweaking
of the convergence parameters.

What simulator do you use?
If it's LTspice then send me your files and I will make
you a working example with your AD8605.
I always want to see the schematic, because I know that
people sometimes have errors in their circuit.
One important thing is to have a DC path to ground(0).


Best Regards,
Helmut
Moderator of the LTspice user group


Here is a partial of the .OUT for the AD8614 which "works":

Helmut Sennewald wrote:
"Robert Baer" <robertbaer_at_earthlink.net> schrieb im Newsbeitrag
news:1PQ0e.3481$gI5.1145_at_newsread1.news.pas.earthlink.net...

The LM324 model from TI works fine,but the one from National
Semiconductor is junk.
I tried numerous Analog Devices models for various rail-to-rail opamps,
and found that almost all i tried gave me the same kind of cryptic square
root error.
Those tried: AD8605, AD531, AD541, AD8552, and the AD8571; the only one
tried that did work was for the AD8614.
Now i would dearly like to have a set of models that were known to work
(and more or less correctly), but i need to get a working AD8605 model.
The sets i have came from the manufacturer created in the latter of
1992, and thus are not quite up-to-date.
However, the model for the AD8605 was downloaded via the web just
yesterday - implying the problem is not fixed.

Can anyone help?


Hello Robert,
I don't believe that you really can judge the quality of these
models as a beginner with SPICE simulations.
I agree with you that most models have difficulties with convergence.
Many of them are really over complicated and sometimes generated
by stupid programs or "roboters" and not by engineers.

I assume that the listed models will work with some tweaking
of the convergence parameters.

What simulator do you use?
If it's LTspice then send me your files and I will make
you a working example with your AD8605.
I always want to see the schematic, because I know that
people sometimes have errors in their circuit.
One important thing is to have a DC path to ground(0).


Best Regards,
Helmut
Moderator of the LTspice user group




Well, in a sense you are correct in labellling be as a beginner; i
rarely use SPICE, but that useage has covered over 30 years.
When one models a simple voltage follower, with the NI input half way
between the poser supplies for the op-amp, one expects it to work, and
not give a cryptic square root error.
Furthermore, replacing the model used to a different one (eg replace
the call from the AD8605 to the AD8614 (and changing *nothing* else) and
have it work begs the question: what is wrong with the AD8605 model?
The same can be said about the models for the LM324; the TI model
works and the NatSemi does not.

And speaking of bad models that DO "work", the AD8614 is rather poor
(from the .OUT file):

.OPTIONS ACCT LIST NODE OPTS NUMDGT=6 RELTOL=0.00001 NOPAGE
.TEMP 27
.LIB ANLG_DEV.LIB ; most rail-to-rail opamps die with error
.DC VBAT 4.499 4.501 0.001
VBAT 01 00 DC 4.5
VSET 10 00 0.209171
VIN 05 00 0.018051
R2 05 07 18.4K
R3 10 08 18.4K
R4 09 07 100K
* NI I OUT
XAMP2 08 07 01 00 09 AD8614/AD
.PRINT DC V(05) V(07) V(0 V(09)
.PLOT DC V(05) V(07) V(0 V(09)
.SAVE

V(5) V(7) V( V(9)

1.80510E-02 2.22746E-01 2.21746E-01 1.26487E+00

Look at the poor results: large input currents, large Vos. Almost
useless; certainly not representative of the part.