'looking for retriggerable 555 monostable circuit'
> I'm looking for a 555-based monostable (one-shot) circuit whose output
> STAY high as long as short negative-going pulses are present at the
> The textbook 555 monostable circuit doesn't do this. I have a spare
> the board to utilize if necessary. Has anyone come across a 555
> that will do this?
Like Dave V says, you want a "missing pulse detector". I use this
circuit right here for a telephone ring detector:
It gives me a nice continuous high pulse for each ring, instead of
having to deal with a bunch of pulses. Just set the time delay to be
longer than the period of the incoming pulses. Note that this circuit
uses a PNP to short the cap out. No base resistor and no current limit
on the cap shorting. I just love living on the edge, don't you? ;-)
More... (looser matching)
- Last day of these posts
- In 2006
, 2007 only
- New search...