Counter with variable delay

Discussion in 'The Projects Forum' started by fuzail, Nov 26, 2010.

  1. fuzail

    Thread Starter New Member

    Oct 3, 2010

    I am trying to make a circuit that will light up an led or some kind of display after a delay.
    So basically,

    * circuit is powered up.
    * circuit waits for specified delay. Then lights up led 1.
    * circuit waits for specified delay. Then led 2 is lit up. Led 1 should be on at all time.
    * continues till maybe around 10 led and then resets.

    The delay i require, i do not know at the moment, because it is tied up to some other parameters of my project
    I have no clue where to begin. i tried to look up such circuits online, but got nothing similar to what i need.
    Can you help me build this circuit ? or point me to somewhere i can get the information on this.
    thank you
  2. Bernard

    AAC Fanatic!

    Aug 7, 2008
    If all delays are the same, start with a 555 astable clock, trailing edge triggers clock input to a 10 bit shift register. the serial in is tied high. LEDs are connected to drivers, ULN something, 7 stage darlingtons to parallel outputs. After initial delay, LED 1 lights up and stays on as each suceeding LED comes on line.