No, spice always starts a transient simulation from the DC calculated solution, whatever that is.
I did a simulation of a dc servo and the sine wave started on the crest of the sine wave. Thinking about it was after the integrator so maybe it was shifted by 90 degrees. The sine wave generator itself starts from zero.
The sine wave generator starts from the Vdc value in the VSIN parameters (default is zero). Vdc is also used to calculate the initial DC solution. The rest depends on the circuit topology.
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
Only gmin, no error, no warning apart in the spice error log.
:-(
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 ;-).
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
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
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.
If you don't like me, add-me to your ignore list.
BTW: Everything is money based, in your way to see the life ?
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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.
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).
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.
QUCS is an open source circuit simulator which is developed upon, and at every version release the first port is to: the Linux O/S. For some people this is a feature and not a bug. You can download the source code and compile it yourself, if you don't trust 3rd party binary executables.
Qucs project: F.A.Q.
Qucs project: F.A.Q.
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.
You can persuade ltspice to do square waves by just putting in a very high sine voltage.
It just clips the sine wave and becomes a square wave.
Not so useful if you just want a small signal square wave though.
It just clips the sine wave and becomes a square wave.
Not so useful if you just want a small signal square wave though.
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.
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
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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