The people at iFixit, famous for their detailed hardware tear-downs, have teamed up with Chipworks to show to the average Joe what Apple’s iPhone 4 is hiding underneath a black piece of silicon labeled AGD1 2022 FP6AQ. Unlike other devices out there, the iPhone uses a microscopic, electronic version of a vibrational gyroscope, called a MEMS gyroscope. According to iFixit, the AGD1 2022 FP6AQ chip found inside Apple’s smartphone is a MEMS gyroscope likely designed by STMicroelectronics.
“We partnered with Chipworks to bring you an in-depth look behind the science of these micro-scale gyroscopes”, iFixit reveals on its web site. “Before we get into the nitty gritty of things, let's understand what a gyroscope actually does”, the repair shop says, and proceeds to include a definition found on Wikipedia - "A gyroscope is a device for measuring or maintaining orientation, based on the principles of conservation of angular momentum."
While a mechanical gyroscope uses a spinning rotor in the center to detect changes in orientation, an electronic version of a vibrational gyroscope (a MEMS gyroscope) was the best choice for Apple’s iPhone 4, iFixit suggests. “A basic MEMS device consists of an ASIC and a micro-machined silicon sensor”, the tech-savvy firm explains. “Chipworks has confirmed that the MEMS gyroscope found inside the iPhone 4 is nearly identical to an off-the-shelf STMicroelectronics L3G4200D gyroscope”, it adds.
The teardown explanations reveal that, “When a user rotates the phone, the proof mass gets displaced in the X, Y, and Z directions by Coriolis forces. An ASIC processor senses the proof mass' displacement through capacitor plates located underneath the proof mass, as well as finger capacitors at the edges of the package.” Those interested can visit iFixit here for more information on the iPhone 4 gyro, as well as Chipworks for an even more detailed look at the phone’s inner workings.
It has also been reported that UBM TechInisghts performed its own teardown of the iPhone 4 only to find that Apple may have originally planned to include a gyroscope in the iPad. They reportedly discovered that the Apple tablet also had an empty slot (4mm x 4mm) that would accommodate a gyroscope chip perfectly on its logic board.