On Thu, Mar 13, 2025 at 06:04 AM, John Waugaman wrote: The original LM321 (as well as the LM121 and LM221) is described as a
"Precision Preamplifier" in the 1976 to 1982 linear data books, Hello to all, I have looked into my NSC documents and in this threat about LM121/LM221/LM321: 1972 (none) 1976 LM121/LM221/LM321 Precision Amplifier 1980 LM121/LM221/LM321 Precision Amplifier 1988 LM221/LM321 Precision Amplifier 1995 LM221/LM321 Precision Amplifier 1999 (none) 2001 LM321 Single Op Amp The "Precision Amplifier" documentation was published for about 20 years. Between 1980 and 1988 the LM121 version (-55...125 °C) was discontinued. In April 2001 the Single Op Amp appeared. But a few years earlier LMV321 and LPV321 (single versions of LMV324 resp. LPV324) were published. In 2011 National Semiconductor became part of Texas Instruments. In addition I have just uploaded a 1995 version of NSC AN-79 "IC Preamplifier Challenges Choppers on Drift" - LM121, 1973-02 graphical update 1995. I did not find any difference to the former versions but the quality is a bit better e.g. the LM121 chip foto and scalable text (no pixel scan) Bernhard
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Re: Schematic shows different sized text
On Thu, Mar 13, 2025 at 04:14 PM, <charles@...> wrote:
My file is AC_Coupling.asc ...
Ah.? That was your way of telling us that you uploaded that file.? In the future, please make it a little more obvious, so that even slow people like me notice it.
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Indeed, it looks like it was?saved more than a decade ago, before Mike Engelhardt changed LTspice's "default" font size.? The result is that some of the text now looks tiny - and some doesn't.
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I ran it through LTspice with the 'FixUpSchematicFonts command-line switch, and saved it as "AC Coupling FixedFonts.asc" in the "Temp" folder.
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Andy
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Re: Schematic shows different sized text
On Thu, Mar 13, 2025 at 04:14 PM, <charles@...> wrote:
My file is AC_Coupling.asc and has text that has been made smaller than it was in older LTSpice versions. The weird part is some text is small but other text is normal. Using version 24.0.12.
Is there a question in there?
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Most text on LTspice schematics can be changed to different sizes.
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There is the global setting, in the Control Panel (Settings) > Drafting Options > Font Properties > Size.? That setting would affect the difference between text, and symbols and wires.? In my opinion, it is best left alone, or else you may end up with schematics that are unreadable when viewed by other LTspice users.
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And then there is the relative text size setting, for some but not all types of text.? You can change the relative size of comment text, as well as text that is attached to symbols, but not Labels (net names).? Right-click on the text and look for "Font Size".? The choices probably are 0.625, 1.0, 1.5(default), 2.0, 2.5, 3.5, 5.0, and 7.0.? These can be used to scale individual texts up or down in size.
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If you created schematics in VERY old versions of LTspice (probably LTspice III which was MANY years ago), then the text might have been saved differently in the .asc file, causing their text to look tiny when the schematic is opened in newer versions (LTspice IV, LTspice XVII, or LTspice 24).? LTspice has two command-line switches (-FixUpSymbolFonts and -FixUpSchematicFonts) to "repair" those old schematics or symbols that had that problem.? See the Help page for Modes of Operation > Command Line Switches.
Andy
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Re: Schematic shows different sized text
Yes, this is known about, and it's a nuisance.
There is a file that fixes it, but it has to be run from the
command line. Instead, you can click on each small text (use the
magnifier (plus sign on the toolbar) if necessary and rest the
size to 1.5, which is the default.
My file is AC_Coupling.asc and has text that has been made
smaller than it was in older LTSpice versions. The weird part is
some text is small but other text is normal. Using version
24.0.12.
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
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Schematic shows different sized text
My file is AC_Coupling.asc and has text that has been made smaller than it was in older LTSpice versions. The weird part is some text is small but other text is normal. Using version 24.0.12.
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Re: Schematic drawing issues
Just reporting that in 24.1.5, and using my 65 inch 4k screen....
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When adding a wire, I can very faintly see the extended crosshairs and cursor.
So faintly are the crosshairs that LTspice 24.1.5 is unusable with my 65 inch screen.
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I can see the cursor as long as I don't add a wire.
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Typo alert.??I wrote:
...? It's about a million times easier than combing through 20 years of scattered models, ...
Andy
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Re: Issue with Nexperia BUK7S1R0-40H PET LTspice model
I just uploaded "BUK7S1R0-40H with 2019 model.zip" to the Temp folder.
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Andy
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Re: Issue with Nexperia BUK7S1R0-40H PET LTspice model
Since the model is a .SUBCKT with 3 pins, and the symbol has 3 pins, I conclude that the most likely cause of the problem is user-error (cockpit error).? You did something wrong.? Try again.
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Andy
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FYI, by looking at a diode model, you can't tell how it performs.? You would need to do several simulations of each and every diode model, to extract the data you are looking for.
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Much, MUCH easier to just look at the table that is already built into LTspice itself.
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Andy
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As a first step, did you try searching through all the diode models that come with LTspice itself?
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It has them all collected together already, in a format that makes it simple to search for near-equivalents.? It's about a million times easier than coming combing through 20 years of scattered models, and somehow figuring out what characteristics you want to search for and how to do that.
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Andy
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Thank you very much, that's what I was afraid of.
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No, you can't use it. If TI will not supply an
unencrypted model (probably because the device uses a secret
trick), you can get TI's PSPICE for free, and run the simulation
in that.? The chances of finding a model elsewhere are very low.
On 2025-03-13 10:49, Tino B?hme via
groups.io wrote:
Hello,
I would like to use the LMR51606 in LTSpice.
I
only found an encrypted PSpice library on TI.
I've
already uploaded the file (LMR51606.zip).
Unfortunately,
I can't import the file into LTSpice.
Is
there a way to use the model, or does anyone have
one?
?
Thank
you.
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
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Hello, I would like to use the LMR51606 in LTSpice.
I only found an encrypted PSpice library on TI. I've already uploaded the file (LMR51606.zip).
Unfortunately, I can't import the file into LTSpice.
Is there a way to use the model, or does anyone have one?
?
Thank you.
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Re: Chan model for saturable transformer LTSPICE simulation
#Transformer
Your transformer model is not correct. You have also set a very high voltage for such a small core. Here is my transformer model. See the file NonLinearTransformer_pulse_AB2.zip in the TEMP folder.
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On 13/03/2025 10:37, thereitis via
groups.io wrote:
thanks for the reply.
?
since ltspice community has built by now a massive list of
diodes, and similarly with components that include the ones
provided by ltspice itself, i think we must have a software tool
that can use this database to provide search facilities.
?
in this regard, if i find a few people here, we can jointly
start working on an open-source tool for the same. we can start
working on it fro? scratch if necessary, but diode and
transistors can be a starting point.
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request to reply if interested anyone.
If you do a search of the Files area of this group's site with the
term "diode model", you will get 610 hits. Not all of them are
actual diode models, but some of them are. If you are more specific
with a device name, your hit rate will be better.
It's not actually that difficult to make a diode model yourself, and
there is already a semi-automatic model generator in the files area
too. It's not perfect, but model it produces are as good as many
manufacturers' models. It's also fairly easy to do this in a
spreadsheet (I have one).
A key thing to remember with surfing for models, is that there is no
guarantee they are accurate - many you find are anonymous, and
manufacturers' models are not always good. The onus is always on the
user to verify the models they use.
--
Regards,
Tony
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thanks for the reply.
?
since ltspice community has built by now a massive list of diodes, and similarly with components that include the ones provided by ltspice itself, i think we must have a software tool that can use this database to provide search facilities.
?
in this regard, if i find a few people here, we can jointly start working on an open-source tool for the same. we can start working on it fro? scratch if necessary, but diode and transistors can be a starting point.
?
request to reply if interested anyone.
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Re: Issue with Nexperia BUK7S1R0-40H PET LTspice model
That error message sometimes appears when
there is quite a different problem. It probably doesn't happen
often enough for tracking down the reason and fixing it to be
worthwhile. Examine your .ASC carefully, and check the
attributes of all the components.
I wish the error message could be a bit more
informative, by giving the numbers of pins, like this:
Port(pin) count mismatch between the definition of subcircuit
"buk7s1r0-40h" (3 pins) and instance "xu1" (2 pins)
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
|
Many manufacturers have diode equivalency charts, or part selector guides, on their websites.? ?You can parameterize your searches and come up with similar parts according to some criterion.
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Have you tried that?
?
If you could not find any, try harder.
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They might be less common for simple parts such as diodes (versus ICs), but I can assure you they do exist.
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Andy
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Re: Issue with Nexperia BUK7S1R0-40H PET LTspice model
On 13/03/2025 09:16, MaticH via
groups.io wrote:
I also tried using
older LEVEL = 3? NMOS model by nexperia, with 3 pins. But no luck
there either. I get Port(pin) count mismatch between the
definition of subcircuit "buk7s1r0-40h" and instance "xu1" error.
Even if both subcircuit and component have 3 pins. Anybody knows
what could be wrong here ??
If you want a definitive diagnosis, you would have to upload your
schematic together with all symbols and models in a zip to Files
> Temp.
--
Regards,
Tony
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John Woodgate
Tony Casey