http://www.ladyada.net/products/pixel36mm/
Adafruit has a great tutorial on some square LEDs that I would like to use for a project. I have a regulated 12V 5A power supply that I would like to use. According to the instructions, it says to wire the power to the LEDs separate from the Arduino. My question is, how can I wire these things such that I do not kill either the LEDs or Arduino using a SINGLE power supply? I don't want two plugs hanging off the thing I'm making.
Thanks.
Best Answer
It's a good idea in general to keep the power for your logic and power devices separated. Motors for instance will generate a lot of noise on your power, and to some extent this may pass straight through the voltage regulator, polluting the microcontroller's \$V_{DD}\$.
One way to keep power supplies separated is feed them via a diode from the common power source. Place a buffer capacitor after the diode, sized for the expected load.
If the LEDs are controlled statically this should be less of a problem than for motors.