Years ago I worked for another company, where I had access to SIMETRIX. I did some CLass D simulations (mainly my self osc. class D project SOCD what you can find here in this Class D folder - omg.. how many years have passed! about 7! I 'm getting older too, btw...).
Now since the company has shut down its European sites, I can only continue with LTSPICE. Trouble is, that I get many issues, which I do not remember having seen that severe on SIMETRIX: convergence issues, "time step too small",.... If I use MAX961 model from their website in my sim, the sim won't even start, claiming some model-internal convergence issue. Same for OPA134 etc... sometimes LTSPICE will even freeze, so it is recommended to save every important circuit change prior to starting the sim.....
How do you solve those issues ? Is there any better free simulator that does not have these issues as severe?
I' d like to concentrate on the circuit, not on the simulator's specific needs. Besides that, everything seems VERY slow on LTSPICE, although I only worked on an i5 laptop so far. I 'll install LTSPICE on my shiny new i7-8700K / 32GB DDR4 / M.2 SSD system soon. During my SIMETRIX time, I had a mobile core 2 duo and everything was running almost smoothly - how can that be if the computer was as slow as a snail compared to even skylake i5? I am working on a full bridge using UCC21521C or similar, SCT3030AL, MAX961 and input filter usind OPA134. Goal is to have the whole circuit in one sim using the intended components, not just functional blocks.
Any ideas?
Now since the company has shut down its European sites, I can only continue with LTSPICE. Trouble is, that I get many issues, which I do not remember having seen that severe on SIMETRIX: convergence issues, "time step too small",.... If I use MAX961 model from their website in my sim, the sim won't even start, claiming some model-internal convergence issue. Same for OPA134 etc... sometimes LTSPICE will even freeze, so it is recommended to save every important circuit change prior to starting the sim.....
How do you solve those issues ? Is there any better free simulator that does not have these issues as severe?
I' d like to concentrate on the circuit, not on the simulator's specific needs. Besides that, everything seems VERY slow on LTSPICE, although I only worked on an i5 laptop so far. I 'll install LTSPICE on my shiny new i7-8700K / 32GB DDR4 / M.2 SSD system soon. During my SIMETRIX time, I had a mobile core 2 duo and everything was running almost smoothly - how can that be if the computer was as slow as a snail compared to even skylake i5? I am working on a full bridge using UCC21521C or similar, SCT3030AL, MAX961 and input filter usind OPA134. Goal is to have the whole circuit in one sim using the intended components, not just functional blocks.
Any ideas?
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You could try this if you can get by with the circuit size restrictions:
Download Free Demo - SIMetrix/SIMPLIS Elements
Download Free Demo - SIMetrix/SIMPLIS Elements
There is a whole thread here on how to get started in LTspice. Lots of help to get you going, just search and get in.
Edit: if you are search-challenged:
Installing and using LTspice IV (now including LTXVII). From beginner to advanced.
Jan
Edit: if you are search-challenged:
Installing and using LTspice IV (now including LTXVII). From beginner to advanced.
Jan
Quote:
"Goal is to have the whole circuit in one sim using the intended components, not just functional blocks."
A simulation in full detail includes many "bells and whistles" that have no impact on the results of any possible type of simulation for checking any possible figure of merit of the circuit. But these "bells and whistles" slow down the simulation, increasing the time required for closing the process of topological optimizations by trial and error. However, what could be required when using not previously known parts is to test such parts in breadboard in order to identify the obscure or undocumented details that matter for a particular circuit (details not always found in simulation models). On the other hand, when known parts are used, simplified simulation models are often enough.
"Goal is to have the whole circuit in one sim using the intended components, not just functional blocks."
A simulation in full detail includes many "bells and whistles" that have no impact on the results of any possible type of simulation for checking any possible figure of merit of the circuit. But these "bells and whistles" slow down the simulation, increasing the time required for closing the process of topological optimizations by trial and error. However, what could be required when using not previously known parts is to test such parts in breadboard in order to identify the obscure or undocumented details that matter for a particular circuit (details not always found in simulation models). On the other hand, when known parts are used, simplified simulation models are often enough.
I want to avoid having to go to the lab, solder and build a prototype, maybe risk costly explosions etc.. That is why I want to optimize on the computer as far as possible, and maybe after that have some other guy build the amp and get happy with it.
You should know that LTspiceIV is more stable than LTspiceXVII. I tried about 30 spice programs before switching to LTspice. There are several subtleties when using LTspice. Of course, Simetrix is more resistant to not very good models, but difficulties can be overcome. There is also a large group of fans of LTspice and it helps to cope with the difficulties of modeling. I strongly recommend to join Yahoo! Groups
I also made a collection of models:
For LTspice users. Libraries of models, examples, etc
I also made a collection of models:
For LTspice users. Libraries of models, examples, etc
Bordodynov, I am trying to use your libraries and symbols (I am specifically looking for a depletion mode MOSFET) but have difficulties. I have my own lib and sym libraries, and I copied your symbols, cmp and lib directories there. But LTspice (XVII) does not show me the subfolders.
For instance, in my folder ....\cmp I have a subfolder ....\cmp\ZZZ with your stuff but when I try to select a part, the \ZZZ is not shown in the selector box. What am I doing wrong?
Jan
For instance, in my folder ....\cmp I have a subfolder ....\cmp\ZZZ with your stuff but when I try to select a part, the \ZZZ is not shown in the selector box. What am I doing wrong?
Jan
MOSFET depletion mode models are stored in the same location as regular MOSFETs. Put on the circuit symbol depletion mode MOSFET and select the transistor.
In my page it is written where there should be additional models and symbols. Read it. Those. In the new version of the program (LTspiceXVII), additional libraries must be located in the My Documents folder (or as I have the Documents) (not in the Program file).
Only my standard.xxx files should be in the CMP folder (make a copy of your own). If you have your own original models, which I do not have, then add to my files. You can also send your files to me and I will add the missing models to mine (unless of course you don’t feel sorry). I try to have all the models that are actively used by LTspice users.
Folder .... \ My document ... \lib\sym\ZZZ contains only my, additional symbols.
Additional models contains a folder ..... \ My document ... \lib\sub.
In my page it is written where there should be additional models and symbols. Read it. Those. In the new version of the program (LTspiceXVII), additional libraries must be located in the My Documents folder (or as I have the Documents) (not in the Program file).
Only my standard.xxx files should be in the CMP folder (make a copy of your own). If you have your own original models, which I do not have, then add to my files. You can also send your files to me and I will add the missing models to mine (unless of course you don’t feel sorry). I try to have all the models that are actively used by LTspice users.
Folder .... \ My document ... \lib\sym\ZZZ contains only my, additional symbols.
Additional models contains a folder ..... \ My document ... \lib\sub.
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