Switch to toggle red/green bicolor leds

Discussion in 'FAQs' started by patgin, Sep 13, 2007.

  1. patgin

    patgin Member


    I would like to make some simple signal for my layout. I would use bicolor leds (green/red) connected in series.
    I have 2 questions. Fisrt, if I connect the first led to make it bright red , can I connect the second to bright green , in the same series?
    And second, I would like to know if they are some switches that simply reverse the current to make the red one became green and the green one became red?
  2. CowDung

    CowDung New Member

    It shouldn't be a problem putting them in series in opposite directions. When current passes through the first, it will light red. When current passes through the second, it will light green. Make sure you use a current limiting resister in your circuit.

    A DPDT switch can be used to reverse the current.
  3. ezdays

    ezdays Out AZ way

    That depends on the LED. Some bi-coloreds have three pins, common cathode or common anode. Those you cannot put in series for obvious reasons.
  4. CowDung

    CowDung New Member

    A very good point...
  5. Pitchwife

    Pitchwife Dreamer

    Hi Patrick. Welcome to the Gauge. :wave:

    To answer your question I have attached a diagram that (hopefully) will help you.

    These are the two types of dual color diodes you will run into. the one on the left will only have two leads coming out of it. You will need a double pole double throw switch and a limiting resistor. The diagram is pretty self explanatory. The diagram below it shows how you would wire the DPDT switch.
    The one on the right will have three leads coming out of it. Refer to the package to determine which lead is which. There is a way to tell by looking at the LED, but I'm afraid that if I tried to explain it I would get my thumbs tied together. :mrgreen:

    Hope this helps.

    ps: just noticed that I got some of my As & Ds and whatnot mixed up, but you get the idea. :oops:

    Attached Files:

  6. Ralph

    Ralph Remember...it's for fun!

    I'm interested in this idea too. What were you thinking of using as a power source Patrick?

Share This Page