What’s inside an Apple Watch?(2)

Apple “Unibody” tradition continued

The fabrication of the enclosure continues the Apple “Unibody” tradition of precision machining from a single block of aluminium. Apple is now extending this design philosophy into a highly miniaturised realm, mating the legacy of precision watchmaking with Apple’s specialised manufacturing practices. As with their previous products, Apple has taken fabrication techniquesonce typically restricted to low-volume manufacturing and prototypingand scaled them into a high-volume production environment.

‘”The encapsulation of the entire printed circuit board assembly into a single monolithic module is especially noteworthy,” Keller said. “Whereas many products might have some form of semi-flexible encapsulant applied to the board for protection, shock and vibration purposes, Apple has effectively created one large IC out of the entire assembly. This encapsulation is done by encasing the board in the same plastic/epoxy material used for conventional ICs. Indeed, many of the devices found inside the assembly are already encapsulated, effectively creating an IC-within-an-IC affair.

“To provide electromagnetic shielding, the encapsulated PCB assembly is further treated with a metalised coating deposited over the surface,” Keller added. “This shielding process is used in place of conventional stamped sheet metal shielding, saving a significant amount of space, as well as cutting down slightly on weight.”

Potential boost for wireless charging

The Apple Watch is equipped with inductive charging technology and is being shipped with a wireless charger, based on Apple’s own proprietary MagSafe charging technology.

“It has been speculated that the Apple Watch could be compatible with the Wireless Power Consortium’s (WPC) Qi wireless charging specification,” said Vicky Yussuff, analyst-power supplies & wireless power for IHS. “AppleInsider recently shared a video which appears to show the Apple Watch MagSafe charger being used to charge the Moto 360 smart watch. This would suggest that Apple’s charger is Qi-compatible.

“Apple has not been announced as a member of the WPC or even a supporter of the consortium, so it is unlikely that they have produced a ‘certified’ Qi product. However, the Qi specification is an open standard meaning it is still possible for Apple to build products which are compatible to the specification. This could be the case with the Apple Watch MagSafe charger,” Yussuff said. “Although it cannot be verified if both the Moto 360 smartwatch and Magsafe wireless charger used in the video were both un-modified ‘off the shelf’ products, this could potentially be another boost for the wireless charging industry looking to increase interoperability.”

The Apple Watch battery appears to be somewhat simpler to replace than the batteries in many other Apple products. As long as the display can be carefully removed, the battery is attached with a simple snap-on connector.