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General project discussion / help
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By audrey
I'm way out of my element here, but am the person required to get an exhibit project done for a nonprofit nature center. I need to have three 5-mm LED bulbs (2 red, 1 yellow) turn on when a mini solar panel is exposed to the sun. Apparently not as simple as it sounds.
I'm thinking I need a breadboard and a resistor for each bulb (they aren't next to each other). Then a power supply stick? For each breadboard? 5V/3.3V? And a 6 W solar panel? (9 w is backordered). But this is where I get lost. 5V power supply, 6 W solar panel, 3 LED bulbs.....
Can anyone help me? Do I need two panels? 6w or will 3.5w work?
Any help or direction would be much appreciated.
By Valen
A generic led requires at most 20mA. As they drop 1.8 to 2 volts they use 40mW each.

Let's start at the beginning. What are the specs of those 5mm LED bulbs. Do they only need to light up when there is sunlight? Or must it use a stored power source. Do you really need 6 Watt panels? Or is that just because of what Sparkfun sells. If so, look around for other vendors.