Feature: circuit diagram

[akshaybabloo]

It will be good to have a way to create circuit diagrams using D2.

[alixander]

hey @akshaybabloo thank you for the suggestion! Do you have an example of what you mean?

[akshaybabloo]

@alixander Certainly. Consider the following example of a circuit diagram (made with Autodesk Fusion 365):

Is shows that a 9v battery connected to a resistor to step down the voltage to light up the LED

The only difference between US and NON-US is how the resistor is denoted.

I tried to do this via D2, and this is what I got:

direction: right

classes: {
  resistor: {
    shape: rectangle
    height: 10
  }
}

9v -> 350k -> led -> 9v
350k.class: resistor

https://play.d2lang.com/?script=gkevlUIRKDi5uKCpwEqhmktBoSi1OLO4JL8IwlNQAIeClQJIT2Jeek4qWBASEVYKhgZcCgq1XLVcXJZlCrp2CsamBtkgOic1BURZlnGBRPTAFljBjeYCBAAA__8%3D&layout=dagre&sketch=0&theme=0&

I think for this we would need the following:

1. Right angled connections (sharp edge connection)
2. As a starting point, basic analog icons - see https://www.ultralibrarian.com/2020/11/24/electronic-component-lists-and-schematic-symbols-ulc
3. Labels that can be put outside of the icon

Digital icons can be added later once you have a proof of concept

[alixander]

direction: right

classes: {
  resistor: {
    shape: image
    height: 30
    width: 60
    icon: https://b2523400.smushcdn.com/2523400/wp-content/uploads/2020/11/image19.png?lossy=1&strip=1&webp=1
  }
}

US: {
  style: {
    fill: transparent
    stroke-dash: 2
  }
  9v -> 350k -> led -> 9v
  350k.class: resistor
}

https://play.d2lang.com/?script=RJLBbsMgEETv-xVzyi0GnKaSV3L7EVU_wLFRYtUGBCRRVfnfK5Y0Pa1mDsvyZp7xMmLBSfRoAeOHgGjTnLKPVQFCgTGvw9mKUUNgHLRI2cl4raqkwbjkHBIrdWqP7eFF6yat13QZJ9eMflUPU93DfvQuW5fVNSx-mJJqdauVMUpeM10T3Pl98Sl992aXcpxDb3Z3ewq9IWCjjejzox4qDP9uLsVjCJ4wROty_cl_HIxWFgDdDfs3HI76q8zFTmV0N4J4jaDhJxTa6DcAAP__&layout=tala&sketch=0&theme=0&

it's pretty close. this type of diagram cannot be done in elk or dagre btw, because they only do hierarchical diagrams.

i think implementing ports is all that's needed: https://github.com/terrastruct/d2/issues/628

@akshaybabloo are there any comparable tools that you can create circuit diagrams with text?

[akshaybabloo]

Not that I know of @alixander

[akshaybabloo]

Also, the ends are not really connected to the resistor there, it's just hovering. It would be nice to have some internal icons that can do that.

[alixander]

just need ports (can then specify to only route through the left and right sides of the icon)

[BarryNolte]

Tools to create schematics, off the top of my head:

1. KiCad
2. OrCad
3. Altium
4. Proteus
5. Fusion 360
6. CircuitMaker.com

[alixander]

can you generate with text in any of these? @BarryNolte

[BarryNolte]

I think what you want is a 'net list'. https://en.wikipedia.org/wiki/Netlist. They all probably produce a net list; some might read them. I don't think it's a super well-defined standard, otherwise there wouldn't be a lot of discussion on converting files from one EDA package to another, which is the evergreen topic on electronics message boards.

[akshaybabloo]

Most of them use a combination of XML and binary

[alixander]

sorry i meant are any of these tools text-to-circuit-diagram. not whether they can export to text.

could be a good opportunity to expand d2 with no much more extra work if a comparable solution doesn't exist yet and there's demand for it

[BarryNolte]

I think there are some netlist -> html/svg projects around.

[alixander]

oh interesting, yeah: https://github.com/nturley/netlistsvg#examples

looks like they use ELK too.

[BarryNolte]

Yup, just found that one too.

[bo-ku-ra]

Verilog

[dtmaidenmueller]

For scripted schematic image generation, there's this library: https://github.com/cdelker/schemdraw

[alixander]

that one seems quite good. i'm going to close this then as not something D2 should focus on.