LTSpice Slow: help, please.

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A fourth trick is to randomly change a few parameters by a very small amount, for example reducing the supply voltage by a few millivolts. I know that sometimes worked for PSpice 20 years ago.

I sometimes change some resistor value that is set at say 1k to 999 ohms, and that gets LTspice to run again. Irrelevant to the circuit of course, and I have no idea why, but it often bails me out.

Jan
 
Do you also get error messages about non-convergence or only gmin stepping failed?
Only gmin, no error, no warning apart in the spice error log.
If not, you will have to do your homework, and add realistic imperfections to otherwise idealistic components, mainly the reactive ones, use another solver, change the options, etc.
:-(
The Yahoo LTspice group offers a lot of help for this type of problem, and if you cannot find an answer, you can always post your question (but without disclosing your circuit, it will be difficult).
By example, why they do not provide a constantly improved centralized complete list of best models that everybody could share?
I don't understand the way this Yahoo group is working. A community group around a proprietary Program ? Like a fan club ?
I was very surprised, the first time I opened this Soft, to see there was not a square wave and triangle waves generator as a default component. (So easy to program !). Why, in a bloc of directives, the interface was not able to read , greyed, the commented(;) ones, offering with a simple click to swap between the various analysis (trans, AC etc.) without to have to manually change the texts. Why the OLG measurement were not provided by default as components and the margin values reported in spice error log etc. (long list of requests ;-).
The takeover of LT by AD was clearly bad news for LTspice: the AD management doesn't want to kill LTspice immediately, because of the fame and success, but the strategy seems to be a slow suffocation, that will lead to a progressive abandonment of the software
A M$$$ or ADOBE* like politic: to buy a software with the intention to kill some concurrency ? I don't see the interest, here. The idea behind LTSpice, if i understand well, was to offer for free a proprietary program that promotes (defauts models) their products. It allows others models, but with an added complexity. The XVII version do not give a good image of ADI !

*See what's happened to Fireworks ;-(
 
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The user inteface of LTspice has always been a bit rough and primitive, but at least it didn't bug or require manual editing of the simulation directives in the IV version.

It was light and agile, required minimal resources and adapted itself to the system it ran on, and the jump into XVII was clearly a regression on many fronts.

As for the Yahoo group, it is a remnant of the old, pre-2000 internet era (think of geocities, POTS modems, etc.)

I don't think the group was sponsored by LT, although it certainly receives help and privileged information from them
 
If you don't like the software, ask for your money back.

People find a lot of problem with Microchip Harmony too.
Yet another free software package.

Some of these packages are massive pieces of software so not surprising there is the odd bug.
I have been writing my own software pcbcad51 since 1990 and I still find a rare bug. Its over 500,000 lines of code so the odd bug might be expected.
 
BTW: Everything is money based, in your way to see the life ?
Neither LT nor ADI is in a charity, DIY or open-source business: they try to promote their products by showcasing their expertise, being user-friendly (up to a point), but there are limits, and you have reached them very quickly.

You can try commercial offerings (but you will probably be disappointed, even if it costs you dear) or free open-source alternatives (I do not know of any, but they probably exist), and you will probably be disappointed as well.

In our world, nothing is actually free or or perfect, and you have to live with tradeoffs.
 
I have been writing my own software pcbcad51 since 1990 and I still find a rare bug. Its over 500,000 lines of code so the odd bug might be expected.
It is where open source and community development had a huge advantage. Lot of beta testers, lot of developers. Love and dedication for the project.
Linux has always being lot less buggy than Windows (before XP).
 
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I was very surprised, the first time I opened this Soft, to see there was not a square wave and triangle waves generator as a default component. (So easy to program !).
-(
Creating a square wave in LTSpice is a trivia, so easy to setup for anybody who is ready to read the handbook. You wish to pop up this program for pre-fabricated readly clickable blocks - that are totally redundant. You may call this user friendly - I call such programme bulky bloatware.
 
Creating a square wave in LTSpice is a trivia, so easy to setup for anybody who is ready to read the handbook. You wish to pop up this program for pre-fabricated readly clickable blocks - that are totally redundant. You may call this user friendly - I call such programme bulky bloatware.
Strange comment. We have pulse, sin, exp etc. Why not square for input generator etc, like in real life ? Makes the schematic clean, swap in a click, keeping the voltage value and .... no need for handbook.
 
Strange comment. We have pulse, sin, exp etc. Why not square for input generator etc, like in real life ? Makes the schematic clean, swap in a click, keeping the voltage value and .... no need for handbook.

As far as I know, SPICE "pulse" sources generate square waves when you just specify a rise time, fall time, pulse width and period. Make the rise and fall times equal to half the period and the pulse width zero and you have a triangle.
 
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Even if there was a separate square wave source, you still would have to input frequency or period, pulse width or duty cycle, rise and fall times. Same as with the 'pulse' source.
Both would be equivalent in terms of inputs required, and they could have named the 'pulse' source 'square wave' with no other changes and the same functionality.
So I don't see any advantage to what effectively is duplicating something that is already there, except maybe for personal preference. A small disadvantage could be that it would be one more item to learn or forget how to use and the need to look it up.

Jan
 
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