I'm creating a simple circuit and I need it to turn on when I press a button and stay on for the time that I choose on the timer (choose the time on a potentiometer, and it needs to go from like a few minutes to 3 hours). Eg. I choose 1 hour, press 'start', the light stays on for an hour and it turns off. The problem is that I can't find a timer that would work that way, can anyone help?

Ps: I don't want to use a microcontroller



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    \$\begingroup\$ There are hundreds of such a timers in your local hardware/lighting store. \$\endgroup\$ – Eugene Sh. Jul 10 '18 at 14:52
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    \$\begingroup\$ Pushbuttons? Hours? Definitely use a microcontroller. \$\endgroup\$ – Spehro Pefhany Jul 10 '18 at 15:22

Like an eggtimer? Most are digital now not pots, well because long analog delays are hard.

But if you want to make one , get a CD4060 and run clock with pot then choose any divider ratio, fixed or tap.

Then use a power FET to drive your load.


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