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Re: AD8336 failure

Tony Casey
 

--- In LTspice@..., "stm6823@..." <stevemorris@...> wrote:

Tony,
Thanks for answering. I thought FILES&#92;AD8336 in my help request would indicate where all the files were. Is there another way I should have done it?
STM

--- In LTspice@..., "Tony Casey" <tony@> wrote:



--- In LTspice@..., "stm6823@" <stevemorris@> wrote:

When I try to run AD8336-2.asc in FILES&#92;AD8336 I get an error message that contains "Circuit: * C:&#92;Program Files&#92;LTC&#92;AD models&#92;AD8336&#92;AD8336-2.asc

WARNING: Node U1:U4_N24227 is floating."
But checking the .net file I do not find any NC.
Whats wrong?
Thanks in advance,
STM
Hello Steve,

Apologies for the earlier comment. I found your files in Files>Temp>AD8336, but there was no announcement or indication from you that they were there.

You schematic wouldn't run, but not due to the reason you gave. You had hard-coded the absolute path of the model file into the symbol, and of course when it is downloaded by someone else, it will, in general, not have the same path that you used. If you put the .included file into the .asc directory, you don't need any absolute path, as LTspice will always look there.

The error I got was "timestep too small... etc", which sometimes means the model is dodgy, but the schematic is probably at least syntactically OK.

I changed your schematic to something resembling the ADI application circuit, but still got a convergence error with an .op analysis, so I think the model file is the problem, but I'm afraid I don't have the time or inclination to debug it. Sorry.

Regards,
Tony
Hello STM,

It's possible I looked before the files were actually there, but when I found them they were in Files>Temp>AD8336, not Files>AD8336.

It's also helpful when uploading files, to check the box about making an announcement to the group with a comment, not least because that message will have the correct hyperlink to the uploaded file because it's autogenerated and not prone to user error.

I'm glad Helmut sorted you out, though, as he usually does when others fail.

Regards,
Tony


Re: Simple model for diffin-diffout amp

ehydra
 

Indeed, and that is the reason why I just use the datasheet and the universalopamp symbol to get rid of the problems. Most times the universalopamp makes a better job.

- Henry

--
ehydra.dyndns.info

RobertTalty schrieb:

The Microchip opamp spic models are very complex and attempt to model all types of errors and their Temp variations, but in the end these models cause convergence problems, so what is the point of a complex model that causes beginners convergence problems. Convergence can be hard for experienced spice users to solve, so it is the last thing that beginners need.
So if you want to see some complex models go to Microchip and download some of their spice models.


Re: AD8336 failure

 

Tony,
Thanks for answering. I thought FILES&#92;AD8336 in my help request would indicate where all the files were. Is there another way I should have done it?
STM

--- In LTspice@..., "Tony Casey" <tony@...> wrote:



--- In LTspice@..., "stm6823@" <stevemorris@> wrote:

When I try to run AD8336-2.asc in FILES&#92;AD8336 I get an error message that contains "Circuit: * C:&#92;Program Files&#92;LTC&#92;AD models&#92;AD8336&#92;AD8336-2.asc

WARNING: Node U1:U4_N24227 is floating."
But checking the .net file I do not find any NC.
Whats wrong?
Thanks in advance,
STM
Hello Steve,

Apologies for the earlier comment. I found your files in Files>Temp>AD8336, but there was no announcement or indication from you that they were there.

You schematic wouldn't run, but not due to the reason you gave. You had hard-coded the absolute path of the model file into the symbol, and of course when it is downloaded by someone else, it will, in general, not have the same path that you used. If you put the .included file into the .asc directory, you don't need any absolute path, as LTspice will always look there.

The error I got was "timestep too small... etc", which sometimes means the model is dodgy, but the schematic is probably at least syntactically OK.

I changed your schematic to something resembling the ADI application circuit, but still got a convergence error with an .op analysis, so I think the model file is the problem, but I'm afraid I don't have the time or inclination to debug it. Sorry.

Regards,
Tony


Diode Model Request for 1N5811 and 1N6628

 

Could someone let me know where I can find spice models for both 1N5811 and 1N6618? I was unable to locate them in the on-line library.

Thanks,

Dan


Diode Model Request for 1N5811 and 1N6628

 

Could someone let me know where I can find spice models for both 1N5811 and 1N6618?
?
Thanks,
?
Dan

[Non-text portions of this message have been removed]


Re: adding noise to the model of a sensor

 

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:



--- In LTspice@..., "rug_rossi" <rrossi@> wrote:

I need to add a noise generator to the model of a sensor
(simply a behavioral source), in order to perform some
noise analysis.

Noise is described by a noise density and a 1/f corner.

which is the best way to do that?
Add to my model a voltage follower made with the
Universal OP amp level 1, or there is a better way?

best regards,

Ruggero Rossi
Hello Ruggero,

The 1/f noise is implemented in diodes. Thus diode noise may be
the natural choice for an 1/f noise source.

Files > Tut > noisegen
Files > Tut > noisegen_with_subcircuits
Files > Tut > new_diode_noise.asc


You already mentioned the "universalopamp". It contains
parameters en and enk to set noise value and corner frequency.

Best regards,
Helmut
Thank you,

noisegen.asc + noisegen.asy is what I needed!

Ruggero


Re: About impedance

 

What is the purpose of Cartesian plot? I'm sure it makes some things more convenient than a bode plot. What things?

- keantoken


Re: About impedance

 

Dear Helmut,
?
Thank you very much for your quick response.
Yes, I was doing .AC simulation.
?
Sincerely,
?
Mahmudul Kabir, Japan?


--- In LTspice@..., Mahmudul Kabir <nilonjana@...> wrote:

Dear Members,
?
Is there any chance to calculate of real or imaginary part
of impedance while doing a simulation?with any AC voltage?
?
Or is it possible to draw?a trace of real part or imaginary
part of impedace in LTspice?
?
Thank you in advance,
?
Mahmudul Kabir, Japan
Hello Mahmudul Kabir,

I assume you use .AC simulation. In this case you can plot
in Cartesian format which shows the real part with a solid
line and the imaginary part with a dashed line.

Best regards,
Helmut




[Non-text portions of this message have been removed]


Re: Hey i am working on a Class D amp project, need help about LT Spice

John Woodgate
 

In message <j4sde1+lkfq@...>, dated Thu, 15 Sep 2011, cukkacan <mustafa_cukka@...> writes:

Hey, i am sophomore at the university, and i have a circuit sketch and data sheet. However, i dont know how to use LT Spice effectively. i couldnt build the circuit on LT Spice perfectly. Could you help me about this issue ?
Study the examples and tutorials available on the list's web site. Read the Help. Upload your non-working schematic to the web site Files -> Temp and tell us you've done it.

Also, advices about Class D amp are welcome. i need a working class-d amp circuit about 10-20W.i have checked on the web, topics are not live.
This list is not a general design help list. A web search for 'Class D' will provide you with hundreds of good hits (and some bad ones, but you can't win them all).
--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
When I point to a star, please look at the star, not my finger. The star will
be more interesting.


Re: About impedance

 

--- In LTspice@..., Mahmudul Kabir <nilonjana@...> wrote:

Dear Members,
?
Is there any chance to calculate of real or imaginary part
of impedance while doing a simulation?with any AC voltage?
?
Or is it possible to draw?a trace of real part or imaginary
part of impedace in LTspice?
?
Thank you in advance,
?
Mahmudul Kabir, Japan
Hello Mahmudul Kabir,

I assume you use .AC simulation. In this case you can plot
in Cartesian format which shows the real part with a solid
line and the imaginary part with a dashed line.

Best regards,
Helmut


Re: adding noise to the model of a sensor

 

--- In LTspice@..., "rug_rossi" <rrossi@...> wrote:

I need to add a noise generator to the model of a sensor
(simply a behavioral source), in order to perform some
noise analysis.

Noise is described by a noise density and a 1/f corner.

which is the best way to do that?
Add to my model a voltage follower made with the
Universal OP amp level 1, or there is a better way?

best regards,

Ruggero Rossi
Hello Ruggero,

The 1/f noise is implemented in diodes. Thus diode noise may be
the natural choice for an 1/f noise source.

Files > Tut > noisegen
Files > Tut > noisegen_with_subcircuits
Files > Tut > new_diode_noise.asc


You already mentioned the "universalopamp". It contains
parameters en and enk to set noise value and corner frequency.

Best regards,
Helmut


About impedance

 

Dear Members,
?
Is there any chance to calculate of real or imaginary part of impedance while doing a simulation?with any AC voltage?
?
Or is it possible to draw?a trace of real part or imaginary part of impedace in LTspice?
?
Thank you in advance,
?
Mahmudul Kabir, Japan
?

[Non-text portions of this message have been removed]


Re: AD8336 failure

 

--- In LTspice@..., "stm6823@..." <stevemorris@...> wrote:

When I try to run AD8336-2.asc in FILES&#92;AD8336 I get an error message that contains "Circuit: * C:&#92;Program Files&#92;LTC&#92;AD models&#92;AD8336&#92;AD8336-2.asc

WARNING: Node U1:U4_N24227 is floating."
But checking the .net file I do not find any NC.
Whats wrong?
Thanks in advance,
STM

Hello STM,

I have corrected your symbol and the schematic. It has been
also necessary to add some convergence help.
It has required the critical option

.options cshunt=1e-15

I have uploaded a working example.

Files > Temp > AD8336 > AD8336_1.zip.

Best regards,
Helmut


adding noise to the model of a sensor

 

I need to add a noise generator to the model of a sensor (simply a behavioral source), in order to perform some noise analysis.

Noise is described by a noise density and a 1/f corner.

which is the best way to do that?
Add to my model a voltage follower made with the Universal OP amp level 1, or there is a better way?

best regards,

Ruggero Rossi


Hey i am working on a Class D amp project, need help about LT Spice

cukkacan
 

Hey, i am sophomore at the university, and i have a circuit sketch and data sheet. However, i dont know how to use LT Spice effectively. i couldnt build the circuit on LT Spice perfectly. Could you help me about this issue ?

Also, advices about Class D amp are welcome. i need a working class-d amp circuit about 10-20W.i have checked on the web, topics are not live.


Re: Implementing BSS138 spice model

 

--- In LTspice@..., "pindsen" <windven@...> wrote:

Hi,

I need an BSS138 in my LTSpice simulation.
Since I can't find that component in the program itself, I need to make it.

I have done the following steps but LTspice won't simulate:

1) Downloaded a Zetex BSS138 spice subcircuit and placed it in a "BSS138.sub" file
2) The spice file is placed in c:&#92;program files&#92;LTC&#92;LTspiceIV&#92;lib&#92;sub
3) Included a nmos symbol (nmos.asy) in the design
4) Renamed the symbol to BSS138/ZTX
5) Add a spice directive command ".inc BSS138.sub"
6) Hit the run button
7) LTspice can't simulate and says "Can't find definition of model "bss138".

The Zetex spice model can be seen here:

*ZETEX BSS138 Spice Mosfet Subcircuit Last revision 11/91
*
.SUBCKT BSS138/ZTX 3 4 5
* Nodes D G S
M1 3 2 5 5 MOD1
RG 4 2 343
RL 3 5 6E6
D1 5 3 DIODE1
.MODEL MOD1 NMOS VTO=1.109 RS=1.474 RD=1.59 IS=1E-15 KP=0.597
+CGSO=23.5P CGDO=4.5P CBD=53.5P PB=1 LAMBDA=267E-6
.MODEL DIODE1 D IS=1.254E-13 N=1.0207 RS=0.222
.ENDS

Can anyone help?

Best regards
Carsten Wind
Denmark
Hello Carsten,

4a)
Ctrl-right-mouse-click on the placed symbol nmos.
Change Prefix:MN to Prefix:X

2) I always recommend to save model files in the folder of the
schematic.

Best regards,
Helmut


Implementing BSS138 spice model

 

Hi,

I need an BSS138 in my LTSpice simulation.
Since I can't find that component in the program itself, I need to make it.

I have done the following steps but LTspice won't simulate:

1) Downloaded a Zetex BSS138 spice subcircuit and placed it in a "BSS138.sub" file
2) The spice file is placed in c:&#92;program files&#92;LTC&#92;LTspiceIV&#92;lib&#92;sub
3) Included a nmos symbol (nmos.asy) in the design
4) Renamed the symbol to BSS138/ZTX
5) Add a spice directive command ".inc BSS138.sub"
6) Hit the run button
7) LTspice can't simulate and says "Can't find definition of model "bss138".

The Zetex spice model can be seen here:

*ZETEX BSS138 Spice Mosfet Subcircuit Last revision 11/91
*
.SUBCKT BSS138/ZTX 3 4 5
* Nodes D G S
M1 3 2 5 5 MOD1
RG 4 2 343
RL 3 5 6E6
D1 5 3 DIODE1
.MODEL MOD1 NMOS VTO=1.109 RS=1.474 RD=1.59 IS=1E-15 KP=0.597
+CGSO=23.5P CGDO=4.5P CBD=53.5P PB=1 LAMBDA=267E-6
.MODEL DIODE1 D IS=1.254E-13 N=1.0207 RS=0.222
.ENDS

Can anyone help?

Best regards
Carsten Wind
Denmark


Re: General SPICE environment setup

 

Dear Sir,
Will you please tell us how to do it? There might be cases when it is not such a bad idea.
Best Regards
E.A.Neonakis

--- In LTspice@..., "analogspiceman" <analogspiceman@...> wrote:


You can more or less do this now if you know how,


Re: What changes would make LTspice better?

martin562284
 

--- In LTspice@..., "Tony Casey" <tony@...> wrote:

Incidentally, the registry hack method works for almost any kind of file association, and can usefully be employed to invoke the a native Linux PDF reader, for example, from within many Windows applications (running in wine) that can call PDF files, instead of using a Windows version installed in the same wine bottle.
Thanks for that, although I use the Linux version of the Adobe reader for viewing PDFs. and LTspice is now the only Windows app that I use on a regular basis.

However, I'd like to try it on .net, .cir and .log files - I don't like the appearance of Notepad (purely a personal thing) so I'll try setting up an association to use the native editor of my choice.

Cheers,

Martin


Re: General SPICE environment setup

Jim Wagner
 

On Sep 14, 2011, at 10:24 PM, martin562284 wrote:



--- In LTspice@..., "analogspiceman"
<analogspiceman@...> > You can more or less do this now if you know
how, but it is a
really bad idea
Well, I wouldn't go so far as to say "really bad", just undesirable.
But that's precisely why I'd like to have the facility to have an
optional (with the emphasis on "optional") intermediate directory
hierarchy - something akin to the Windows/Linux $PATH environment
variable principle....

unless you are certain you will never need to share
your work with anyone else
As I'm a one-man band, sadly I very rarely have the need/opportunity
to share with others, but see below...

(including with yourself when you are
on another computer at a later date trying to go back and recreate
your now-forgotten wonder design).
I regularly (almost daily) move between two or three PCs and, with
the aid of Unison, have no problem in keeping all my stuff in sync.

I'm not so presumptuous as to consider my designs "wonderful", but
for the most part they work sufficiently well to meet my needs and I
have some simple but effective, tried and tested processes for
keeping track of them and the third-party models I use...

To share successfully, you will
have to hunt down all your custom components and symbols that you
have made to appear to *you* as just another part of standard
LTspice.

Keeping all user project files in a dedicated folder for each
project allows you to easily recognize and zip together all your
custom work for run-out-of-the-box sharing.
Most of my projects use non-standard (ie. not provided in the
standard LTspice release) models, subs or libs, not just of my own
design but also third-party models, libraries and subs. I don't want
to keep multiple copies of these in each project directory as it
gives me a version control headache. Anything which is project-
specific stays in the project directory.

It's the stuff that I use time and time again that I want to find a
home for, preferably separate from the LTspice lib directory, which
is what my suggestion is all about. This would apply to models, also
- at present LTspice has the facility to add third-party models into
the standard.* files (ref. scad3.pdf, p187, para 3c) - I believe it
would also be better to keep these separate.

Unless Mike were to
a "Ferret & Zip" tool that discretely bundled up all your dangling
custom bits with a single button click, this idea is better left
as an unfulfilled wish. -- a.s.
I neither expect nor need Mike to provide any such tool - I'm happy
to look after that for myself. It's actually quite simple. Due to
the elegance of LTspice's file formats, all the information is
readily available. I'd be more than willing to assist in producing
an "official" tool, should the opportunity arise.

I'm not demanding nor even requesting that you or anyone else change
your way of working, I'm just requesting a facility to give me, and
any one else who wishes it, the freedom to work in the way we
choose. In the meantime, I'm happy to share my experience with
others who wish to tread the same path.

I really do agree with Martin. The simple idea that one way fits all
is simply not productive. Many of us have different styles of file
management. The idea that our user environment must be exactly that
which facilitates sharing over the internet is constraining. And, it
is really at odds with the idea of giving the user many ways to hang
him or her self. If we need to share a design, then why not a "share
design" or "export" menu item that packages all of the needed files
together and zips them in an appropriate hierarchy of folders (and
adjusts directive-based model references)?

The inclusion of a "project file" that references all of the project
files would make file management quite straight forward. I am really
quite surprised that such a strategy has not been adopted. It need not
get in the way of using legacy netlists or model files. After all,
virtually every software development environment allows inclusion of
library files of all sorts. LTspice need not be any different!

Jim Wagner
Oregon Research Electronics

[Non-text portions of this message have been removed]