Circuitlab Simulation - anyone using this regularly?

[rx8pilot]

I briefly looked at circuitlab, a cloud based simulator. There have been spotty conversations about it here on EEVBlog and I was wondering if anyone is using it and why.

On the surface, it is slicker and prettier than LTSpice but it is hard to tell if it is better/worse as a tool to solve typical problems. In general, I have only used LTSpice to simulate relatively small sections of my circuits to get me in the ballpark. I have not done any real serious simulations. Part of that is because I am not particularly skilled with the tool and the small things take a long time for me. If this Circuitlab is easier to use, it may offer a more gentle learning curve and allow me to pursue more sophisticated designs.

Any users here on the blog with feedback - good or bad? They seem to marketing to professionals, so I would guess the product should be reasonably advanced.

https://www.circuitlab.com/

https://youtu.be/f52GV1IpwVk

[signality]

I started using CircuitLab a few weeks after it launched in Feb 2012 when it still offered unlimited free usage.

It developed quite quickly to start with but has since stagnated.

Pro:

Easy to learn and easy to use;
Nice looking schematics with reasonable (schematic and plot drawing/pdf type format only plus simulation results in csv) export options;
The simulator does most things OK and some things very well (it's only one of two I know of that correctly handles Laplace operators in a feedback loop but those things are pretty esoteric).
Runs on most platforms.


Con:

A bit thin on documentation.
No support for importing vendor .subckt (subcircuit) defined models;
Limited support for vendor .model defined models;
No support for subcircuit/heirarchical block circuit creation.
No support for schematic/spice/PCB netlist import/export from/to other tools;
No PCB support.
Very limited user schematic symbol creation support;
Poor forum support from the CL team itself  ;
Expensive for what it provides (LTspice is way, way ahead as a simulator tool with schematic capture and of course is completely free and has an excellent Yahoo user group at https://groups.yahoo.com/neo/groups/LTspice/info plus LTwiki.org).

I don't know if they still do this but I was very put off by their rolling credit card billing: you had to actively opt out to stop your subscription being renewed automatically.

A big problem with CL is that it won't talk to anything else so all work done in CL stays completely in CL.


An alternative?

If you want a free tool that supports schematic capture, spice simulation and PCB layout (and plays nicely with other tools) then you could try EasyEDA.com.

It also has a responsive team with pretty good forum support.

Apart from supporting hierarchical design and having only limited functionality on touchscreen platforms, EasyEDA does everything that CL doesn't do and a lot of what LTspice does do.

It has the rather nice feature that you can import LTspice schematics (.asc files) straight into EasyEDA so you can progress designs simulated and developed in LTspice into simulation schematics with full BoM support and then pass them into PCB layout without having to redraw the schematics from scratch.

It doesn't support all of the LTspice specific simulation models that are available in LTspice but it does support a useful amount.

There's a nice example of an LTspice simulation schematic imported (and even re-simulated!) into EasyEDA here:

https://easyeda.com/example/Uberclamp_simulation-RzsmgyQ8q

and then turned into a non-simulation schematic and PCB:

https://easyeda.com/example/Uberclamp_Schematic_PCB_and_BoM-r4YgysK2k

[Bud]

If you want a free tool that supports schematic capture, spice simulation and PCB layout (and plays nicely with other tools) then you could try EasyEDA.com.

Thanks for the link. Lost interest the moment I saw it is cloud based...

[rx8pilot]

The cloud based solutions are nuts for this type of work.

I would love to see a rent-to-own model where you can pay a modest fee each month like a cloud service but you would be gaining equity in a stand-alone version. If you want, the the option to buy a fixed version that you own minus what you already paid in monthly 'rental'.

[PCB.Wiz]

The cloud based solutions are nuts for this type of work.

Agreed.

On the surface, it is slicker and prettier than LTSpice but it is hard to tell if it is better/worse as a tool to solve typical problems. In general, I have only used LTSpice to simulate relatively small sections of my circuits to get me in the ballpark. I have not done any real serious simulations. Part of that is because I am not particularly skilled with the tool and the small things take a long time for me. If this Circuitlab is easier to use, it may offer a more gentle learning curve and allow me to pursue more sophisticated designs.

LT Spice has just released LT Spice XVII
http://www.linear.com/designtools/software/
Which represents a further improvement, and it is still hard to beat for ease of use & quick results.

It does have a nice waveform viewer, and that can import .RAW files, and we have done a couple of projects where we exported data in RAW and use LT Spice as the Viewer, with Zoom/measure/print.

LTSpice is not great as a general schematic or PCB front end.
Yes, it has NETLIST options, and a BOM, but is patchy/buggy in field entry/export so has limited real use.

KiCad is in the process of adding a Spice engine, so if you need better Schematic-side and PCB interface, than LTSpice, that is worth following.
The main issue will be Library support, but that will come, and will be broader than then Linear-Centric LTSpice.

[signality]

AFAIAK, all Kicad are doing is adding a nice front end to hook Kicad schematics into ngspice as the simulaton engine.

Actually it has been possible to use Kicad with ngspice for many years but it is horribly clunky.

Whether it'll be possible to use it with LTspice in the sort of way that DesignSpark can remains to be seen.

In fact EasyEDA uses ngspice as the spice engine. Ngspice is pretty good but it is not as slick nor seems to be as well behaved in terms of convergence as LTspice (which in MHO, is up there with SIMetrix as about the best there is).

There are rumours that there may be a local client in the pipeline from EasyEDA. Run it on your local machine and maybe pay for things like access to special libraries, advanced autorouter, specialist simulation features such as fast SMPS simulation or maybe just design services and symbol/footprint/model creation.

That may change a few people's view of EasyEDA.


I don't have a problem with the extent of the libraries in LTspice since models are easy to find and import and it runs just about all the unencrypted libraries and models that are freely available from vendors.

That's not to say that such models are always as good as they could be but that is not an LTspice issue in itself. SIMetrix spend a lot of time debugging many of the vendor models that they ship in their libraries. Many of the vendor models can be fixed in relatively simple ways but it can sometimes get in you a tangle with copyright and EULAs.

I haven't seen any big performance increase with LTspice XVII and, at least for me, in a few relatively minor ways it's slightly behind LTspiceIV in terms of productivity. I also must have missed something as I haven't found the new IGBT model mentioned on the LT sites. The ability to specify library locations is nice but you seem to have to explicitly tell it the path to every sub-folder in a remote 'sym' or 'lib' folder even if it's a direct copy of the installed folder, which seems a bit naff. Also not sure quite what happens with a field update now but I've not been running it with remote libs for long enough to know.

[technotronix]

I don't have any experience with circuitlab, but will look forward to use it in future.