Anyone know a decent schematic drawer for linux?

[Mike]

I generally knock up my circuits with lined paper and a biro; this works fine for designing circuits before I build them, but is pretty inadequate for sharing on my blog. I use Ubuntu and have tried most of the offerings I can find in the standard repositories with basic search terms, none of them seem to work very well at all. What I'm looking for is the ability to draw diagrams for circuits using things like discrete components, logic gates, generic packages (e.g a box with 555 as a label then the ability to add inputs/outputs manually) etc. Having common chips pinouts would be lovely, but I'm not expecting that.

Does anyone know of a program that somewhat matches these requirements?

Thanks,
Mike

[UAirLtd]

Well, this may not be optimal, but I can tell you that it works: KiCad, an open source (cross platform) PCB design program. Its main purpose is to design PCBs, so one part of the application deals with drawing the schematics. Naturally it includes the ability to define custom components (and define the pins and labels manually), and also has a few common chips within its library already. Some features you might find handy is the ability to generate BOM lists, and doing ERC checks (automated electrical connection checks that will warn you if you tried to connect two outputs together, or forgot to connect a power supply to a power rail for example. These rules are customizable and use the pin type you define while creating a component: input, output, passive, bidirectional, power in, power supply, open collector, open emitter, etc.)

The downside is that KiCad has a moderate learning curve, and probably isn't the quickest and most convenient schematic designer conceivable, and a few quirks to get used to (newest version of KiCad already greatly improved).

TO give you an example of what the resulting schematics look like, here's one from our Forebrain (LPC1343 development boards). Forebrain's PCB was designed on KiCad, this is a printout directly from the schematic editor of KiCad, no additional changes were made to the file: http://www.universalair.co.uk/sites/def ... ematic.pdf (PDF file). This was generated directly via the print function of the schematics editor (via a PDF printer), with the option to print the sheet reference and title block on, and in color.

Of course, KiCad isn't the only PCB designer with a schematic editor you could use, you can also try circuit simulators and such. There are a good range of open source and free commercial packages such as gEDA, Electric, XCircuit, Eagle, DipTrace, Fritzing, KTechLab, QUCS that might be applicable for your situation. I don't know the status of any of these, I've only used KiCad and Eagle.

[Osgeld]

my main problem with kicad this week is the darn thing doesnt export to images right, or to pdf at all, making it a bit of a pain if you want to share.

Though it usually functions, its learning curve is almost not worth it, as it always leaves me aggervated

A more simple, in every way program is Dia, its a diagram editor for flow charts and what not but does have a small array of electronic symbols

[UAirLtd]

Yeah, the built-in PDF export is sucky. I use doPDF, a simple and free PDF printer, and just use Kicad's print function, which gets things right. For images, I either screen-cap it directly, or crop it out of the PDF.

Learning curve is an issue, but I've been designing all of our PCB products for some time now with no big issues. These are the PCBs that are flying quadcopters, so that's how much trust I put in KiCad to get things right.

[Osgeld]

Yeah, the built-in PDF export is sucky. I use doPDF, a simple and free PDF printer, and just use Kicad's print function, which gets things right. For images, I either screen-cap it directly, or crop it out of the PDF.

Learning curve is an issue, but I've been designing all of our PCB products for some time now with no big issues. These are the PCBs that are flying quadcopters, so that's how much trust I put in KiCad to get things right.

heck if I just could get it to print I would be happy, whenever I click print, most of the component labels and half my nets vanish in the result, when I go back to the editor its all that way too! Highly irritating, both in ubuntu and windows7.

bugs are bugs, oss is oss, it will get smoothed over, and its nitpicky to when it used to crash after working on a design all night, causing me the "ki cad twitch" where I save after every change.

As far as learning curves go, yea it has one, every EDA has one, and if you want to do more than draw a diagram you will have to sit down and learn it... after all its pretty powerful stuff, draw a schematic, add footrpints plop it on a board, route traces, holes and drills, mail it off and in a few days/weeks have a professionally made and machined physical item in your hand.

Its not msPaint, though it functions most of the time, and once you have the fundamentals down its not that hard to switch outside of learning where crap is in menus

[Mike]

Thanks for the recommendation; kicad seems better than the other ones I've tried. It does feel a bit like I'm using thunderbird 2 to just nip down the corner shop, but it's nice to know I can use all the other features if I feel like it. The plot to svg feature seems to work fine for me, with the slight issue that it leaves the background transparent.