The Apple Pencil, which launched alongside the iPad Pro back in November 2015, has impressed with its accuracy, and unsurprisingly, it needs a lot of hardware inside for this kind of performance. In fact, the Pencil contains 15 semiconductors to control the stylus' interaction with the tablet, orientation, and more.
Chipworks got their hands on a Pencil and took it apart, gathering information about which companies supplied the parts for the stylus.
The tip of the pencil is quite intriguing as we wanted to know how this pencil interacts with the display. We figured that there has to be some semiconductor devices inside it to drive the pencil. Sure enough we have found a device with package marks "8529043 / 343S00008-A1". The 343S number is standard Apple part numbering and doesn't tell us anything. After a little device de-processing we learned that the driver IC inside the tip of the pencil is designed and fabricated by STMicroelectronics. From the layout it looks like we have a high voltage low current driver IC.
A previous teardown by iFixit also went in-depth on the Pencil, noting the tiny, folding logic board on which all of this silicon sits. You can read about Chipworks' progress in delving into the Pencil at the link below.