On Thu, 17 Feb 2005 23:15:16 -0500, "Peter Michelson"
wrote:


"Bill Bowden" wrote in message
roups.com...

There is a "10 stage LED sequencer" at the below address.
You will need to change the 555 oscillator into a
555 "one shot" circuit so you can use a pushbutton.

Thanks for the tip. I have used a 555 timer before, but I don't think I
ever used it as a one shot circuit, so I'd have to look that up.

The 4017 can be used for just 3 LEDs by connecting the
reset line (pin 15) to the 4th output, (pin 7).

Thanks - I think that's exactly the approach that John Fields took in his
schematic (see other posting in this thread).

---
Well, in all fairness, Bill's is better than mine in that he has a
single current limiting resistor as opposed to my three. Since only
one LED will be lit at any given time, there's only a need for one and
it can be connected from the common cathodes of the LEDs to ground.

He's suggested using a 555 to debounce the switch, but my simple RC
may work just as well. Depends on the switch's bounce
characteristics.

--
John Fields