Before you layout a circuit, it's generally a good idea to understand what is happening in your schematic. And before you lay out a schematic, it's generally a good idea to understand what is happening in your block diagram.
"This book is a bit technical. If you are a beginner, it's okay that you don't understand everything that follows -- your first project will still be successful. Try to pick up as much as you can, and ask questions in the forums!"
8. Addressable RGB LEDs
The Addressable RGB LEDs used in this circuit operate off of 5V power rail and 5V logic. While we could probably get away with running them from 3.3V logic, if there is too much ground bounce and Vcc-sag inside the LEDs, we could run into trouble. So a logic-level converter is created out of an N-channel MOSFET. The circuit has a bypass and bulk capacitor for each LED to help reduce noise with the assumption that the LEDS can be placed far from one another. The 0.1 uF capacitor should be placed as close to the LED as possible, with the 10 uF just on the other side of it.