led timer circuit

belkin321 · Post by **belkin321** » Sat Sep 27, 2008 2:39 am

I am looking for a timer circuit diagram that would light up 10 leds in a random manner, and the time delay interval could be adjusted....say from 1 to 15 minutes or so. For example, once power is applied, 4 leds would turn on, then a few minutes later a number of other leds would turn on while others turn off. A variable pot. could be adjusted to vary the on/off intervals. Thanks for any assistance.

Sparky · Post by **Sparky** » Fri Oct 03, 2008 1:27 pm

It sounds like you will need a PIC or other micro controller. You will probably use up/down switch or a nob that generates this function (up tick down ticks).

en'til Zog · Post by **en'til Zog** » Fri Oct 03, 2008 7:42 pm

You might try the old standby - the 4060 chip - with the 500K variable resistor. One output can handle 4 low voltage LEDs in SERIES (under 2 volts each, usually RED, ORANGE, YELLOW or GREEN ones).

What colors of LED were you planning on using?

jwrjr · Post by **jwrjr** » Fri Oct 03, 2008 10:32 pm

By using a microcontroller (PIC, AVR, or whatever) you can control which lights turn on and when just by typing some lines of program code.

belkin321 · Post by **belkin321** » Sat Oct 04, 2008 12:19 am

Thanks to all for your help. I wanted to use all white LEDs.

belkin321 · Post by **belkin321** » Sat Oct 04, 2008 12:51 am

Thanks to all for your help. I wanted to use white LEDs. jwrjr, could a 12F683 PIC be used?