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Are you still having problems after replacing the opamp with the generic
type?

Le 02/08/2013 11:08, resetpin a écrit :

Hi,

I uploaded the files into files/temp folder.

hope someone can give me a hint

Thanks in advance

Resetpin

--- In LTspice@... <mailto:LTspice%40yahoogroups.com>,
"resetpin" <resetpin@...> wrote:

Hello,

I used Filter Pro from Texas instruments to get a Filter design from

my specifications. They are:

Gain: 5V/V (13,97dB)
Part: Ideal Opamp: Order 4 Stages: 2
Corner frequency Attenuation: 10,979dB
Allowable PassBand Ripple 1dB
Center Frequency: 1,75 kHz
Stopband Attenuation: -30dB
Passband Bandwidth: 100Hz
Stopband Bandwith: 600Hz

Filterpro proviced a schematic and Values for the parts and a

Gain-Frequency plot.

When I try to redo this in LTSpice the frequency corner freqency of

the filter is at the right positon but the gain is about -40db.

I wonder where the differences are and would like to show the

LTSpice *.asc File compared with the Texax Results but don't know how
to post them here in the group.

Maybe someone is willing to help me out and show me the differences

or the problem.

Thanks in advance

Resetpin

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

Thanks Helmut,
I'll write to Mike.
Let's see, your solution (..speaker.lib) would require that the netlists of my models be placed in a .lib text file, yes? That would prohibit the viewing of the parts schematics by right-clicking on their symbol in the top level schematic, yes? If I'm wrong, please let me know!

rgds,
Andy

Hmm, I reworked my way through the files directory and it worked this time.

When I try to download any of the files from I get a document not found message. Any ideas?

Hi Andy / Helmut

Ive had a similar issue, example:

I put my libs into:
c:&#92;users&#92;username&#92;LTspice4&#92;lib

My ckt sub dirs are just below
c:&#92;users&#92;username&#92;LTspice4

c:&#92;users&#92;username&#92;LTspice4&#92;cktname

Then i use .include ..&#92;lib&#92;libname.lib
up one dir and down into the lib dir for the lib files / search.
That way i can have all of my models / subckts in one place.

Doesnt for for symbols :-(
they still want to be in the program files path.

Al D.

--


AC2CL

I do not think there is any thrill that
can go through the human heart like that felt by the inventor as
he sees some creation of the brain unfolding to success...
Such emotions make a man forget food, sleep, friends, love, everything.

- Nikola Tesla

--- In LTspice@..., "a2n14d63y" <andydraudt@...> wrote:

Hi All,
I'm new and trying to migrate from Msim Pspice over to LTspice. My big problem is with part libraries and directory search paths.

I do electro-mechanical-acoustic (thermal?) lumped element models using spice, and have many schematics I've made for parts (e.g. combustion model, speaker, alternator, nonlinear springs etc.). These get added to designs of larger systems.

In Pspice I could put my models into a directory and tell the program where to look for those parts. This is convenient, since my system-level projects were in many different project directories, and it would be absurd to copy all my part schematic files (about 50 parts) into each project directory. It seems that is not possible in LTspice, and I'd have to dump all my parts into the "sub" directory of the LT install tree?

So, my question is - are there plans to allow LTspice to address schematics stored in directories other than the current one or the LT install tree?

Thanks!
-Andy

p.s. I want the parts to remain as schematics, rather
than being just stored as netlists in a lib, because
they need to be graphically presented and tweaked regularly.

Hello Andy,

If you don't need that everybody can run your designs out
of the box, you could use an absolute path for your includes.

.lib C:&#92;mymodels&#92;speaker&#92;speaker1.lib

I admit that this is not a really good solution.
You could send an email to Mike with your wish. His email
address is given in the Help -> About of the LTspice program.

Best regards,
Helmut

Hi All,
I'm new and trying to migrate from Msim Pspice over to LTspice. My big problem is with part libraries and directory search paths.

I do electro-mechanical-acoustic (thermal?) lumped element models using spice, and have many schematics I've made for parts (e.g. combustion model, speaker, alternator, nonlinear springs etc.). These get added to designs of larger systems.

In Pspice I could put my models into a directory and tell the program where to look for those parts. This is convenient, since my system-level projects were in many different project directories, and it would be absurd to copy all my part schematic files (about 50 parts) into each project directory. It seems that is not possible in LTspice, and I'd have to dump all my parts into the "sub" directory of the LT install tree?

So, my question is - are there plans to allow LTspice to address schematics stored in directories other than the current one or the LT install tree?

Thanks!
-Andy

p.s. I want the parts to remain as schematics, rather than being just stored as netlists in a lib, because they need to be graphically presented and tweaked regularly.

That did it! Thanks.

a simple 1e6*V(inoise)/1V*sqrt(1Hz) does make the plot 'dimensionless' with magnitudes in the expected range

Small remaining point, if I try to shift the plot by adding, doesn't work as expected.
for example,
1e6*V(inoise)/1V*sqrt(1Hz)
and then
1e6*V(inoise)/1V*sqrt(1Hz)+10
does NOT shift the display upwards by 10 instead shifts upward by sqrt(sum(squares)), which makes sense, but doesn't do exactly what I expected.

even adding parantheses to offset the calculation
(1e6*V(inoise)/1V*sqrt(1Hz)) +10
still maintains the sqrt(sum)

not a deal breaker, just interesting.


--- helmutsennewald@... wrote:

From: "Helmut" <helmutsennewald@...>
To: LTspice@...
Subject: [LTspice] Re: How to change plot dimensions?
Date: Fri, 02 Aug 2013 14:49:49 -0000



--- In LTspice@..., Macy <macy@...> wrote:

Plot noise vs frequency and the plot comes out in dimensions of
V/sqrt(Hz)
which is correct.

However, in my circuit I would like to have it plot in another dimensions [same number value, different name]

How to change?

I successfully get rid of V by dividing by 1V, but there doesn't seem to be any equivalent to get rid of sqrt(Hz)

Anybody made a noise plot 'dimensionless'?

Hello Macy,

I didn't know how it works before. I tried and had luck.

V(onoise)*sqrt(1Hz)

Best regards,
Helmut

--- In LTspice@..., jude thad <jukwai3@...> wrote:

Thanks Helmut and Joubert for ur quick response.

I did save in other folder and it was good except that i have
another challenge.
The simulator says the "time set up is too small"...how
could that be solved?

Hello Jude,

The problem can be a mistake in the circuit or the models.

You could try the following SPICE-directives.

.options gmin=1e-10

.options gmin=1e-10 abstol=1e-10

.options gmin=1e-10 abstol=1e-10 reltol=0.003

Additionally try with the "dangerous" capacitor option.

.options cshunt=1e-16


If this doesn't help, try the Alternate solver.

Control Panel -> SPICE-> Solver:Alternate


Best regards,
Helmut

Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands


________________________________
From: Helmut <helmutsennewald@...>
To: LTspice@...
Sent: Friday, August 2, 2013 3:14 PM
Subject: [LTspice] Re: Importing Spice Models



??


--- In LTspice@..., jude thad <jukwai3@> wrote:

Hello All,

I am trying to import spice model for LM339 into LTspice. When I tried saving the spice model on the LTC/LTspice/lib/sub, I was told I am not allowed to save in that directory, that I need administrative permission before I could do that. Please could any one give me some ways out?

Am very grateful!

Thanks in advance!

??
Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands

Hello,

The best place for the model file is the folder where you
have the schematics using this model. Don't save any of
your designs in the WIN system folders like C:&#92;Program files
Instead make a folder like C:&#92;mycircuits&#92; for your designs.
If you need a model in more designs, then copy the model
files into all the folders of these designs.

Best regards,
Helmut

Hi All,

Thanks for the basic physics reminder and the other thread dealing with this issue!

Cheers,
Darren

--- In LTspice@..., Robert Macy wrote:

Plot noise vs frequency and the plot comes out in dimensions
of V/sqrt(Hz), which is correct. However, in my circuit I would
like to have it plot in another dimensions (same number value,
different name). How to change?

I successfully get rid of V by dividing by 1V, but there doesn't
seem to be any equivalent to get rid of sqrt(Hz)

Anybody made a noise plot 'dimensionless'?

Haven't tested it, but have you tried dividing the waveform
expression in question by sqrt(1Hz), by 1Hz**0.5 or perhaps by
something like pwr(1Hz,0.5)?

--- In LTspice@..., Macy <macy@...> wrote:

Plot noise vs frequency and the plot comes out in dimensions of
V/sqrt(Hz)
which is correct.

However, in my circuit I would like to have it plot in another dimensions [same number value, different name]

How to change?

I successfully get rid of V by dividing by 1V, but there doesn't seem to be any equivalent to get rid of sqrt(Hz)

Anybody made a noise plot 'dimensionless'?

Hello Macy,

I didn't know how it works before. I tried and had luck.

V(onoise)*sqrt(1Hz)

Best regards,
Helmut

Plot noise vs frequency and the plot comes out in dimensions of
V/sqrt(Hz)
which is correct.

However, in my circuit I would like to have it plot in another dimensions [same number value, different name]

How to change?

I successfully get rid of V by dividing by 1V, but there doesn't seem to be any equivalent to get rid of sqrt(Hz)

Anybody made a noise plot 'dimensionless'?

Thanks Helmut and Joubert for ur quick response.

I did save in other folder and it was good except that i have another challenge.
The simulator says the "time set up is too small"...how could that be solved?



Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands


________________________________
From: Helmut <helmutsennewald@...>
To: LTspice@...
Sent: Friday, August 2, 2013 3:14 PM
Subject: [LTspice] Re: Importing Spice Models



?


--- In LTspice@..., jude thad <jukwai3@...> wrote:

Hello All,

I am trying to import spice model for LM339 into LTspice. When I tried saving the spice model on the LTC/LTspice/lib/sub, I was told I am not allowed to save in that directory, that I need administrative permission before I could do that. Please could any one give me some ways out?

Am very grateful!

Thanks in advance!

?
Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands

Hello,

The best place for the model file is the folder where you
have the schematics using this model. Don't save any of
your designs in the WIN system folders like C:&#92;Program files
Instead make a folder like C:&#92;mycircuits&#92; for your designs.
If you need a model in more designs, then copy the model
files into all the folders of these designs.

Best regards,
Helmut




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

--- In LTspice@..., Andy <Andrew.Ingraham@...> wrote:

I never remember PSPICE being named or referred to as uPSPICE. As far as I
knew, it had always been PSPICE.

I also thought the 'P' was analogous to PC (personal computer) ... not
whether the CPU in that computer was a microprocessor. It was one of the
first attempts to make SPICE "personally" available directly to the user,
in the same way the PC made computers personal.

(Strangely, PSPICE later was ported to mainframes or large minis too.)

Earlier, someone commented that the offshoots to SPICE came about as a
result of the GUI. I suggest that it wasn't the GUI, but rather the PC
itself, that helped the various descendants of Berkeley's SPICE come about.
PSPICE (at least) came well before MS-Windows had made any headway, maybe
even before Windows existed, and that is what we generally think of when
talking about a GUI. Prior to that, the GUI on a PC was text and keyboard
based, though a program could turn on and manage graphics modes if it had
the code to do so. That was the environment into which PSPICE was born.

(I have run PSPICE occasionally but for various reasons it was never my
main work platform.)

Andy


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

I am still in occasional contact with several of the original support team back when PSpice was Microsim. One of them is Charlie Edmondson, a regular on S.E.D. I'll ask around.

-Jim Thompson

--- In LTspice@..., jude thad <jukwai3@...> wrote:

Hello All,

I am trying to import spice model for LM339 into LTspice. When I tried saving the spice model on the LTC/LTspice/lib/sub, I was told I am not allowed to save in that directory, that I need administrative permission before I could do that. Please could any one give me some ways out?

Am very grateful!

Thanks in advance!

?
Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands

Hello,

The best place for the model file is the folder where you
have the schematics using this model. Don't save any of
your designs in the WIN system folders like C:&#92;Program files
Instead make a folder like C:&#92;mycircuits&#92; for your designs.
If you need a model in more designs, then copy the model
files into all the folders of these designs.

Best regards,
Helmut

Hello All,

I am trying to import spice model for LM339 into LTspice. When I tried saving the spice model on the LTC/LTspice/lib/sub, I was told I am not allowed to save in that directory, that I need administrative permission before I could do that. Please could any one give me some ways out?

Am very grateful!

Thanks in advance!

?
Met Vriendlijke groeten/ Kind Regards,
Jude Anizoba
Fontys University of applied Science,
Eindhoven,The Netherlands

Thanks Helmut for your answer!

Regards
Sergio

Thanks a lot for your fast reply, the negative supply voltage was the solution.

Thanks

Resetpin

I replaced the opamp with the "standard" opamp (the one without supply
pins) and LTSpice gives the same results as TI.