Delayed one shot using a 555

[payman]

555 delayed one-shot

Hi,

how do I set up a circiut with a 555 chip to produce only one pulse after about 10 seconds?

 

[david.sh]

you can't. you need to use two 555's... or one 556. Set the first one for 10 seconds, and connect it's output to the second 555's trigger via an edge trigger (a small cap with two pull-up resistors on either side).

 

[payman]

So set the length of the pulse for 10 seconds or the length of the delay to 10 seconds for the first one?

 

[david.sh]

first one times for 10 seconds, then set off the second which times for however long the pulse should be, maybe 1 ms