2x 3v coin cell rechargeable with 2 white LED light

Discussion in 'The Projects Forum' started by sanmakk1001, Jul 14, 2014.

  1. sanmakk1001

    Thread Starter New Member

    Jul 13, 2014
    I am planning to build a simple circuit board. As the title said 2x 3v coin cell rechargeable with 2 white LEDs.

    So here is the thing..I am new to circuit designing but I have enough knowledge to build simple circuits. I want to use 2X 3v coin cells with 2 white color LEDS..One socket for charging..Then near the charging slot there will be two tiny LEDS...one green and the other will be red...When the charger is plugged into the socket red LED will turn on..And when the charging will be full GReen LED will turn on..So what components are required to build such circuit. Kindly help me..
  2. wayneh


    Sep 9, 2010
    Get a power socket with an integral switch, and use that switch to control which LED gets power. I'd consider using a 2-color LED if size is a concern.
  3. Bernard

    AAC Fanatic!

    Aug 7, 2008
    What controls the white LED's?
    For charging LED's, a V ref. & 2 comparators, with one set for 1/10 V over fully charged battery to drive red & other at about 75 % of fully charged battery with charger attached.
    Need to know battery chemestry.
  4. wayneh


    Sep 9, 2010
    Oops, I missed the need for a change in the light based on charging status. For that you need at least a comparator. But charging to a set voltage is not the best strategy for all chemistries, as Bernard is noting.