Re: Periodic signal from PWL file
There seems to be a subtle
difference:
A list of data points or a
file reference can be repeated a fixed amount of times
<n>, or forever
PWL REPEAT FOR <n> (|<file spec>)
ENDREPEAT??????? * 'file spec' has | character
PWL REPEAT FOREVER (|<file spec>) ENDREPEAT
E.g. to repeat a sequence of values for five times
PWL REPEAT FOR 5 ( 0 1 1 1 2 2 3 1 ) ENDREPEAT
PWL REPEAT FOR 5 ( file=<name of file> )
ENDREPEAT????? * 'file=<name
of file> does not have | character
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 16:56, Christoph wrote:
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Show quoted text
Fine so far, but using the | (vertical bar) gives an error.
PWL REPEAT FOREVER
(file=Z:\Users\kuku\Documents\LTspiceXVII\pulses.txt) ENDREPEAT
works, while
PWL REPEAT FOREVER (|
file=Z:\Users\kuku\Documents\LTspiceXVII\pulses.txt) ENDREPEAT
doesn’t So what is the purpose of the ?|‘?
—
Christoph
Am 08.07.2023 um 17:52 schrieb John Woodgate
< jmw@...>:
If you look at the other examples on
that page, you will see that the | character is
only used with a file, not with a sequence of
numbers.
======================================================================================
Best wishes John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget. I see, and I remember. I do, and
I understand. Xunzi (340 - 245 BC)
On 2023-07-08 16:40,
Christoph wrote:
Thanks. This worked. Though the ?|‘ symbol (pipe) is
confusing. If it designates that the data is supposed
to be piped from the file, it doesn’t work. OTOH,
should it mean an ?or“, then the empty left side of
the ?|‘ shouldn’t be empty but contain a
list of <time><value> pairs.
—
Christoph
Am 08.07.2023 um 15:11 schrieb
John Woodgate < jmw@...>:
There is an
undocumented REPEAT feature in the
Wiki at: /g/LTspice/wiki/13810
A
list of data points or a file
reference can be repeated a fixed
amount of times <n>, or
forever
PWL REPEAT FOR
<n> (|<file spec>)
ENDREPEAT
PWL REPEAT FOREVER
(|<file spec>) ENDREPEAT
======================================================================================
Best wishes John Woodgate OOO-Own Opinions
Only
Rayleigh, Essex UK
I hear, and I forget. I see, and I
remember. I do, and I understand. Xunzi
(340 - 245 BC)
On 2023-07-08
13:51, Christoph wrote:
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
|
Re: Periodic signal from PWL file
Fine so far, but using the | (vertical bar) gives an error.
PWL REPEAT FOREVER (file=Z:\Users\kuku\Documents\LTspiceXVII\pulses.txt) ENDREPEAT works, while PWL REPEAT FOREVER (| file=Z:\Users\kuku\Documents\LTspiceXVII\pulses.txt) ENDREPEAT
doesn’t So what is the purpose of the ?|‘?
— Christoph
toggle quoted message
Show quoted text
Am 08.07.2023 um 17:52 schrieb John Woodgate < jmw@...>:
If you look at the other
examples on that page, you will see that the | character is
only used with a file, not with a sequence of numbers.
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 16:40, Christoph wrote:
Thanks. This worked. Though the ?|‘ symbol (pipe) is confusing. If
it designates that the data is supposed to be piped from the file,
it doesn’t work. OTOH, should it mean an ?or“, then the empty left
side of the ?|‘ shouldn’t be empty but contain a
list of <time><value> pairs.
—
Christoph
Am 08.07.2023 um 15:11 schrieb John Woodgate
< jmw@...>:
There is an undocumented REPEAT
feature in the Wiki at: /g/LTspice/wiki/13810 A list of data points or
a file reference can be repeated a fixed amount
of times <n>, or forever
PWL REPEAT FOR <n>
(|<file spec>) ENDREPEAT
PWL REPEAT FOREVER (|<file
spec>) ENDREPEAT
======================================================================================
Best wishes John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget. I see, and I remember. I do, and
I understand. Xunzi (340 - 245 BC)
On 2023-07-08 13:51,
Christoph wrote:
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
_._,_._,_
|
Re: Discrete data points in plot view
I think you have to export the
data to Excel or similar to plot in those ways.
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 16:52, Christoph wrote:
toggle quoted message
Show quoted text
My array of PWL data (time value pairs) appears points (that optionally can be made visible) and being connected by line pieces.
Since these are discrete sample points I’d rather see them as points only or as a pulse train of vertical lines of height corresponding to the amplitude. Is this possible?
—
Christoph
|
Re: Warning: Multiple definitions of model ...
Hello Andy,
Thanks for the detailed words.
I know that the faulty libraries only cause warnings but no errors. But sometimes I do simulations, and the results are checked by other people. And that's where warnings don't look good.
In my standard.bjt file I deleted the five obviously faulty models and the warnings disappeared.
This will probably only remain until the next LTspice update. Hence my question as to whether the incorrect entries can be avoided in the future.
Even if I use components from ADI, there are almost always additional transistors in the circuit. I'm surprised that ADI ignores errors and warnings. I wasn't used to that from LTC.
I'm also registered in the QSPICE group, but haven't had time to deal with QSPICE in more detail so far. (Never change a …)
Bernhard
|
Re: Periodic signal from PWL file
If you look at the other
examples on that page, you will see that the | character is
only used with a file, not with a sequence of numbers.
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 16:40, Christoph wrote:
toggle quoted message
Show quoted text
Thanks. This worked. Though the ?|‘ symbol (pipe) is confusing. If
it designates that the data is supposed to be piped from the file,
it doesn’t work. OTOH, should it mean an ?or“, then the empty left
side of the ?|‘ shouldn’t be empty but contain a
list of <time><value> pairs.
—
Christoph
Am 08.07.2023 um 15:11 schrieb John Woodgate
< jmw@...>:
There is an undocumented REPEAT
feature in the Wiki at: /g/LTspice/wiki/13810
A list of data points or
a file reference can be repeated a fixed amount
of times <n>, or forever
PWL REPEAT FOR <n>
(|<file spec>) ENDREPEAT
PWL REPEAT FOREVER (|<file
spec>) ENDREPEAT
======================================================================================
Best wishes John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget. I see, and I remember. I do, and
I understand. Xunzi (340 - 245 BC)
On 2023-07-08 13:51,
Christoph wrote:
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
|
Discrete data points in plot view
My array of PWL data (time value pairs) appears points (that optionally can be made visible) and being connected by line pieces.
Since these are discrete sample points I’d rather see them as points only or as a pulse train of vertical lines of height corresponding to the amplitude. Is this possible?
—
Christoph
|
Re: Periodic signal from PWL file
Thanks. This worked. Though the ?|‘ symbol (pipe) is confusing. If it designates that the data is supposed to be piped from the file, it doesn’t work. OTOH, should it mean an ?or“, then the empty left side of the ?|‘ shouldn’t be empty but contain a list of <time><value> pairs.
— Christoph
toggle quoted message
Show quoted text
Am 08.07.2023 um 15:11 schrieb John Woodgate < jmw@...>:
There is an undocumented REPEAT
feature in the Wiki at: /g/LTspice/wiki/13810 A list of data points or a
file reference can be repeated a fixed amount of times
<n>, or forever
PWL REPEAT FOR <n> (|<file spec>) ENDREPEAT
PWL REPEAT FOREVER (|<file spec>) ENDREPEAT
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 13:51, Christoph wrote:
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
|
Re: Warning: Multiple definitions of model ...
Mike Fraser wrote, "I can only hope that someone at Analog Devices will spend time and clean up this mess."
All of us wished that Analog Devices would do that.
But they are too inept to do that.
Andy
|
Re: Warning: Multiple definitions of model ...
Bernhard,
Those Warning messages about "Multiple definitions" of those four BJTs can be ignored.??The good news is that they are only Warnings.? And in your case, they do not affect your simulation, not one bit.??They have been there for years.? Your schematic did not cause them.
[Rant mode on.]
They got there because someone at Analog Devices put them there.
They are still there because Analog Devices is too inept to fix it.
Everyone who downloads LTspice gets a bad "standard.bjt" file.??(You get a bad "standard.jft" file too, but that'a for a different reason, and the mistakes in that one are very real and very bad, but that one is not entirely Analog Devices's fault and we won't get into that now.? It's been discussed already, separately.)? The "standard.bjt" file has duplicate entries for the 2scr375p, bc847b, bc847c, and bc857b.? LTspice gives you a warning whenever it sees duplicate definitions of any .MODEL statements, whether or not the model parameters actually differ.
Because your schematic has even one BJT on it, LTspice loads "standard.bjt" into your simulation, and bang, you get those warnings.
Like I said, you can safely ignore them.
I thought that if you update your models in LTspice, it might "fix" those duplicate definitions, and the warnings might go away.? Or maybe not.? The thousands of people who download LTspice daily are all being handed a bad copy of "standard.bjt" with these four mistakes in it -- and Analog Devices is too stupid to fix it.? Yes, they have been told about it.? But they do nothing about it.
Mike Engelhardt used to manage LTspice.? If he were still doing it, this problem would have been fixed years ago, and probably would not have happened in the first place.? But alas, he is no longer managing LTspice at Analog Devices.? Instead, we have other people including German Ergueta who are not up to Mike's standards, and appear to have no concept of library consistency.? Mr. Ergueta gave me a really lame sob-story about how long it takes to verify models, and garbage like that.? He totally misses the point.? To fix these four Warnings, all it would take is about 30 seconds with a text editor to remove the duplicates.? Done.? But Analog Devices is too lame to do a simple fix like that.
The good news is that you can ignore these Warning messages.? Unless you use one of those four transistor models, it won't affect you, not one bit.? Even if you did use one of those four transistors, you can relax because you are getting a real model, even if LTspice has a second model for the same transistor.? So it is not really a problem.? And anyway a Warning is just a Warning, it's not an Error.
The bad news is that Analog Devices seems to have no interest whatsoever in fixing their model libraries.? Until people like Mr. Ergueta and the other employees of Analog Devices who have a say in how LTspice works -- until they WAKE UP and fix simple problems like this instead of continuing to propagate it, it's going to be there forever.
Don't hold your breath.? Mr. Ergueta doesn't care that you have bad models, that could have and should have been fixed ages ago.
By the way, maybe you should take a look at QSPICE.? I recommend it as a replacement for the mistakes that Analog Devices seems to be unable or unwilling to fix.
[Rant mode off.]
FYI, you could eliminate those Warnings yourself by editing your "standard.bjt" and renaming the duplicate model names.? It's a plain text file and can be edited with a good text editor, including LTspice itself.
Andy
|
Re: Warning: Multiple definitions of model ...
For BC847C Rohm offers the SPICE parameter set of BC547B. Therefore the current gain of the BC847C model is too low.
In the LTspice standard.bjt there are BC847B and BC847BT116, both from Rohm and with identical parameters (bloated file, T116 is only a delivery package).
Or look at the selection parameters for 2SCR542F3.
While its SPICE parameters are identical to 2SCR542P.
I agree with Tony, the standard libraries are indeed a mess.
I mostly use my own models. But the warnings caused by LTspice's own files that appear anyway, bother me.
Bernhard
|
Re: Periodic signal from PWL file
There is an undocumented REPEAT
feature in the Wiki at: /g/LTspice/wiki/13810
A list of data points or a
file reference can be repeated a fixed amount of times
<n>, or forever
PWL REPEAT FOR <n> (|<file spec>) ENDREPEAT
PWL REPEAT FOREVER (|<file spec>) ENDREPEAT
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 13:51, Christoph wrote:
toggle quoted message
Show quoted text
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
|
Re: Periodic signal from PWL file
On 08/07/2023 14:51, Christoph wrote:
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
Yes you can. Here is an example:
PWL repeat forever (0 0 0.5 1 1.5 -1 2 0)
endrepeat
You can use the same syntax with a PWL file, too.
--
Regards,
Tony
|
Periodic signal from PWL file
I have created a pulse source from a PWL file.
It‘s 32 samples of a signal.
Is it possible to make this pulse train periodic?
Or do I have to provide the pulse samples for every period by the PWL file?
—
Christoph
|
Re: Warning: Multiple definitions of model ...
On 08/07/2023 14:18, Mike Fraser wrote:
I have the latest
update to LTspice 17.1.9.
In my opinion, the transistor listing has reached a point where it
canot be trusted.
? ? ? ? ? Anyone using the built in BJT listing needs to double or
triple check any selected model.
I opened a schematic and placed 2 NPN devices.
I then tried to select the BC847C as my choice.
LTspice lists 2 models for this device.
The NXP mfg. listing shows a rating of 45V and 100 mA.
The ROHM mfg. listing shows a rating of 32V and 200 mA.
When you try to select the ROHM model for your BJT, LTspice
automatically selects the NXP model.
Also, the spice model for the ROHM part is nothing more than
completely worthless garbage.
The real model can be found here :
Additionally, the ROHM data sheet specifies 45V and 100 mA
ratings.
I can only hope that someone at Analog Devices will spend time and
clean up this mess.
You can hope, but don't hold your breath. The standard libraries
have been a mess for quite a while. I offered my help, but it wasn't
accepted.
--
Regards,
Tony
|
Re: Warning: Multiple definitions of model ...
I have the latest update to LTspice 17.1.9.
In my opinion, the transistor listing has reached a point where it canot be trusted.
? ? ? ? ? Anyone using the built in BJT listing needs to double or triple check any selected model.
I opened a schematic and placed 2 NPN devices.
I then tried to select the BC847C as my choice.
LTspice lists 2 models for this device.
The NXP mfg. listing shows a rating of 45V and 100 mA.
The ROHM mfg. listing shows a rating of 32V and 200 mA.
When you try to select the ROHM model for your BJT, LTspice automatically selects the NXP model.
Also, the spice model for the ROHM part is nothing more than completely worthless garbage.
The real model can be found here :
Additionally, the ROHM data sheet specifies 45V and 100 mA ratings.
I can only hope that someone at Analog Devices will spend time and clean up this mess.
Mike
|
Re: Warning: Multiple definitions of model ...
The deleted devices are in my
Netlist, not the Error Log.
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 10:31, Bernhard Weiskopf
wrote:
toggle quoted message
Show quoted text
Interesting.
I have just tested with "NPN" and "D" but none of them are replaced acc. to the "SPICE Error Log" file (Ctrl+L).
But the multiple definitions of bjt models is still present.
My test file AF_Amp1.asc is in the Temp folder.
Bernhard
|
Re: Warning: Multiple definitions of model ...
Interesting.
I have just tested with "NPN" and "D" but none of them are replaced acc. to the "SPICE Error Log" file (Ctrl+L).
But the multiple definitions of bjt models is still present.
My test file AF_Amp1.asc is in the Temp folder.
Bernhard
|
Re: Warning: Multiple definitions of model ...
I was just about to post
another example of this. In addition, I find in the netlist
generic devices NPN, PNP and D, which were in the .ASC but
have been replaced by real devices, BC547B, BC557B and 1N4148.
======================================================================================
Best wishes
John Woodgate OOO-Own Opinions Only
Rayleigh, Essex UK
I hear, and I forget.
I see, and I remember.
I do, and I understand.
Xunzi (340 - 245 BC)
On 2023-07-08 09:40, Bernhard Weiskopf
wrote:
toggle quoted message
Show quoted text
Since several weeks the "SPICE Error Log" file contains these lines even when these transistors are not used:
Warning: Multiple definitions of model "2scr375p" Type: BJT
Warning: Multiple definitions of model "bc857b" Type: BJT
Warning: Multiple definitions of model "bc847c" Type: BJT
Warning: Multiple definitions of model "bc847b" Type: BJT
The multiple definitions are in c:\Users\...\AppData\Local\LTspice\lib\cmp\standard.bjt
E.g.
2SCR375P: Rohm, twice with identical parameters
BC847C: Duplicate from Rohm with wrong parameters, e.g. IKF=1.3 Vceo=32, Icrating=200m, base collector and base emitter capacities interchanged …
I am using LTspice version 17.1.9 and did never edit this model parameter file.
Does anyone know how the duplicates got in and how to avoid duplicates in the future?
Bernhard
|
Warning: Multiple definitions of model ...
Since several weeks the "SPICE Error Log" file contains these lines even when these transistors are not used:
Warning: Multiple definitions of model "2scr375p" Type: BJT
Warning: Multiple definitions of model "bc857b" Type: BJT
Warning: Multiple definitions of model "bc847c" Type: BJT
Warning: Multiple definitions of model "bc847b" Type: BJT
The multiple definitions are in c:\Users\...\AppData\Local\LTspice\lib\cmp\standard.bjt
E.g.
2SCR375P: Rohm, twice with identical parameters
BC847C: Duplicate from Rohm with wrong parameters, e.g. IKF=1.3 Vceo=32, Icrating=200m, base collector and base emitter capacities interchanged …
I am using LTspice version 17.1.9 and did never edit this model parameter file.
Does anyone know how the duplicates got in and how to avoid duplicates in the future?
Bernhard
|
Re: I am unable to add and use the BS138 (BSS138) model for simulation Iin LTSpice. can anyone help me with this
I have made a VMOS model based on the Onsemi datasheet, which adheres pretty well to all the graphs. Unfortunately, I can't upload ATM, as our power has been taken out by a big thunderstorm.
-- Regards, Tony
On 7 Jul 2023 19:06, Andy I <AI.egrps+io@...> wrote: Richard wrote, "I just went to diodes.com and found the newest spice model for the?"
And ... what is your point?
That was one of the four BSS138 SPICE models that vedhaanth648 already pointed to, yesterday, when they asked their question.? What do you make of that one particular model, and why should we think it is either better or worse than other BSS138 SPICE models?
I think it's funny that you call this one "the newest spice model" when it is in fact 16 years old.? I found many other BSS138 models which are newer than that one.? So the "newest spice model" you found is definitely not newest!? Check your facts.
But as I said previously, newness does not imply goodness.
Just an FYI -- I have four BSS138 SPICE models from Diodes Inc.? And I've got three more from Onsemi, one from NXP, and six from Infineon.? What makes any model good?? I'd say it is how well it agrees with what the part actually does, which is best determined by purchasing a few dozen samples from various manufacturers, and hooking each one up to some test equipment.
Andy
|
John Woodgate
Christoph
Tony Casey