Counter with variable delay

Thread Starter

fuzail

Joined Oct 3, 2010
2
Hi,

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
 

Bernard

Joined Aug 7, 2008
5,784
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.
 
Top