hello
I want to built a circuit that when ever I start it - it will work for 10 min~
(I want to set the time alone , so if tomorrow I want to change the time to 5 min - I will have to change only the R and C).
the sensor output is "1" at work and "0" at normal state (no move\no sound...)
sensor-->timer-->circuit

I have read about this IC - ICM7250 ,but I didn't understand how do I calculate the time ?
and also how does it now to stop after 10 units of 1 min?

if someone have a better idea I will happy to hear

Thanks ,

 

How repeatable do you want the time interval (10min+-X% on any given interval setting)?
How accurate do you want a "dial" which allows time interval setting?
What are you switching at the output (relay, lamp, LED, motor)?


Have you seen these?