Cracking Open: Apple Pencil is powered by amazingly tiny tech

TechRepublic's Bill Detwiler uses a rotary cutter to slice open the stylus and explores the tech that powers the iPad Pro's must-have accessory.

Bill Detwiler
3 min read
Watch this: Cracking Open: Apple Pencil

Your standard No. 2 pencil is made of wood, graphite, a little metal and bit of synthetic rubber. You can buy a whole box of them for a few dollars. The Apple Pencil costs $99, and for that price, it better be filled with pixie dust and unicorns. I decided to crack it open and find out.

Released alongside the iPad Pro, the Apple Pencil let's you draw, take notes, mark up documents, annotate photos and do basically anything you can do with a traditional pencil. It's also an excellent precision input device for the iPad Pro, and makes it easy to select small menu items or finely adjust app controls.

The pencil connects to the iPad Pro via Bluetooth and charges via a Lightning connector, hidden under a magnetic cap. According to Apple, a full charge will last about 12 hours.

Bill Detwiler/TechRepublic

For more information on the iPad Pro and the Apple Pencil, (including real world test from an artist and video editor), check out the full CNET review.

Thanks to a series of internal sensors, the Pencil can detect how hard the tip is pressed against the tablet and the tip's angle as you move it across the screen, allowing you to make light lines, thick lines, and shaded areas.

Included with the Pencil, is a spare tip, as well as a Lightning-to-Lightning adapter that lets you charge the pencil with a regular iPad or iPhone charger.

With all the specs out of the way, let's get cracking.

Cutting into the Apple Pencil

Bill Detwiler/TechRepublic

Before beginning our teardown, I removed the magnetic cap that covers the Lightening connector and unscrewed the tip. I then secured the Pencil in a vice, and tried to loosen the internal components using a heat gun. Unfortunately, this approach only resulted in me pulling off (and breaking) the Lightning connector and slightly warping the white plastic shell. Time to break out the rotary cutter.

Bill Detwiler/TechRepublic

I carefully cut along the length of the Pencil, taking care to only slice through the outer shell and not the internal components. After making two cuts along opposite sides of the shell, I was able to pry them off. And what did I find? A second, internal metal shell. Oh joy. This one was attached with an extremely tiny tri-wing screw and more adhesive. After making a second set of cuts to each side of the metal shell, I pried them off as well. During the process, I also cut loose the tip assembly.

Bill Detwiler/TechRepublic

Finally, I could clearly see the Pencil's internal hardware. The last steps were to remove a thin metal strip that runs along the battery and circuit boards and detach the circuit boards. I left the wireless antenna connected to the battery.

To see more teardown photos, check out the full Cracking Open: Apple Pencil gallery on TechRepublic, CNET's sister site.

What the teardown tells us

So, what did I learn from cracking open the Apple Pencil? Well for starters, this thing is NOT meant to be taken apart. Which is a real shame, because other styluses, like the Pencil from FiftyThree can be disassembled.

Bill Detwiler/TechRepublic

That brings me to my second observation. If the Pencil wasn't designed to be repaired, why use screws (six of them) inside it?

Bill Detwiler/TechRepublic

As for the brains of the Pencil, there's an 32-bit RISC ARM-based Cortex-M3 MCU from ST Micro, a Bluetooth chip from Cambridge Silicon Radio (which is now part of Qualcomm), and at least five other chips with unknown functions. Powering all this is a tiny 3.82 V, 0.329 Wh lithium-ion battery. There's also the antenna and pressure and angle sensors near the tip.

Despite being one of the more destructive teardowns I've done, it was also a lot of fun.

(No pixies or unicorns were harmed in the making of this video. I can't say the same for our Apple Pencil.)