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I am not an electronics engineer. Just working on a project (hobby) that requires me to build a circuit. I just want a timer that turns on an LED after 1 hour. A button will be used to reset the timer which will again turn on the LED in an hour.
I have already made a circuit using a 555 timer IC. For few seconds(19s) of switching, the circuit works fine. I have used this online calculator with C = 0.1mF, R1 = 10kOhm and R2 = 270kOhm. For 3600s, I would either need C=20mF or a very high resistance and equivalent capacitor.
I have been looking online for components but couldn't find any ceramic capacitor of this value. Electrolytic cap are too big in size and I need my circuit to be really small (circle of dia 3cm). I am stuck as there are too many questions now and I dont have the expertise to answer them and can't find much info online
- Should I go for a large capacitor or a large resistance? Or is there another way altogether?
- I cam across SMD components that seem to be very small in size. But their voltage rating is like 30V. Will this work with a 5V supply?
- Is there any other way to achieve this, keeping the circuit as small as possible.