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I am attempting to build a led night light that will come on automatically when the lights in the room go off. Does anyone know of an easy way to use a Photocell (276-1657) to make my light come on automatically. I am using a 9 volt battery and six white leds (260-0017). I would really appreciate any help.
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check out the link-it has everything, you just need maybe 2 resistors and a transistor.
Don’t use 9 volt baterry. Try 3 AA cells- cheaper and more stamina
Check out the tutorial on the timer 555 in Google. There are few shematics with it you might find uceful.
You could use a comparator (or an op-amp as a comparator), a POT, and a resistor. It may also need a transistor to give the output to the LEDs more power. Check out “allaboutcircuits” website Vol III, chapter 8 for a more in depth understanding of how a comparator works. Happy tinkering!