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Battery operated led with 6 hour run time per day. Answered

Trying to figure out how to make a circuit for a LED light that is run by two AA or two C batteries. I would like the light when turned on to run for 6 hours and then turn off. Then autmatically turn on the same time each day and run for 6 hours without having to manually reset the light. Having a hard time trying to figure out how to make this timer. It would also be a bonus if the the led flickered like a candle. Thanks for any help in the right direction.

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Shadowmang

10 years ago

possibly you could just build the led circuit and add one of those light timers for lamps and stuff. Thats how I would do it but I'm not very good at electronics and programming :x

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killerjackalope

10 years ago

Well 2700mah X 2 = 5400mah @2.8V So it would need to be stepped up slightly to make it light the LED but @ 30ma it'd run for 180 hours direct, or have I just been very silly, assuming the circuitry took it up to 100ma you'd be looking at 54 hours of runtime.

As for the circuit used a super simple clock circuit could be used, a 555with a massive capacitor or some kind of counter module, a PIC chip wouldn't need much complicated programming to do both the timing and the candle flicker.

Remembering the stepup necessary to make the LED work a small boost converter or even a clever joule thief circuit could work, actually a joule thief and a camera quality rechargeable could be used as a single battery but you'd need to get the transformer tuned to be running at the right voltage.

hope that helps, some clever person will probably say something deserately simple now.