A Nintendo Wii remote has two main jobs. One is to detect your input. The other is to send and receive information to and from the Wii console.

Buttons are one source of input. The Wii remote’s buttons are all digital. When you press them, they’re on, and when you let go, they’re off. When you press a button, it presses against a flexible dome underneath. The dome’s hard core presses against a small metal dome or a contact point directly on the printed circuit board (PCB). When you let go, the flexible dome springs back into shape, and the button pops back out. The remote’s circuitry keeps track of which buttons you press.

Another source of input is the remote’s accelerometer. This is a tiny chip that detects movement. The accelerometer lets you play games by swinging, shaking, turning or spinning the remote.

The remote processes your input and sends it to the Wii console using radio waves from a Bluetooth chip. It also uses an infrared sensor to detect light that comes from a separate sensor bar. This light is like a homing signal. It helps the constantly moving Wii remote keep track of where it is in space. This lets the remote send accurate information about your movements to the console’s Bluetooth receiver.

Printed circuit board

The remote communicates with you as well. A small speaker plays sounds, and a motor can shake the controller. Four small light-emitting diodes (LEDs) on the PCB can also light up. A piece of translucent plastic carries this light to the front of the remote so you can see it.

Flexible domes

To do all this, the remote needs electricity. A set of contacts carries battery power to a small power supply on the PCB. The power supply routes the electricity to the parts of the remote that need it. It can also direct power to the accessories that plug in to the remote.

Contact points