Posted: December 23, 2015

Last month we purchased an iPad Pro and an Apple pencil to understand what devices were being used by Apple in this new tablet and stylus solution. This story is not about the iPad Pro, but about the Apple Pencil.

With a physical size of 176 mm long x 9mm in diameter and weighing about 1 gram, we found 15 semiconductor devices. This is quite incredible for something so small. The leading suppliers in the pencil were Texas Instruments and STMicroelectronics. Both companies have four sockets / design wins each. Other companies gaining design wins in the pencil were Maxim Integrated Products, Cambridge Silicon Radio, SiTime, Bosch and Fairchild. 

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.

Chipworks is currently analyzing how the stylus and iPad Pro work together as a system. There seems to be a lot going on from an interaction perspective. The testing still is on-going and we will be writing about our findings in the New Year.