This is the breakout boards for the built in WS2812 RGB LED. The WS2812 is actually an RGB LED with a WS2811 built right into the LED! All the necessary pins are broken out to back SMD pins for easy cascading. Several of these breakouts can be chained together to form a display or an addressable string.
Integrating control circuit and RGB chip
Built-in signal reshaping circuit
Built-in electric rest circuit and power lost reset circuit