i've been making a little music gadget recently, which works pretty well apart from an important comparator circuit, or actually two comparator circuits.
I'm finding that whatever I seem to do, I get a little bit of 'chatter' in the transition, which, as I'm feeding an interrupt on a microcontroller, triggers that interrupt twice. I didn't notice it at first as it's *so* slight and I have to zoom right in to see it, but sure enough it's there, on both comparator circuits to a greater or lesser degree.
I also really would like not to have to use this pull-up arrangement, which, if you want to get a really fast transition, is power hungry and really I want this to be as low power consumption as possible. lastly, in the second comparator circuit, i have used a er.. slightly dodgy way of mixing two signals in with each other - the idea is you get a pulse when an incoming wave is either below (for example) 5v or above 5v. because I'm using the coupling cap, the output takes a longer time to charge and I kill my upward transition (which I realise i could re-arrange so the resistor is on the emitter) but this coupling also seems to affect the level of 'chatter' I get.
As you can see I have used hysteresis and filtered the inputs but the chatter remains. What can I do to stop it? Is there a simpler way I can achieve the same goal? I wouldn't have thought this would be such a pain to get right...