Self Triggering 555 Timer

Discussion in 'General Electronics Chat' started by renzbagaporo, Feb 4, 2014.

  1. renzbagaporo

    Thread Starter New Member

    Feb 4, 2014
    1
    0
    How is it possible to build a 555 Timer circuit, in monostable mode, which triggers itself when its output becomes low?
     
  2. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
    2,500
    380
    hi,
    Why would you want to do that, you could configure the 555 as an Astable for that operation.
    Whats the application.?
    E
     
  3. KJ6EAD

    Senior Member

    Apr 30, 2011
    1,425
    363
    Try a 10k pullup resistor to pin 2 and a 100nF capacitor from pin 2 to pin 3, but as Eric asks "why would you want to?"
     
  4. vrainom

    Member

    Sep 8, 2011
    109
    19
    But with capacitive coupling it wouldn't self start at power up, if that's what op wants maybe he could use something like this:

    [​IMG]

    Is this to get a sync pulse?
     
  5. AfdhalAtiffTan

    Active Member

    Nov 20, 2010
    117
    11
    Somehow it sounds more like an astable.
     
    Last edited: Feb 5, 2014
  6. alfacliff

    Well-Known Member

    Dec 13, 2013
    2,449
    428
    just use the manufacturers suguested circuit for the astable (self triggering) mode.
     
Loading...