The iPhone 12 may have a hidden ability to reverse charge future Apple products. While the full details are not yet known, it stands to reason that devices with smaller batteries, such as the rumored AirTag or a new generation of AirPods, would be the sort of products that would match well with the potential power supplied. While mostly focusing on safety assessment, a recent Apple FCC filing revealed enough information to suggest possible uses.
Apple’s iPhone 12 has a unique accessory connector called MagSafe that allows cases, mounts and wallets to be attached magnetically. MagSafe is also a charging standard, but it has only been used to charge the iPhone 12 so far, with no mention of reverse charging. MagSafe charging is a wireless charging method similar to Qi charging, but the MagSafe charger supplies 15-watts of power to the iPhone 12, doubling the Qi charging speed. The magnetic alignment also means there is no guesswork involved with this new system. The magnets guide the iPhone 12 to the perfect alignment for the quickest charging possible.
An Apple FCC filing included a description of MagSafe charging of the iPhone 12, but also mentions the ability to wireless charge future Apple accessories with the iPhone. This was first spotted and shared recently by Jeremy Horowitz via Twitter. The FCC filing details that the maximum power delivered would be 5-watts and the operating frequency is 360kHz. Most of the document describes a way to measure Specific Absorption Rate with this new charging method, which is an exposure measurement for determining if a device is safe to use.
Possible iPhone 12 Reverse Charge Uses
Since the 360kHz is not in the Qi charging frequency range, this capability will not be useful for charging existing Apple products that use either MagSafe or Qi standards. In other words, the feature will likely be for future accessories. That could include the rumored AirTag, which is a wireless location beacon, detailed in recent patent applications, though referenced simply as a tag. If the iPhone 12 can charge an AirTag, that would be quite convenient since multiple tags may be in use at once and the need to recharge could be more frequent, especially if used on the body for AR gaming.
The maximum potential power supplied is 5-Watts, so it is unlikely to be useful for charging larger items, such as another iPhone, but topping-off the battery of AirPods could be a possibility. Apple is rumored to be working on new versions of its wireless earbuds, including a second-generation AirPods Pro. Little is known, but rumors persist about an Apple AR headset, another candidate for mobile wireless charging. It would make sense for Apple to withhold this reverse charging capability until it has announced one or more compatible accessories. With another Apple event predicted for November, more details on the company's plans for iPhone 12 reverse charging might come through soon.
Source: Jeremy Horwitz/Twitter, FCC