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Topic: Workplace Status Lights(aka Stop Lights) (Read 769 times) previous topic - next topic

Henry_Best

A 9v battery will last about 10 minutes!
You'll need a power supply of some sort (wall wart?)

You'll need one transistor for each array (3 in total)

See here for some circuit ideas
http://www.pighixxx.com/abc-english-version/
Card 2 is the one you need.

Chagrin

20 5mm LEDs is a lot of LEDs and would be quite bright if you use modern LEDs; 5 or 9 would seem more appropriate if you're using a frosted lens and can spread the light out a bit. Anywho, you'd assuredly want to use a wall wart to keep your Arduino powered without relying on your USB power, and then the wall wart can also power your LEDs (sourcing power from the Vin pin). A ~12V wall wart would work well so you can put more LEDs in series. LED Wizard will help you figure out the series/parallel wiring and what resistor to use, and Henry already pointed you to the ABC thing for the transistor part.

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