Any Free Block Diagram Programs?

[rcbuck]

Are there any free simple block diagram drawing programs available? I don't mind using an online program as I only need something like this once or twice a year.

I found several good free programs. The problem with them is they apparently don't have tools to let you add your own shapes. For example, if I want a couple of objects like shown in the attachment. There should have to be a way of drawing lines between the created objects and the standard built-in blocks that the program has.

I have a PC layout program that I currently use the schematic drawing part of the program for creating my block diagrams. However it is not the best solution as it isn't really a drawing tool. For instance, if you look at the NO relay contact you see a small "X". This indicates a connection hasn't been made to that terminal of the part. If I create a simple rectangle with the drawing tool and then draw a line from the relay contact to the rectangle, the "X" doesn't disappear. This is because a drawn line is not a real connection. The rectangle I created is not a real part so it doesn't have the "X" connection point. Therefore I can't use the connection tool to draw the line between the relay and the rectangle. I actually can but the connection line changes from black to red to indicate one end is a dangling connection.

In the past I have used the drawing tool to create what looks like the relay contacts and then the "X" doesn't exist. However, there is no way to save the created contacts as an object that I could use in my next block diagram. I'm hoping one of the block diagram drawing tools would allow you to create objects to save to a library for future use.

[TimNJ]

I tried draw.io (now called diagrams.net, apparently)...and thought it was reasonable. I still found it a little finicky, but still better than trying to do it in PowerPoint, in terms of re-arranging and adding to the diagram.

Something like Latex would probably make the cleanest, most (stylistically) consistent diagrams though.

[jpanhalt]

I am not sure what you mean by "block diagrams."  Do you mean something like a flowchart w/ or w/o arrows?  I use Draw IO that is typical Google and works well.  Haven't used it in awhile, so it may have gone the way of Sketchup.

Edit:  Just read Tim's comment.  Oh, heck.

[rcbuck]

See attachment for what I mean when I say block diagrams.

Latex is not a drawing tool. I guess it somewhat is if you want to learn to write code to do something that a graphical tool does with drag and drop.

[Benta]

For this kind of thing I use KiCAD (other schematic layout programs will also work) and use hierachical sheets for block diagrams, which means you can enter both blocks and components.
The upside is, that if you want to upgrade your block diagram to a complete schematic later on, you can just enter the different sheets ("blocks") later on a draw the schematic.

[Benta]

See attachment for what I mean when I say block diagrams.

Latex is not a drawing tool. I guess it somewhat is if you want to learn to write code to do something that a graphical tool does with drag and drop.

For something as simple as that, I'd just use the classic MS Paint. Not installed per default today, but still available.
The Linux pendant is Kolourpaint.

[TimNJ]

See attachment for what I mean when I say block diagrams.

Latex is not a drawing tool. I guess it somewhat is if you want to learn to write code to do something that a graphical tool does with drag and drop.

Not natively, but TikZ can make some nice textbook-style diagrams. I suspect that's what a lot of my professors used in college.

I'm not a Latex fanboy or anything, but the few times I used LyX (Latex editor), I was really happy with the output. Definitely took longer (as a novice), but the results are consistent. (That's pretty  much the point of Latex, IMO) That said, I don't bother with it in the professional world, at least for what I do. The setup time is too much for me.

[Bud]

Have you tried Digikey Scheme-It  ? 

[jpanhalt]

Try Drawio or whatever it's called today (https://app.diagrams.net/ ).  See attachment.

[TimNJ]

Have you tried Digikey Scheme-It  ?

I'm playing around with it and it seems really solid! Thanks!

I like that it lets you hook together circuit symbols with block elements with no questions or complications. Sometimes that's exactly what you need to do.

[Bud]

Yes. I came across it by accident, i did not see Digikey promoting it anywhere. I think it has its place. And it produces aesthetically nice diagrams.

[Ario]

Draw.IO is definitly a good option. It can also be used in various other fields, apart from electronics.

[palpurul]

In my opinion any CAD program used for PCBs are the best.
I don't want to learn a new software 

[EPAIII]

I have made a large number of block diagrams for various documents that I have had to write. Mostly I have used a 2D CAD program that I have used for decades now, FastCAD or an earlier version, EasyCAD. Almost any 2D CAD program will make easy work of producing such simple diagrams with blocks, simple symbols, arrows for signal flow, and text for labeling. 2D CAD programs will have a grid that makes the placement and alignment of the elements a snap (pun intended).

I have, on occasion, used Microsoft Paint but it did slow things down a bit from the speed with which I could make the same drawing with the 2D CAD program. And it is more difficult to edit a Paint drawing due to it's pixel nature as opposed to the object nature of CAD drawings.

EasyCAD and FastCAD are still available, but they do have a price. I have learned a number of 2D CAD programs and can easily say that EasyCAD and FastCAD are the easiest to learn of any that I have used. I made my first drawing with EasyCAD after only an hour of reading and playing with the various commands.

There are a number of 2D CAD programs that are free.

[david77]

I've used SPlan for block diagramms quite a bit.

https://www.electronic-software-shop.com/lng/en/splan-80.html?language=en

Very easy to create symbols and lets you mix symbols, components and text easily. AFAIK it also comes with some ready to use symbols.
Practically no learning curve if you've ever used another Windows CAD tool.

[TERRA Operative]

LibreOffice Draw can do it, it's an open source version of Microsoft Visio.

[mfro]

...Latex is not a drawing tool...

There's actually not much you can't do with LaTeX

Code: [Select]

\begin{circuitikz}
\ctikzset{bipoles/cuteswitch/shape=emptyshape};
\ctikzset{bipoles/cuteswitch/thickness=0.5}
\draw
(1,1) node[bnc,font=\tiny,align=center](B1){J1\\ANT} --
(2, 1) node[cute spdt up](Sw){};
\draw (Sw.cin) node[draw, ocirc]{};
\draw [<-] (Sw.cout 1) -- ++(0, 0.5) -- ++(1.5, 0) [-] node[ground]{};
\draw [<-] (Sw.cout 2) -- ++(0, -0.25);
\draw (B1.shield) node[ground]{};
\end{circuitikz}


[rcbuck]

I guess I will stick with my PC program even though it is slightly slower than I like for creating objects. What palpurul said may be in fact true. I will also see if I can find a 2D CAD program to play with.

I started this layout yesterday and it took about 2 hours to put together.

[SiliconWizard]

I've used SPlan for block diagramms quite a bit.

https://www.electronic-software-shop.com/lng/en/splan-80.html?language=en

Very easy to create symbols and lets you mix symbols, components and text easily. AFAIK it also comes with some ready to use symbols.
Practically no learning curve if you've ever used another Windows CAD tool.

I can second that. If you want to draw *publishing-quality* schematics - it's either sPlan, or LaTeX. The later requiring a bit more learning.

As some others here, not sure what the OP meant by "block diagram". They show a piece of schematic that is not really a block diagram.

For block diagrams, I typically use yEd graph editor these days: https://www.yworks.com/products/yed (free but not open source.)
The number of "shapes" is limited though, and I'm not sure you can create your own.

One editor I used before that was Dia ( http://dia-installer.de/index.html.en ), kinda clunky UI, but it works, exports to many formats, and there are a number of existing libraries, and you can of course make your own. Hasn't been updated in quite a while though, so it looks like a dying project.

[PaulAm]

If you have Linux, an old school program that I use is xfig.  Pretty simple to use and it 's oriented toward line art (as opposed to a paint or CAD program)  Make boxes, lines, add text,  combine objects into a compound object, move them around, scale, etc.  It also has some available libraries for common objects (architectural, electrical, etc)

It's not a cad program, but I will use it for simple schematics when I won't be making a pcb.  It's great for block diagrams.  Pretty easy learning curve.

[rcbuck]

As some others here, not sure what the OP meant by "block diagram".

Did you not see Reply #3 and #17?

Maybe I should have said "semi-block diagram"?

[tooki]

I tried draw.io (now called diagrams.net, apparently)...and thought it was reasonable. I still found it a little finicky, but still better than trying to do it in PowerPoint, in terms of re-arranging and adding to the diagram.

I recently used it for a project and after I figured out one or two key concepts, found it very nice to work with.

I am not sure what you mean by "block diagrams."  Do you mean something like a flowchart w/ or w/o arrows?  I use Draw IO that is typical Google and works well.  Haven't used it in awhile, so it may have gone the way of Sketchup.

It’s not a Google product, whatever gave you that idea?!?

[free_electron]

inkscape

[georges80]

dia is pretty easy to use and has a lot of shapes already created. You can create/add new shapes.

https://sourceforge.net/projects/dia-installer/

cheers,
george.

[rcbuck]

This is the type of "block" diagram I meant. Something like you would see in the service manual for a commercial Amateur Radio transceiver. This is the completed diagram I needed to have in front of me before I began drawing the actual schematic and designing the PCB. I am now working on the schematic. PCB will follow.

I believe my PCB program is probably the best tool to use. Since I only do this a couple of times per year I can put up with the small idiosyncrasies when creating a block diagram.