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Anti vandal led button MOFSET question

  1. Aug 19, 2014 #1
    I'm a total noob when it comes to electronics and you are going to lol at me. Please don't lol too hard.
    Becuase I'm not really good at this stuff its going to be hard for me to explain but Ill do my best.

    I have circuit board for an ecig that I want to use a led anti vandal switch for it like this one http://www.ebay.co.uk/itm/12mm-LED-...n-Switch-/331283052848?_trksid=p2054897.l4275

    So whats the problem ? I only want the led to light up when the button is pressed and go off when the the button is released.

    What I think I need is a MOFSET that can monitor the drain from the battery ??

    As you can see my wiring diagrams if you can even call them that are for children. Ive got this far and now I'm stuck.

    Any help would be much appreciated :)
    Last edited by a moderator: Aug 19, 2014
  2. jcsd
  3. Aug 19, 2014 #2


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    Staff: Mentor

    That's a pretty confusing pushbutton + LED combination. From the e-Bay description, they say they used a 4.2V source and a 470k resistor to light the LED, which makes no sense at all. That's way too big of a resistor.

    And going to the home website for the manufacturer, it looks like you need to specify what voltage you are going to put across the +/- terminals for the LED, which would imply that the current-limiting resistor is already part of the pushbutton housing:


    The lowest LED voltage option they list is 6V, so you probably can't light the LED with just your 3.7V e-cigarette battery.

    The simplest way to light an LED when you press a button to turn on your e-cigarette circuit would be to use a double-pole, single-throw pushbutton, and connect power to an LED through a current-limiting resistor with the second pole of the switch.
  4. Aug 19, 2014 #3
    Thanks for help but I'm lost :)

    This is what was posted in another forum but I don't really understand it.

    I was following the instructions in the qouted text above and got stuck.

    Last edited: Aug 19, 2014
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