Apple sells two types of cable assemblies that can connect the iPhone and iPod to a TV. One is termed Component and the other Composite. The Component assembly provides a higher quality picture, but it also uses more jacks. Both assemblies retail for $50.
At first glance, the wiring looks complicated for two reasons. First, it is best to provide an external power supply to the portable devices so they don?t drain their batteries. Second, and more importantly, Apple does not support the HDMI standard which can transport video and audio over a single cable. Thus, while both audio and video exit the iPhone and iPod from a single socket the constituent signals must be delivered separately to the TV.
In the Composite assembly video is input to the TV via a single wire and audio enters as a stereo signal via two more wires. The Component assembly inputs the video to the TV with three wires (one for each primary color) and also uses two pins for stereo audio.


Ron