[sdiy] Minimum parts count switch de-bouncer.

[Dave Kendall]

Hi Harry.

>There should be a small resistor in series with the
>switch, to limit that peak current. Just assume the
>cap
>is a short, and Ohms' Law will tell you the peak
>current.

Ah, thanks for that...

So, the circuit below would give a positive going pulse drawing 7.5mA for
about 10ms on a single button push.?

I = V(15) divided by (R)10,000 + 10,000
 = 0.00075A

That seems too easy - does the Cap affect that equation. (I bet it does...)

Maybe 1uF is too high. Would it be better to use 100nF and 100K to get 10ms?
                   
                   
                    I----------------I>o------------o  -I
                    I           schmitt trigger
 GND                I
 I     sw           I   I------I 10KI-------I
 I    ____          I   I                   I
 I----o  o---I 10K I ---I                   I
                        I             +     I
                        I------II 1uF II----I----+15V


Sorry if all this is a bit low level, but I've always been crap at theory
and maths.
It's all helping to bring a MIDI synced clock/envelope a bit closer to
reality.

Hopefully other newbies are learning as much as me too...
 
cheers,

Dave (standing on the shoulders of giants, and asking WAY too many
questions... :-)