HELP ! Connecting different type LEDs

Discussion in 'General Electronics Chat' started by Xribble, Aug 28, 2010.

  1. Xribble

    Thread Starter New Member

    Aug 28, 2010
    Hi guys,

    I want to connect 2 red LEDs and 2 white LEDs to the same powersource.
    This will be going on a Tamiya remote controlled electric buggy.

    I know that if you have two different mA going through the circuit only one set of two will light cause the electricity will take the easiest route through.

    so.... 2 white leds @3.3V with a 9V supply will require a ≈ 150-180 Ω resistor.

    and..... 2 red leds @2V with a 9 V supply will require a ≈ 390 Ω resistor

    Can I plug all 4 leds to the same circuit and use two 9V batteries ? Or can you guys be kind enough as to tell what would be the easiest way to proceed please?

    Thank you in advance,
  2. BMorse

    AAC Fanatic!

    Sep 26, 2009
    You will have to connect both White in series with their own resistor and the reds in series with their own resistor.....


    And I believe your resistor values may be wrong.... what is the forward current and forward voltage on those LED's you are using??

    If you know this info use this calculator to calculate the resistors needed and at what wattage >>

    B. Morse
  3. Xribble

    Thread Starter New Member

    Aug 28, 2010
    Thank you for your reply I figured out how to do it on the internet and I plugged all of them in parallel, one resistor for the most powerful ones and another smaller resistor for the last red led and it lights up very bright and I didn`t burn them.....

    Thanks guys!
  4. Wendy


    Mar 24, 2008