ulra bright, variable speed, LED strobe running on 12V batt

Discussion in 'The Projects Forum' started by cock_e, Jan 22, 2013.

  1. cock_e

    Thread Starter New Member

    Jan 18, 2013
    Hi there everybody.
    Recently joined forum, not so skilled in electronics, just understanding basics :rolleyes:

    My brother in law asked me if I could build him a LED strobe that he can put on his outdoor bag pack (don't know reasons why...some tracking purpose...I suppose).
    So, I've searched all around WWWeb and didn't find any scheme for 12V ultra bright LED strobe, that can vary it's speed - but regarding the temperature/current curve of the LEDs.
    I plan to use Luxon 3080-3400mcd (2.8-3.6V) green/blue 5mm leds (cause alredy have those :) ).
    Basically it's about driving apm valued currents for mili seconds period...
    that type of gadget.

    Any suggestions, links, guidelines, old posts - I'll really appreciate it!
  2. wayneh


    Sep 9, 2010
    There are many commercial products that do exactly what you described. Or at least very close. Do you really want to build something? It will cost you more in time and money.

    The circuit you would need is a variable frequency timer and most DIYers would use a 555-timer based circuit for this, perhaps with the timer controlling a MOSFET that switches the current through the LEDs. You need to control the current thru the LED, to at least limit it to a safe value. You could also have some control of the duty cycle, so the LED would be on maybe 5-10% of the time, for energy savings.
  3. sheldons

    Well-Known Member

    Oct 26, 2011
    heres a simple circuit you can try -use hi brightness leds for best results...
    absf likes this.
  4. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    For an LED to look like a "Strobe", on duration of 50mS to 100mS (1/10th second), followed by a 1 second or more period of off time looks good, and saves a lot on battery power.

    What is the capacity of the 12V source in the backpack? Wouldn't AA Batteries be simpler and lighter?