The Adafruit 24 NeoPixel Ring lets you address every single one of the 24 LEDs and set its 24-bit RGB value. The result is 66mm (2.6in.) in diameter and is the height of bling. These seemingly simple gadgets have triggered an amazing array of creative projects, from watches and compasses to steampunk goggles and more. Each ring has solder pads for 5V DC and Gnd, plus data in and data out. Simply feed the data out from one into the data in of another to control them both from the same microcontroller (MCU).
Since the data protocol has strict timing requirements, the ring is best controlled by a real-time microcontroller such as the Arduino rather than a Linux board like the Raspberry Pi. Use an MCU with a clock speed of 8MHz or greater (Arduino is 16MHz). Adafruit have published a driver library to save you the trouble and let you get on with designing eye catching displays.
Adafruit have a reputation for the quality of their supporting documentation. You will find their Uberguide to NeoPixels and their Best Practices guide invaluable. In particular the Best Practices guide will help you prolong the life of your NeoPixels and help you avoid common mistakes.
24 NeoPixels
24-bits of RGB for each
~18mA per NeoPixel
Can be daisy-chained
*Customers looking to resell on eBay or Amazon should contact Adafruit directly.
