iPhone 15 Pro Low-Energy Chip to Allow Solid-State Buttons to Work When Device is Off or Out of Battery

The iPhone 15 Pro and Pro Max will use a new ultra-low energy microprocessor allowing certain features like the new capacitive solid-state buttons to remain functional even when the handset is powered off or the battery has run out, according to a source that shared details on the MacRumors forums.

iPhone 15 Pro Buttons CAD Leak

CAD-based render of new solid-state buttons on iPhone 15 Pro models

The source of this rumor is the same forum member that shared accurate details about the Dynamic Island last year before the iPhone 14 Pro was officially launched, so there is good reason to believe that the following information is reliable.

According to the anonymous source, the new microprocessor will replace Apple's current super-low energy mode that allows an iPhone to be located via Find My after it has been powered off or for up to 24 hours if its battery has been depleted, and enables Apple Pay Express Mode to be used for up to five hours after the battery has run out.

The new chip will allegedly take over these existing Bluetooth LE/Ultra Wideband functions in addition to powering the solid-state buttons – including an "action" button that replaces the mute switch – when the phone is on, off, or the battery is depleted. The microprocessor will "immediately sense capacitive button presses, holds, and even detect their own version of 3D Touch with the new volume up/down button, action button, and power button, while the phone is dead or powered down," says the tipster.

The source also claims that the new low-energy capacitive features are currently being tested with and without Taptic Engine feedback while powered off, but not while the battery is dead, however "whether this tidbit makes it to production or not is highly uncertain but IS being tested," they added.

The source claims that their "man inside" Apple has seen two functional versions of the rumored new unified volume button in testing, including one where the volume goes up/down faster depending on the amount of force used when pressed, and another where the volume can be adjusted by swiping up and down on the button with a finger. They do not know which method will be adopted for the final release, but these features are enabled by software, so this functionality may well be user-customizable.

The anonymous tipster claims that their inside source is on the Apple development team, so they do not have additional information about the design of the new models unless the physical features require software development to complement them.

As per previous rumors, solid-state capacitive buttons are expected to be exclusive to the iPhone 15 Pro models, with the standard iPhone 15 models retaining the same traditional button mechanism as on the iPhone 14 series. The iPhone 15 Pro is also rumored to be gaining a software-customizable button in lieu of the mute switch, with a unified volume button or "rocker" replacing the separate up/down volume buttons. For everything else we know about the new iPhone 15 series, check out our dedicated roundups using the links below.

Related Roundup: iPhone 15
Related Forum: iPhone

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Top Rated Comments

madebybela Avatar
30 months ago
solutions in search of problems
Score: 54 Votes (Like | Disagree)
ersan191 Avatar
30 months ago
Seems like they are running out of things to overengineer at this point.
Score: 34 Votes (Like | Disagree)
Pezimak Avatar
30 months ago
So they’ve replaced some buttons with touch controls and a micro processor and all the other functions and hardware required for all that, just to replace some buttons… and then they’ll apparently increase the price, just to replace some buttons oh and a switch…

Cant innovate anymore my a**…

I’m sure it’ll be a great device and perform very well, but this does seem a bit like change for the sake of change and to warrant you buying a new iPhone does it not?
Score: 28 Votes (Like | Disagree)
saltukkos Avatar
30 months ago
If "action button" will be configurable to perform different actions (or run any shortcut in general), this would be a welcome update.
Score: 26 Votes (Like | Disagree)
MrCrowbar Avatar
30 months ago
Home buttons did fail a lot in earlier iPhones (so people had to use that assistive touch thing because a new home button was pricey). Replacing the physical button with the taptic engine solved that and it also made trackpads on MacBooks infinitely better.

Honestly buttons on iPhones can feel cheap, especially on a $1000+ device. It sucks when they rattle, get a bit stuck from grime or the silent switch not having that satisfying click like on day 1.
Score: 24 Votes (Like | Disagree)
gpat Avatar
30 months ago

i'm more concerned about how this works with cases.
I suppose that most case will just have an open window in those spots. Easy solution.
The Apple official cases will have some kind of special solution that will make them cost x10 as much as the others.
Score: 13 Votes (Like | Disagree)