Thoughts on new simulator - QSpice

Moderator
Joined 2011
To all bit-heads:

Not everyone wants to screw around with computers like geeks.
Some just want to use them as a tool. You know, like a hammer, a can opener, or a toaster?
I've used every widely available commercial computer around, since starting with the IBM 360.
I just want a properly working tool to use for doing what I need to do.

And by the way, I don't know what planet you live on, but having been in both industry and research
for many years, most users did all their work on individual Windows machines (for better or worse).
You know, they were using the software and hardware as tools, to get their work done?
 
  • Like
Reactions: 1 user
In the 1990s I liked the pspice UI and how it worked overall, but I found myself learning Switchercad, er, LTspice despite its clunky UI. I did recently get up to speed on Kicad 7, so I know it's possible for me to learn new things even while approaching (ahem) retirement age.

But now there's this, and oh my gosh, I dunno ...


Actually, it looks quite easy and straightforward, especially coming from THAT guy.
 
  • Like
Reactions: 1 user
AX tech editor
Joined 2002
Paid Member
More fragmentation of the spice community is a gift? Binding to OS's that are commercial and not generally used by the academic and research communities is a gift? The reason the spice code was so central for decades was because it was good enough, open and written in standard languages like Fortran or C that could be used on any platform by anybody. Certainly some users will benefit from slick user interfaces particularly if it is adapted to their area of interest but it hasn't served the interests of the spice community as a whole to have multiple solvers that aren't platform independent with some being proprietary. There might have been more of a case if the solver wasn't relatively straightforward to maintain and develop in an open manner by interested users. Whatever, the change happened decades ago and probably only bugs oldies.
I think it has served the Spice community well. I never understood why some people would forgo the incredible deal of a free powerful spice simulator just because they have an emotional aversion to this or that OS. It just doesn't make sense, unless you really don't need a sim at all.

jan
 
  • Like
Reactions: 4 users
AX tech editor
Joined 2002
Paid Member
In the 1990s I liked the pspice UI and how it worked overall, but I found myself learning Switchercad, er, LTspice despite its clunky UI. I did recently get up to speed on Kicad 7, so I know it's possible for me to learn new things even while approaching (ahem) retirement age.

But now there's this, and oh my gosh, I dunno ...


Actually, it looks quite easy and straightforward, especially coming from THAT guy.
Did you see that .bode command?? That alone is worth a lot.
And the wiring of the parts, just run the cursor through the part and the wires automagically connect to the part endpoints!
There's a lot of smart improvements here in the intuitive department. I want it!
Where can I download it?

jan
 
  • Like
Reactions: 1 user
just because they have an emotional aversion to this or that OS
No one said they don’t like Windows in this thread, the discussion has been quite rational. But not everyone chooses Windows as their main OS.

My main PC is a Mac. I don’t know if you have used LTSpice on macOS, the GUI has diverged a lot from the Windows version and has fewer features. I actually bought a cheap Windows laptop just for running it (it’s tool old to run a Windows VM).

So to bring back the discussion to QSpice. Cross platform tools have really matured. My point is that you could put the effort to build the GUI cross-platform from the start, and easily support all platforms going forward. I see it as a missed opportunity.
 
No one said they don’t like Windows in this thread, the discussion has been quite rational. But not everyone chooses Windows as their main OS.

It is more a question of the appropriate tool for the job and perhaps understanding why open/free/academic/research simulations packages like the original spice are rarely developed on Windows with many never being ported to Windows judging the time and effort too large to overcome the many non-standard and gratuitously complex things MS does to create lock-in on their platform. Commercial simulation software aimed at more passive users/consumers is almost the complete opposite in being strongly focused on Windows and for good reason. They are different platforms for different kinds of software and different kinds of users as can be seen in this thread.

Just as working with simulation software on Windows isn't well supported the basic stuff like browsing, email, organising, touch screens,... isn't well supported on platforms like linux whatever enthusiasts may claim. I tried for a few years to use a 17" Apple laptop for software development and general computing in the lab, office, lecture theatre, visiting clients but Apple's focus was progressively moving away from that sort of thing (I still ran large simulations on linux clusters having never come across a Windows cluster although they do reportedly exist). Now I carry a small Windows touch screen laptop and didn't even bother to install linux as an alternative boot option on my latest one. On the other hand the desktop/workstation is linux with Windows a very rarely used boot option until MS decided I needed to buy a wholly unnecessary small daughter card to run Windows 11 when I stopped using it at all (yes I know I could get round it). I will of course be forced at some point in the future to run Windows to support some aspect of work but hopefully it will be after I buy my next workstation.

Perhaps I should mention that like many researchers my workflow tends to involve a set of interacting modules for modelling, simulation, plotting, documentation and the like. Having some modules on different platforms isn't a practical option. I run spice in batch mode creating the network definition and displaying the results in different modules. This is a different way of working to those that launch a spice gui and work interactively within it. There are pros and cons for both approaches which can vary substantially with both the task being addressed and the user's knowledge and capabilities.
 
  • Like
Reactions: 3 users
Member
Joined 2019
Paid Member
Today, I took the plunge and tried QSPCE. First half an hour was frustrating, but after that point it was really an excellent experience in drawing new schematic. It is incomparably easier, better and faster than drawing with LTSpice. Adding any model through directive, builds symbol and embeds model into the file. So, sending your simulation schematics to someone else avoids any problem with missing models.

There is probably an option to add models to the system libraries, but I’m only several hours into QSPICE.

However, I was struck with the first bug found. I can run all demo simulations just fine, but trying to run my file makes QSPICE to complain that it can’t find file ‘none’. Reported that to QSPICE author.

My impression is that we can expect great things from this simulator.

Qspice.png
 
  • Like
Reactions: 1 users
Administrator
Joined 2007
Paid Member
I've been having a play for a while now but its a steep learning curve. The interface for drawing the schematics is great though.

Here's the ACA. The folder has a bjt version as well:

(I will ask Jason if he can add .qsch files to the list of accepted file types)

Screenshot 2023-08-26 190121.png
Screenshot 2023-08-26 190101.png
 

Attachments

  • ACA FET and BJT Version.zip
    3.9 KB · Views: 67
  • Like
Reactions: 1 users
  • Like
Reactions: 1 user
Member
Joined 2019
Paid Member
Not really following you on that one. Clicking any of the .qsch files you have should open QSpice.
All files open without any problem. It is that Qspice complains, on already opened file when I press green ‘Run’ (simulation) button that there is no file or “Could not open file "none".

Edit: just found the cause. It was an opamp imported model causing the problem. I’ll have to try again.
 
Last edited:
Today, I took the plunge and tried QSPCE. First half an hour was frustrating, but after that point it was really an excellent experience in drawing new schematic. It is incomparably easier, better and faster than drawing with LTSpice. Adding any model through directive, builds symbol and embeds model into the file. So, sending your simulation schematics to someone else avoids any problem with missing models.
If you want to make that rectangle into a "real" opamp symbol, this video will show you how:
 
Member
Joined 2021
Paid Member
As the electronics ignorant that I still am, I am infinitely grateful to those who produce such tools for free. I would even pay $50-100 a year to use them.
What I cannot justify is paying thousands of dollars a year to Altium or Autodesk for tools I need and use as an amateur.
 
  • Like
Reactions: 1 users