I have a need to be able to connect a lead on a circuit to 1 of 5 different other leads. I think it’s obvious how I can accomplish this with jumpers or DIP switches or encoders.

The wrinkle here is that the voltage is somewhat high ~ 30V.

My question is: is there a electrically controlled way to accomplish this? I’ve looked at multiplexers and some other options but once you get into the 30V range these components seem to get too expensive to justify the cost.

What options are available in this situation?

To summarize, a good solution would:

  1. Allow electronic control
  2. Handle ~ 30V @ .5A
  3. Be low cost — If one component handles mapping 1 to 5 lines, I’d need 5 of them on the board; each of 5 lines gets mapped to one of 5 lines.
  • \$\begingroup\$ How much current does this need to handle? And is the current always flowing the same direction or is it bidirectional? \$\endgroup\$ – The Photon Oct 3 '19 at 4:57
  • 2
    \$\begingroup\$ I had a quick look at a jumper datasheet: 94V, 3Amps is that not enough? \$\endgroup\$ – Oldfart Oct 3 '19 at 5:31
  • \$\begingroup\$ if you can switch the low side and can afford to lose volt or so ULN2003 \$\endgroup\$ – Jasen Oct 3 '19 at 6:24
  • \$\begingroup\$ Multi-pole lathing relays in a tree arrangement. Each layer doubles your combinations Double pole, quald pole or octapole. \$\endgroup\$ – KalleMP Oct 3 '19 at 7:18
  • \$\begingroup\$ Updated my question with some details... Current is always going the same direction. I have to switch it on the low side -- I can't change that aspect. \$\endgroup\$ – jsinglet Oct 4 '19 at 1:59

I recommend relays. Each one normally does 2 outputs, so you'll need to chain them.

chained relays (source: http://zone.ni.com/reference/en-XX/help/375472H-01/TOC1.htm)

  • \$\begingroup\$ I worked this out previously but to do this for each line I’d need 12 relays, which just seems like a lot and very expensive on a component level. It would be like 30 bucks just for the relays. \$\endgroup\$ – jsinglet Oct 4 '19 at 2:40
  • \$\begingroup\$ That is, with 3 relays I can connect one channel to one of the other 4 channels. I just need to do this for the other 4 channels as well. \$\endgroup\$ – jsinglet Oct 4 '19 at 2:42

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.