I'm designing a PCB that receives 3 power inputs 3.3v, 5v and 12v.
I need simple way to switch all of them of in one go.

Here is a schematic of my PCB PCB schematic

I looked into using a relay but all the types I found are either to big or don't have the correct specification i'm pretty sure i'm missing something about the correct usage .
I looked for a regular switch but I cant seem to find one that fits my needs.

My 12V line is for running a led strip and may go up to 10A.
The 5V line is just for the level shifter.
The 3.3V is for running a NodeMCU ESP-12E board.

I'm using this to drive everything EVGA SuperNOVA 650 G1+.
I can switch the outside power source but it should run a couple of this boards and I want to be able to Independently shut them off.
I need to run a lot of those and I'm already running 7A on the 12v line so I can't just keep drawing power form only the 12v line there is the matter of the cable and how much amp it can run.
I can use what ever components I want I just need to keep it small.
On the matter of transposing the connectors the board is going to sit in a casing that is labeled and right know it's for a private project so there is no problem.

  • 1
    \$\begingroup\$ Just take one power source (i.e. 12V) and use it to power 5V and 3.3V with step-down converters. Than you only need one switch. \$\endgroup\$ Feb 28, 2019 at 7:09
  • \$\begingroup\$ @Electric_90 I should have mentioned that is not an option. I can't and I don't want to use step-down converters. \$\endgroup\$
    – Rxzlion
    Feb 28, 2019 at 7:26
  • \$\begingroup\$ neither linear regulators? eg 78XY? \$\endgroup\$
    – thece
    Feb 28, 2019 at 8:16
  • 1
    \$\begingroup\$ @Rxzlion - Welcome :-) It would help if you explain more background / context to your question. Please edit your question to explain: (a) What is supplying those 3 voltages to your PCB? (b) Why must you switch them off on your PCB, instead of switching off that external power source? (c) Why are you using an external power source with 3 voltages, instead of generating voltages on your board? (d) What components can you use? (e) On a different topic, you show the same connector part number for J1 and J2, but they have different voltages on their pins. What about the risk of transposing them? \$\endgroup\$
    – SamGibson
    Feb 28, 2019 at 14:52
  • \$\begingroup\$ @SamGibson See my edit. \$\endgroup\$
    – Rxzlion
    Feb 28, 2019 at 16:22

1 Answer 1


You can use 3 PMOS switch all controlled from a single signal (switch or whatever).

enter image description here


  • \$\begingroup\$ I'm looking in to this it looks like what I need but there are many variables for using pmos. Thanks for the guide in the right direction I will update here when i'm done researching this. \$\endgroup\$
    – Rxzlion
    Feb 28, 2019 at 16:27

This site is temporarily in read-only mode and not accepting new answers.

Not the answer you're looking for? Browse other questions tagged .