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I'm a VHDL guy for work, so please forgive if this question is dumb.

I asked a buddy to lay out a board for me. The maximum voltage is 2 kV. He said he can't do it because the voltage is too high. (I offered to pay him too so that's not the problem.) However, I don't buy that because:

  1. The highest rated voltage of any component is 650 V, and I never exceed that. Actually, I keep everything lower than roughly 80% of the rated voltage. I'm ganging devices in series, adding 1M resistors across the collector-emitter junction to share voltage evenly, etc.

  2. As long as I keep conductors far enough apart, such that the breakdown voltage between them is more than, say, 10x the potential difference, I don't see how arcing is even possible. Also, I put snubbers across every junction that sees a large voltage difference, so brief spikes should not be possible.

  3. It's trivial to break the design up into smaller boards, so that no individual board has more than 650 V across it. Then I can add an extra cm or whatever between boards to prevent arcing.

So I downloaded KiCad and laid out a few simple boards. Now I'm tackling the design I care about.

My question is how to automate point #2: Is there a way to tell KiCad, "Node 2 has a maximum magnitude of 650 V relative to ground. Node 3 has a maximum magnitude of 50 V relative to ground. So route the traces any way you want, as long as there's 7 kV (= 10 * (650 + 50)) of clearance between nodes 2 and 3"? If so, how does one do this?

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    \$\begingroup\$ 600 + 500 does not equal 7000. Don't use an autorouter. \$\endgroup\$
    – Andy aka
    Commented Aug 20, 2023 at 12:05
  • \$\begingroup\$ @Andyaka Fixed that typo. Thanks for pointing that out! \$\endgroup\$ Commented Aug 20, 2023 at 12:16
  • \$\begingroup\$ 7 kV does not equal 0.65 kV + 0.05 kV. \$\endgroup\$
    – Andy aka
    Commented Aug 20, 2023 at 12:24
  • \$\begingroup\$ Check under Design Rules > Net Classes. \$\endgroup\$
    – winny
    Commented Aug 20, 2023 at 13:11
  • \$\begingroup\$ You can set the design rules to whatever spacing you want. You may want to do some reading on creepage though, once you're in multiple kilovolts it's common to encapsulate the PCB rather than depend on the (inconsistent and easily damaged) soldermask covered gaps. \$\endgroup\$ Commented Aug 20, 2023 at 14:09

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