Ne555

Discussion in 'General Electronics Chat' started by aris, May 6, 2010.

  1. aris

    Thread Starter Member

    May 5, 2010
    45
    0
    Hi,

    Is there any way to trigger with a high input instead of a low an NE555 timer and if yes how could this be done?

    Thanks aris
     
    Last edited: May 6, 2010
  2. mik3

    Senior Member

    Feb 4, 2008
    4,846
    63
    You can use a transistor to invert your trigger signal.

    Connect the emmiter to ground and the collector to Vcc via a 10k resistor. Connect pin 2 of the 555 to the collector of the transistor.
    Also, use a 1k resistor on the base to limit the current through it.

    When you apply a high signal to the base, the transistor will turn on pulling pin 2 to ground ans thus tiggering the 555.
     
    aris and kingdano like this.
  3. Wendy

    Moderator

    Mar 24, 2008
    20,766
    2,536
    [​IMG]
     
    aris and kingdano like this.
Loading...