555 Delay Output Pulse

[ahughes3214]

Hello,

I have been on google for a couple hours and cannot seem to find exactly what I need. I believe I need a monostable (one shot) 555 with delay but cannot find a circuit that meets all my requirements.

1) The 555 circuit would be powered at all times waiting for the push button signal.
2) A momentary pusubutton (normally open) would be pressed connecting +12vdc to a Phidget Digital input "A". I would like to use this same signal to trigger the 555 one shot delay (upon the drop to 0vdc once the pushbutton is released). The length of time the button is pushed is not critical.
3) After the 555 time delay of at least a couple seconds, the 555 output would need to pulse high (3 to 12vdc) to trigger a second Phidget digital input "B".

Any help would be appreciated. Thanks, Andrew

 

[BrownOut]

You need a 556 or two 555's configured as one-shots. The first will be the time delay, and triggers the second, which will pulse your circuit.

 

[dougy83]

Something like this was discussed here: https://www.electro-tech-online.com/threads/more-elegant-solution.111452/#post911684

 

[MikeMl]

This does what you asked for. Note: to show the details of the output pulse, I made the delay shorter by a factor of ~100. To get a ~2.5sec delay, make C1 4.7uF instead of 47nF.