Wire one push button to 2 PCB's simultaneously

Discussion in 'General Electronics Chat' started by Silvos, Feb 3, 2016.

  1. Silvos

    Thread Starter New Member

    Feb 3, 2016
    Hi All,

    I am new here so I shall add a short introduction before I start my question, I am a 27 year old 3d designer from the Netherlands. My interest lies within 3d design but occasionally I have a more technical project, I am some understanding of hardware electronic components and software (like how to operate a Raspberry Pi).

    My questions is probably very simple, but I did a lot of effort googling for a solution and I could not find anything about it.
    - I have 2PCB's and each has a standard 4-pin push button like shown in the picture below.
    - Now I want to push the buttons simultaneously, First I designed a hardware solution using a case with a big button that when pushed reached both PCB push buttons, however this solution does not work very well. So I was wondering if there is any possibility of wiring the connectors of both PCB's to one new push button which activates an action on both PCB's simultaneously. However I think I would at least need a push button with 8 pin connectors, which I cannot find.

    Any advice is welcome,
  2. ISB123

    Well-Known Member

    May 21, 2014
  3. dl324

    AAC Fanatic!

    Mar 30, 2015
    You could wire the existing switches in parallel so pressing either switch would affect both boards simultaneously. A schematic would make feasibility easier to determine.
  4. Silvos

    Thread Starter New Member

    Feb 3, 2016
    Thanks for your replies,

    Unfortunately I do not have schematics, I do have a picture of the PCB in question, I hope this will help,
  5. tracecom

    AAC Fanatic!

    Apr 16, 2010
    You should also be advised that the switches in the photos you posted do have four mounting legs, but only two electrical connections per switch.
  6. #12


    Nov 30, 2010
    If you're working in DC, a couple of diodes can direct the current or voltage from one switch to each board and keep the boards from interacting with each other.
  7. AnalogKid

    AAC Fanatic!

    Aug 1, 2013
    The switch in your photo is called a Tact switch because you feel a tactile little thump when the mechanism breaks over to make contact. The switch mechanism is SPST - single pole single throw, the most basic kind of switch. In your kind of application, it usually connects a device input pin to either the positive operating voltage (usally the battery voltage, called Vcc) or the system ground, GND, maybe through a resistor. Without probing around on the board with a voltmeter or scope, it is very difficult to predict what the switch circuit actually is. However:

    IF the two boards are identical,
    AND IF they are powered by separate batteries,
    THEN MAYBE you can get away with wiring the two switched together directly.

  8. dl324

    AAC Fanatic!

    Mar 30, 2015
    Doesn't help at all.

    You need to trace the circuitry around the switches and create a schematic. If you're lucky, the switches will be switching ground or power and you can have a common ground between the two boards.