NeoPixel FeatherWing - 4x8 RGB LED Add-on For All Feather Boards
A Feather board without ambition is a Feather board without FeatherWings! This is the NeoPixel FeatherWing, a 4x8 RGB LED Add-on For All Feather Boards! You can connect a FeatherWing on top or bottom of your Feather board and make your Feather board strut like a peacock at a rave.
Put on your sunglasses before staring into these 32 configurable eye-blistering RGB LEDs. Arranged in a 4x8 matrix, each pixel is individually addressable. Only one pin is required to control all the LEDs. On the bottom we have jumpers for the DIN line to any of the I/O pins on a Feather. You can cut the default jumper trace and use any pin you like. (In particular, the default pin for Feather Huzzah ESP8266 must be moved, try pin #15!)
To make it easy to start, the LEDs are by default powered from either the USB power line or Battery power line, whichever is higher. Two Schottky diodes are used to switch between the two. This power arrangement is able to handle 1 Amp of constant current draw and maybe 2A peak, so not a good way to make a flashlight. It's better for colorful effects.
A level-up shifter converts the 3.3V logic of the Feather to the power line voltage. If, say, you need MORE blinky, you can chain these together. For the second Wing, connect the DIN connection to the first Wing's DOUT. Also connect a ground pin together and power with an independant 5V supply to keep from loading the power supply too much.
Our detailed NeoPixel Uberguide has everything you need to use NeoPixels in any shape and size. Including ready-to-go library & example code for the Arduino UNO/Duemilanove/Diecimila, Flora/Micro/Leonardo, Trinket/Gemma, Arduino Due & Arduino Mega/ADK (all versions)