iFixIt has gone through the difficult process of tearing down the new Apple Magic Trackpad. The site notes that "this is not for the faint of heart. A copious amount of heat, guitar picks, and plastic opening tools were required to make this thing budge."
● At the heart of the Magic Trackpad's logic board lies a Broadcom BCM2042 for Bluetooth connectivity. This is the same chip used by the Magic Mouse for data transmission.
● A Broadcom BCM5974 touch screen controller chip provides Multi-touch functionality. This is the same chip you'll find in the iPhone, iPod Touch, and MacBook Air.
Hit the link below for their entire teardown analysis.