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Re: LTspice 24.1.7 program exit

 

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It doesn't crash version 24.0.11, but it's a nonsense .ASC, isn't it? LTspice can't find I1, presumably because it's shorted.

On 2025-04-26 18:56, eetech00 via groups.io wrote:
The following circuit configuration was unintentional, but caused an LTspice program exit upon simulation run.
?
* Generated by LTspice 24.1.7 for Windows.
I1 0 0 1m
D1 0 0 D
V1 ADJ 0 0
.model D D
.lib (path removed)\standard.dio
.dc I1 2u 2m 100n
.backanno
.end
?
--
Best wishes John Woodgate RAYLEIGH Essex 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

Virus-free.


LTspice 24.1.7 program exit

 

The following circuit configuration was unintentional, but caused an LTspice program exit upon simulation run.
?
* Generated by LTspice 24.1.7 for Windows.
I1 0 0 1m
D1 0 0 D
V1 ADJ 0 0
.model D D
.lib (path removed)\standard.dio
.dc I1 2u 2m 100n
.backanno
.end
?


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

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Back to the subject:

I managed to get the critical points resolved. There were precision problems, where the ton got negative or the pulsewidth overshooted. I fine tuned that and it is sufficient to do the filter simulation.
Thanks a lot for helping.

--
Christoph


Am 26.04.2025 um 17:11 schrieb Christoph Kukulies <kuku@...>:

?thanks :thumb up: , I understand.?

But the representation has changed during the course of me changing the account emails/aliases.

--
Christoph

Am 26.04.2025 um 17:07 schrieb Andy I via <AI.egrps+io@...>:

On Sat, Apr 26, 2025 at 10:13 AM, Christoph wrote:
formerly I was kuku@...
interimly ?kuku@...
Just an FYI - that last one is not the email address you used, and not the one you are subscribed with.? That is the way sends out messages to members.? It needs to convert their email addresses to that form, with "@ " on the end, and the equals sign in the middle.? It has something to do with conforming to new international regulations.
?
Andy
?
_


Re: Diode TVS like zener in LTspice??

 

On Sat, Apr 26, 2025 at 01:14 AM, Александр Бордодынов wrote:
Andy,
you're not quite right. Here is my clarification:
.model SMBJ24CA D(Ron=.65 Roff=50Meg Vfwd=25 epsilon=6 Vrev=25 revepsilon=6 Vpk=24 mfg=Littlefuse type=TVS)
.model SMCJ33A D(Ron=.4 Roff=8Meg Vfwd=.7 epsilon=100m Vrev=38.65 Vpk=33 revepsilon=4 mfg=Littlefuse type=TVS)
A-ha.? Yes, that's true? You used the special "conduction region-wise linear model" which is very different from the regular diode model which is based on the universal Shockley Ideal Diode equation.? The special version you used is essentially a piecewise-linear approximation of the three regions of diode conduction, and makes (almost) no attempt to model the curvature of real diode I/V curves.? I think it might be unique to LTspice.? Whereas the standard Shockley model is in every SPICE program.
?
In some cases, this alternate model is good enough.? It is described as a "computationally light weight representation of an idealized diode", meaning that it trades-off accuracy for simulation speed.
?
As you noted, it is capable of modeling both forward and reverse breakdown at similar (arbitrarily large) voltages.? It can model non-physical diodes.
?
Andy
?


Re: Sine modulated PWM voltage source (PWL file=xxx)

 
Edited

On Sat, Apr 26, 2025 at 10:13 AM, Christoph wrote:
formerly I was <redacted>
interimly??<redacted>
now?<redacted>
Just an FYI - that last one is not the email address you used, and not the one you are subscribed with.? That is the way Groups.io sends out messages to members.? It needs to convert their email addresses to that form, with "@ groups.io" on the end, and the equals sign in the middle.? It has something to do with conforming to new international regulations.
?
Andy
?


Locked Re: Test - please ignore

 

On Sat, Apr 26, 2025 at 10:04 AM, Christoph wrote:
The one from my university account bounced, saying I'm not subscribed with that (physics) address. This one goes through?
Christoph,
?
I am not seeing any evidence that you either added an Email Alias for yourself, or that you subscribed (separately) from your University email address.
?
But I do see a photo in your profile.
?
I might have missed something, but it looks like things did not work the way you thought.? Let's discuss.? I will contact you offline (separately from the group).
?
Andy
?
?


Locked Test - please ignore

 

The one from my university account bounced, saying I'm not subscribed with that (physics) address. This one goes through?
--
Christoph


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

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This is a test, whether both of my emails now work. Please ignore

--
Christoph


Am 25.04.2025 um 18:39 schrieb Andy I via <AI.egrps+io@...>:

Christoph,
?
Off-topic:
?
By the way, you can register your other email address that you used earlier today that bounced.? Then you can send messages to this group from your university address and they won't bounce.? It is known as an "Email Alias" for purposes of these groups.
?
To do that, go to the LTspice group webpage, then click your name in the upper right corner and choose "Settings".? Or go directly to .??Then scroll down to "Advanced Settings for Email Aliases" and click there.? Then type your alternate email address into the box above the "Add Email Alias" button, and then click that button.
?
Adding an Email Alias tells the [LTspice] group server to accept emails send from your Alias address as if it was sent from the address you normally use for this group, and it won't bounce.
?
From Groups Help:
If the email provider you use for your account sends your outgoing messages from an address that is different from your account address, or if you want to be able to send messages to groups from an additional address (for example, a work address) that is different from your account address, you can add an email?alias?to your account:
?
Andy
?


Re: integrate components from Texas Instruments

 

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On 26/04/2025 13:31, patrick.kasten22 via groups.io wrote:
I uploaded the library file under 'files'; I'm still not quite familiar with the forum here. The IC in question is the LMR51635XF. But in general, I have trouble properly integrating ICs, especially from Texas Instruments.
BTW, it's best to send a separate message if you upload something to Files > Temp. Most people do not see the automatically generated message if you check the "Notify Members" box. If you? know how to do it, it's also helpful to include a link to the uploaded file in that message.

--
Regards,
Tony


Re: integrate components from Texas Instruments

 

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On 26/04/2025 13:31, patrick.kasten22 via groups.io wrote:
I uploaded the library file under 'files'; I'm still not quite familiar with the forum here. The IC in question is the LMR51635XF. But in general, I have trouble properly integrating ICs, especially from Texas Instruments.
You cannot use this model file with LTspice. It is encrypted and will only work with PSpice. Similarly, if you? encrypt a model with LTspice, that cannot be used with any other simulator.

I didn't check, but I suspect all 5 of the models TI lists on the LMR51635** product page are encrypted. Looks like you're out of luck.

Similarly, I didn't check whether ADI/LT offered a similar product with a model that would work LTspice.

--
Regards,
Tony


Re: integrate components from Texas Instruments

 

I uploaded the library file under 'files'; I'm still not quite familiar with the forum here. The IC in question is the LMR51635XF. But in general, I have trouble properly integrating ICs, especially from Texas Instruments.


Re: integrate components from Texas Instruments

 

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On 26/04/2025 12:32, patrick.kasten22 via groups.io wrote:
Hi, I'm new to the group and also still a beginner with LTspice. I'm currently using LTspice 24.0.12 — should I rather download the newer version?
My actual problem is that I want to integrate components from Texas Instruments. I followed this video: .
One thing that's different for me: when I click "Create a Symbol," I have to manually save it. I've always saved it in the lib/sym folder. Otherwise, I’m doing everything the same.
It sometimes works with simple components, but with ICs I often get error codes.
Is there a new method for this?
It would be simpler if you just said which component you're trying to make a symbol for. You're getting errors? What errors? We usually don't advise trying to follow Youtube videos, because they're often wrong, and the advice often poor. The first place to look is LTspice's Help manual. It's not an easy read, but contains most of what you need to know.

Anyhow...

There's basically a choice of two ways you can make a symbol for a model that you have.
  1. Draw the symbol outline manually. Add the pins. Save the symbol.
  2. Use LTspice to "Autogenerate" a symbol.
It sounds like you're using the first method. That's good, because at you have control over what the symbol looks like. For method (2), LTspice simply generates a rectangular symbol with the and arbitrary pin layout. It also automatically saves it in the \lib\sym\AutoGenerated folder. Unfortunately, it also hard-codes the ModelFile attribute to that folder on your computer, so nobody else can use it unless you (or they) edit the symbol.

You can, of course, combine the methods: let LTspice autogenerate the symbol, but then you can manually edit the symbol and move the pins where they makes sense, or to match the package, or whatever other criterion you choose. Then, you can re-save the edited symbol (manually) wherever it makes sense, which can be in the same folder as the schematic? schematic that uses it, together with the model. But you could save it anywhere you choose, but preferably not in the same place as LTspice's own symbols. It is suggested to define a separate folder where you keep your own symbols. You can tell LTspice where that is in Control Panel > Search Paths.

The main issue with making your own symbol is getting the pin order correct. Then it appears to simulate, but gives the wrong answers. Another common error, is having a mismatch between the number of pins in the symbol and the number defined in the model.

--
Regards,
Tony


Re: integrate components from Texas Instruments

 

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I strongly advise against YouTube videos. Instead, follow the instructions in the LTspice Help 'Third-party models'. Do not add anything to LTspice native files, because that makes your copy unique and will complicate sharing files. You do not need to create symbols if an existing symbol is usable. You do not need to update to the latest version of LTspice, but you can.

If you get error codes after following the above advice, please tell us exactly what they are.

On 2025-04-26 11:32, patrick.kasten22 via groups.io wrote:
Hi, I'm new to the group and also still a beginner with LTspice. I'm currently using LTspice 24.0.12 — should I rather download the newer version?
My actual problem is that I want to integrate components from Texas Instruments. I followed this video: .
One thing that's different for me: when I click "Create a Symbol," I have to manually save it. I've always saved it in the lib/sym folder. Otherwise, I’m doing everything the same.
It sometimes works with simple components, but with ICs I often get error codes.
Is there a new method for this?
Thanks a lot!
--
Best wishes John Woodgate RAYLEIGH Essex 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

Virus-free.


integrate components from Texas Instruments

 

Hi, I'm new to the group and also still a beginner with LTspice. I'm currently using LTspice 24.0.12 — should I rather download the newer version?
My actual problem is that I want to integrate components from Texas Instruments. I followed this video: .
One thing that's different for me: when I click "Create a Symbol," I have to manually save it. I've always saved it in the lib/sym folder. Otherwise, I’m doing everything the same.
It sometimes works with simple components, but with ICs I often get error codes.
Is there a new method for this?
Thanks a lot!


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

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Thanks, Dennis, for pointing that out. At the moment I'm trying to get the points row defined by fixed time points with relative steps between each new pulse.
It is allowed to change between absolute and relative timepoints, right? Is the unit "u" or "us" in the format of the time values?

It seems that the error occurs after 64 steps:

0.00423177 is not before 0.00423177

I uploaded the project file and a little explanation. Thanks.

--
Christoph

Am 25.04.2025 um 16:31 schrieb Dennis <dennisc@...>:

On Fri, Apr 25, 2025 at 07:49 AM, Christoph wrote:
I'm assuming that the file format is ...
The file format is described in the LTspice help (Help->LTspice Help or F1) under Circuit Elements -> Voltage Source in the section Arbitrary Piece-Wise Linear Voltage Source.
?
There is no structure to the sequence of datapoints. Each point defines the voltage at a point in time. LTspice connects these points with straight lines from the previous point. The PWL source has no knowledge of Trise, Ton, Tfall, or Toff. It's just a sequence of (time, voltage) pairs.?
?
The FILE=<filename> format just allows the (time, voltage) pairs to be read in from a file rather than included directly on the spice line that defines the voltage source.
?
There are a few features which allow easier definition of the time points, most importantly, a "+" before the time value defines a relative time, the given value is the difference between the new time point and the previous time point. There is also an option for a TIME_SCALE_FACTOR parameter on the PWL source which could be set to 1u to define all your times in microseconds rather than seconds, so you don't? need the "u" multiplier on each time point value.??
?
As others have said, if you want to define pulsed waveforms you should perhaps look at the section Time-Dependent Pulsed Voltage Source earlier in the same help page.
?
?


Re: Diode TVS like zener in LTspice??

 

Andy,
you're not quite right. Here is my clarification:
.model SMBJ24CA D(Ron=.65 Roff=50Meg Vfwd=25 epsilon=6 Vrev=25 revepsilon=6 Vpk=24 mfg=Littlefuse type=TVS)
.model SMCJ33A D(Ron=.4 Roff=8Meg Vfwd=.7 epsilon=100m Vrev=38.65 Vpk=33 revepsilon=4 mfg=Littlefuse type=TVS)


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

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Thanks, Andy.
I‘m after it.
Probably my formula is producing this wrong input.
And what my confusion about the file syntax is concerned, I‘m on track again . I was totally besides the rails :)
It‘s indeed pointwise drawing the curve.
I was drawing one pulsetrain per line:

tr/tf=trise/tfall
Starting time 0V
time+tr high 5V
time+tr+ton 5V
time+tr+ton+tf 0V

Still gotta find the error in the generator.
Christoph?



Am 25.04.2025 um 13:34 schrieb Andy I via groups.io <AI.egrps+io@...>:

?
Christoph,
?
In the first of the two files you uploaded (kuku_pwm_pulses.txt.zip), you have some data points that are not sequential.? The very first line is this:
0.000us 0 +0.010us 5 +0.000us 5 +0.010us 0?
which has a point at 0.000 us, then one at 0.010 us, then another at 0.010 us, and one at 0.020 us.? The second and third points are a problem because they are both at the same moment in time, not incrementally increasing.? Fortunately they both have the same voltage or current value (5 V or 5 Amps), but it is fundamentally in error for duplicating a time point.
?
That might be the cause of an error.? Hard to say for sure.
?
But later in the file, I see lines such as these:
8398.438us 0 +0.010us 5 +-1.598us 5 +0.010us 0?
8463.542us 0 +0.010us 5 +-3.195us 5 +0.010us 0?
and those are surely wrong.? ?The time increments are negative, coming before the previous time points.? Those need to be fixed.? (They are also confusing to read, so there is that too.)
?
Andy
?
?


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

Christoph,
?
Off-topic:
?
By the way, you can register your other email address that you used earlier today that bounced.? Then you can send messages to this group from your university address and they won't bounce.? It is known as an "Email Alias" for purposes of these groups.
?
To do that, go to the LTspice group webpage, then click your name in the upper right corner and choose "Settings".? Or go directly to .??Then scroll down to "Advanced Settings for Email Aliases" and click there.? Then type your alternate email address into the box above the "Add Email Alias" button, and then click that button.
?
Adding an Email Alias tells the [LTspice] group server to accept emails send from your Alias address as if it was sent from the address you normally use for this group, and it won't bounce.
?
From Groups Help:
If the email provider you use for your Groups.io account sends your outgoing messages from an address that is different from your account address, or if you want to be able to send messages to groups from an additional address (for example, a work address) that is different from your account address, you can add an email?alias?to your account:
?
Andy
?


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

On Fri, Apr 25, 2025 at 09:59 AM, Christoph wrote:
could it be that I'm assuming a different file format as I posted in the other email:
File format?? No.? The file formal for a PWL file is ordinary text.
?
Data format?? Possibly.
?
PWL data is always pairs of numbers, where the first number of the pair is time, and the second number is the voltage or current.? This is very well documented and every SPICE since the beginning of time uses the same format.

Syntax: Vxxx n+ n- PWL(t1 v1 t2 v2 t3 v3...)

Note that "t1 v1" is the first pair, "t2 v2" is the second pair, and so on.
?
PWL means "piece-wise linear".? The data points describe a set of points, and then LTspice "connects the dots" between the points, giving you a piece-wise linear waveform.
?
Timepoint ??????????????????????????V0 Trise. ??Von Ton ?????????????????????????????????????V? ?Tfall ??????Toff
0.000000000000000000us 0 ?0.010us 5 ???32.552083333333335702us 5 ??0.010us 0
I don't know where you got that from, but it definitely does not describe PWL.? That is similar to the description of a SPICE "PULSE" source, not PWL.? But it is incorrect for PULSE too.? I think it is not any SPICE syntax.
?

Some (undocumented) data formatting?
PWL is not "undocumented".? What you used above is undocumented, and incorrect, and definitely will not work for a PWL file.
?
Andy
?


Re: Sine modulated PWM voltage source (PWL file=xxx)

 

On Fri, Apr 25, 2025 at 07:49 AM, Christoph wrote:
I'm assuming that the file format is ...
The file format is described in the LTspice help (Help->LTspice Help or F1) under Circuit Elements -> Voltage Source in the section Arbitrary Piece-Wise Linear Voltage Source.
?
There is no structure to the sequence of datapoints. Each point defines the voltage at a point in time. LTspice connects these points with straight lines from the previous point. The PWL source has no knowledge of Trise, Ton, Tfall, or Toff. It's just a sequence of (time, voltage) pairs.?
?
The FILE=<filename> format just allows the (time, voltage) pairs to be read in from a file rather than included directly on the spice line that defines the voltage source.
?
There are a few features which allow easier definition of the time points, most importantly, a "+" before the time value defines a relative time, the given value is the difference between the new time point and the previous time point. There is also an option for a TIME_SCALE_FACTOR parameter on the PWL source which could be set to 1u to define all your times in microseconds rather than seconds, so you don't? need the "u" multiplier on each time point value.??
?
As others have said, if you want to define pulsed waveforms you should perhaps look at the section Time-Dependent Pulsed Voltage Source earlier in the same help page.
?
?