Non-audio research

So, I'm working on a top-secret project that's non audio related and have a few questions...

I'll get to them in a second, after a little background info.

I need to design a circuit that triggers leds using a pressure sensitive piezoelectric membrane. The leds will stay lit for a finite amount of time and then go out. I'm assuming that would be a job for an off-delay timer.

My first question is, does anyone know of a good forum for this type of stuff? The next is would I be better to look at the analog route, or digital route? I suppose that even if it uses analog components, it's still going to be logic based anyway right?

I think i have my head mostly wrapped around the basics of how i have to do this, but the big thing right now is to get my hands on the membrane and find out what kind of outputs I'm looking at.

Is the amount of required delay also top-secret ?

How accurate must the delay be ?

Smaller delays may be based on the 555 timer, but if you need to go say 10... 15 minutes your cap-value becomes High and leakage will enter so not much accuracy.

Going digital will then be better: clock & counter.


Bye,

Peter

no, the delay time is not secret, haha

I'm thinking in the ballpark of ten seconds

Ten seconds is 555 area, and it doesn't sound like accuracy is a big issue.

OK, film cap, metal film resistor (replacing adjusted trimpot), 555 and back to audio stuff again :wink:

Cheers,

Peter