I need to be able to press and hold a down a push button switch and this send a single short pulse to trigger a 555 timer (monostable mode operation). Holding the push button must not keep the trigger input to the timer high. Any suggestions would be very much appreciated.

 

hi Mike,
Use an AC [capacitor] coupled Trigger to the 555 input.
Do you follow OK.?
E
Image is an example.

 

Thanks for the reply and offer of help.

Am I correct in assuming that by including the circuit to the left of the 555 in your circuit diagram...Q1, R3, R4, R5 , D1 and C3 and substituting the rocker switch for V2 will create a short pulse to the trigger input of the 555 when the state of the the rocker switch opens or closes?

Regards

Mike

 

hi,
This is one simple option for the push switch.
E
Chose R1 C2 values to suit your timed period.

http://www.electro-tech-online.com/tools/IC555V2M1.php

 

hi GT,
If the 555 Trig is held low, the Output will be held high while the Trig is held low.

Eric