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Re: Warning: Multiple definitions of model ...
开云体育Some valid points, but I think the proposal is not 'either/or'. I see no objection to putting the expanded files in a new subfolder of Files, as long as it has a warning about how to use it and not use it. Not everyone has Tony's skills
in verifying a model. Some of us need more support. ======================================================================================
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 2023-07-09 22:02, Tony Casey wrote:
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Re: Warning: Multiple definitions of model ...
I'm not against a repository of models - we already have one in the group 's Files section. But I am against trying usurp the standard libraries. Most people coming to this group, at least initially, will have only the installation files. Once people have learnt to deal with 3rd party models, they can use what they want. We have had endless issues over the years with people adding extra models to the standard libraries and then wondering why no one can run their problematic schematics, when they believe they have uploaded everything necessary. Many of us of us are not satisfied with ADI's chaotic recent efforts with the standard libraries, but the solution is not additional chaos. Although this is a big group, it still only represents a fraction of the LTspice user base. We may not like the current situation, but we need to concentrate on enabling people to use LTspice despite the current issues, by freeing them from the initial dependency on the standard libraries. ADI's current preoccupation is making sure that their own example schematics run with what is what is currently in the standard libraries. That is where they see the critical value-added issues. People complaining about multiple BC848s are way down in the noise, because they are probably not buying lots of ADI's premium products. For heaven's sake, even the multiple BC848s issue is trivial compared to the dozens of JFETs in that library that have massively faulty models. If anything, I think emphasis ought to be on educating users to validate whatever models they are using. Quality trumps quantity. What's the value in having 1875 BJT models that have little to zero provenance? Have you validated any of them? German Ergueta is right when he says that validation is a time consuming issue. I'd like to think that's because he has lots of people validating things. He probably does - just not the standard libraries. Could we do a better job? Possibly. But who's going to do the heavy lifting?? And not get paid for doing it. And would it have a global impact? No. Regards, Tony? On 9 Jul 2023 20:21, eewiz <eewiz@...> wrote:
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Re: Warning: Multiple definitions of model ...
开云体育It sounds a very good idea, but
keeping the same filenames could cause untold confusion. Is
there any way of making the names different?? The only thing I
can think of is making them all upper-case, i.e. STANDARD.BJT
etc., which humans see as different but LTspice doesn't. ======================================================================================
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 2023-07-09 19:21, eewiz wrote:
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Re: Warning: Multiple definitions of model ...
开云体育Hello All, Members could maintain a set of the standard.xxx files for use by the group. I've been doing that for many years now. If the group retained a set of maintained files in an easy to reach repository similar to /files/temp, group members could downloaded them when needed to replace the LTspice versions that appear after an LTspice update. I have a set of standard.xxx files that I have maintained across LTspice updates since LTspice IV was all the rage. ?????????????????????? ? ?? # OF DEVICES FILE??????????????? MAINTAINED? LTspice standard.bjt?? ? ? ?? 1875 ?????? ?? 306 standard.dio???????? 2575 ?????? ?? 928 standard.jft ? ?????? 1306??????????? 140 standard.mos????? 1710????????? 1207 The library files could be kept in a single zip that could be easily dropped onto the \cmp directory to clobber the undesirable LTspice official standard.xxx files after an LTspice update. Of course there are no guaranties of model quality from anyone including the author of LTspice but, I much prefer having 1875 BJT models to choose from as opposed to the 306 model provided by AD. The paradigm could then be changed from "missing BJT model, be sure to include your model in your working directory" to "Missing BJT model, be sure to download the set of standard.xxx files from the group." Then group members could leave the substandard standard.xxx files to suffer the rest of the world. If I knew anything about PC programming, I would write something to move the maintained files out of the way, call LTspice into update mode, combine any new devices into the maintained files and finally overwrite the downloaded LTspice files. But, I don't. I write embedded system code in assembler and C, where I get to roll all my own code. I have no idea how to deal with calling a zillion pieces of somebody else's code to piece together a PC program. So I just maintain my own copies of the standard.xxx files that I process in a text editor. Back in the 90's I used to easily accomplished such tasks with dBase/Clipper but that capability disappeared for me when M$ abandoned 16-bit software altogether. All for now
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Re: Warning: Multiple definitions of model ...
开云体育Output is engraved on stone
tablets. ======================================================================================
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 2023-07-09 16:07, cander shelter via
groups.io wrote:
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Re: Warning: Multiple definitions of model ...
There is also? JSPICE"JSPICE is a simulator for superconductor and semiconductor circuits, and is based on the general-purpose circuit simulation program SPICE2; it is incorporated with the Josephson junction model. It supports the same SPICE2 format and is running in the batch mode. Like SPICE2, it has ASCII plotting facility built in.? The simulator is only valid for transient simulations and DC operating point; AC small-signal analyses are not allowed."
On Sunday, July 9, 2023, 6:57:47 PM GMT+4, Christopher Paul <christopherrpaul1@...> wrote:
On Sat, Jul 8, 2023 at 10:15 AM, Andy I wrote: I wonder if it might be worth the while of those of us concerned about Analog Device's inaction in these matters to take to social media to suggest alternatives to LTSpice. With apologies to Arlo Guthrie and his "Alice's Restaurant" and the Wikipedia site I pulled this from, "He predicts that a single person doing it would be rejected as "sick" and that two people doing it, in harmony, would be rejected as??"", but that once three people started doing it they would begin to suspect "an organization" and 50 people a day would be recognized as??a movement." Thoughts? |
Re: Warning: Multiple definitions of model ...
On Sat, Jul 8, 2023 at 10:15 AM, Andy I wrote:
I wonder if it might be worth the while of those of us concerned about Analog Device's inaction in these matters to take to social media to suggest alternatives to LTSpice. With apologies to Arlo Guthrie and his "Alice's Restaurant" and the Wikipedia site I pulled this from, "He predicts that a single person doing it would be rejected as "sick" and that two people doing it, in harmony, would be rejected as??"", but that once three people started doing it they would begin to suspect "an organization" and 50 people a day would be recognized as??a movement." Thoughts? |
Re: PWL sources (was but not related to: "Discrete data points in plot view")
开云体育Dave, Of course he was, although I find it more instructive to show someone how it does work, rather than explaining how or why some other example does not work. All for now
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Re: PWL sources (was but not related to: "Discrete data points in plot view")
开云体育eewiz, I think Bonkers was mixing absolute timing with relative timing notation. If you delete all of the + signs at the beginning of the lines, it makes pretty good sense, as absolute times. ? It took me a long time to get it through my head that relative time notation made the job a lot easier!
? From: [email protected] <[email protected]> On Behalf Of
eewiz
Sent: Saturday, July 08, 2023 6:34 PM To: [email protected] Subject: EXTERNAL: Re: [LTspice] Discrete data points in plot view ? Hello Christoph, ? Bonkers may be leading you down the primrose path. If you follow Bonkers' advice the length of bit[1] will be twice the length of bit[0] and the length of bit[2] will be three times the length of bit[0]. The slew rate will also progress to 2 times and then 3 times longer... ? This is all you need to make a PWL file with relative timing. 0??? 0?????????????? at 0 time its 0 volts. Rinse and Repeat... ? If you would prefer to work with parameters instead of numbers, be my guest. It took me just several minutes to copy and past what I needed in Excel to create a file that's 14,582 lines long. As I made it, I made some changes to add some discontinuities on a periodic basis and then paste, paste, paste some more. My file runs for about 583ms. If I had known of the REPEAT syntax at the time, I could have made use of it but, cut and paste is easy, LTspice syntax is not. ? Bonkers wrote:
All for now |
Re: PWL sources (was but not related to: "Discrete data points in plot view")
开云体育Hello Christoph, Bonkers may be leading you down the primrose path. If you follow Bonkers' advice the length of bit[1] will be twice the length of bit[0] and the length of bit[2] will be three times the length of bit[0]. The slew rate will also progress to 2 times and then 3 times longer... This is all you need to make a PWL file with relative timing. 0??? 0?????????????? at 0 time its 0 volts. +750n??? 10 ??? take 750ns to go from 0V to 10V with a linear slope. +100u??? 10???? stay at 10V for 100us. +1.5u??? -10???? take 1.5us to go from 10V to -10V with a linear slope. +58u??? -10????? stay at -10V for 58us. +1.5u??? 10????? take 1.5us to go from -10V to 10V with a linear slope. +100u??? 10???? stay at 10V for 100us. Rinse and Repeat... If you would prefer to work with parameters instead of numbers, be my guest. It took me just several minutes to copy and past what I needed in Excel to create a file that's 14,582 lines long. As I made it, I made some changes to add some discontinuities on a periodic basis and then paste, paste, paste some more. My file runs for about 583ms. If I had known of the REPEAT syntax at the time, I could have made use of it but, cut and paste is easy, LTspice syntax is not. Bonkers wrote: All for now |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
Kerim, can you simplify your 2-winding transformer model a little?? Having an ideal transformer at its core, I think you can "push" the other elements through it to the other side and combine them.? Then can't you apply it to your 3-winding transformer too?
Andy |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
OT: Obviously, implementing the push-pull topology is much easier than the bridge one. But this has a price: [1] The amplitude of the driving PWM voltage is doubled. It is from Vbat to –Vbat instead of Vbat to 0 or -Vbat to 0 in case of the bridge. [2] The PWM resolution is halved. Its duty cycle is 50% for the zero voltage output, while it is 0% in case of the bridge. [3] The resistance of the low-voltage side (primary?) is doubled (by splitting the primary 1-winding to 2 windings that take the same space). |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
On Sat, Jul 8, 2023 at 11:22 PM, John Woodgate wrote:
Although I added a load, the new 3-winding model needs to act as LPF even without it, as in the case of the 2-winding one. I am afraid that with an open output, any leakage inductance cannot filter out the high frequency. Did you see my humble solution on the subcircuit schematic of my 2-winding transformer, 'SineXF_lk__01_HY_'? |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
On Sat, Jul 8, 2023 at 11:30 PM, Andy I wrote:
Kerim,Andy, You are right in all you said. I was somehow shy to upload what I tried doing because their responses were rather ridiculous :( So, I uploaded the schematic with a conventional 3-winding transformer so that it could be replaced with a practical model and tested. Kerim |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
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Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
Kerim,
But your 3-winding transformer:
If the leakage inductance is responsible for the transformer's low-pass filtering, the 3-winding transformer lacks any.? What did you do to it when tweaking it to act as an LPF?? You did not leave your tweaks on the schematic, right? Andy |
Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
开云体育More: You don't see any LPF
effect because you set K to 1, so there is no leakage
inductance. If you set K to say 0.98 you will see a filtering
effect. ======================================================================================
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 21:22, John Woodgate
wrote:
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Re: Push-Pull 3-Winding Transformer Model Acting as LPF too?
开云体育Present: far too much stuff not relevant to the question of the transformer acting as a low-pass filter. Kerim, if you accept that a
two-winding transformer acts as a low-pass filter, you should
be able to see that the presence of a third winding doesn't
change that.? The leakage inductance and the load resistance
are still there, as for the two-winding transformer. ======================================================================================
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 21:13, Andy I wrote:
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