Apple may switch A17 production to a cheaper 3nm process next year

The iPhone 15 Pro this year is going to be powered by the new A17 system-on-chip, which should be the first large-scale consumer chip in the world to be made on a 3nm N3B manufacturing process. That means a lot more logic and cache in the same size chip, and better power efficiency at the same performance level as current 5nm iPhone chips. We expect big things from the A17.

A new rumor from a Weibo user proclaiming to be an experienced integrated circuits developer suggests that Apple is going to switch production of the A17 at some time next year from TSMC’s N3B process to the upcoming N3E process. The N5E process is estimated to have better costs but may be less efficient than N3B (also known as just N3, the initial “baseline” 3nm process).

The accuracy of this person cannot be verified–they don’t have a long history of accurate leaks, only really gaining prominence by being the first to claim that the USB-C port in iPhone 15 phones will use cables with Apple-supplied authentication chips (like Lightning connectors do) to enable full functionality. That rumor has not yet been verified either, though it has been reported by other sources.

Regardless, this rumor makes sense–and if it’s true, it shouldn’t concern potential iPhone 15 buyers. Here’s why.

First, N3B (aka N3) is the baseline 3nm node. It’s expensive and has relatively poor yields, and the entire supply (or nearly so) is being used by Apple. N3E is the newer, refined version of the 3nm process made with six fewer EUV (extreme ultraviolet) layers and therefore much less expensive to manufacture.

Is N3E less efficient? Yes and no. Anandtech has a good breakdown of these initial 3nm process technologies from TSMC’s public disclosures. Essentially, the newer N3E process will squeeze a little less logic or cache into the same area as N3, but it is expected to actually use a little bit less power and support slightly higher clock speeds. In other words, according to TSMC’s disclosures, N3E is ever-so-slightly less efficient in one metric (density) and just a touch more efficient in others (power, clock speeds).

What does this all mean for the iPhone 15 Pro or future iPhone 16? Not much. If Apple starts producing A17 chips on this new N3E node next year, it’s not going to be very different from the early A17 chips made on the N3 (N3B) node. It might have to be a tiny bit larger and it might use the slightest bit less power, but your experience using the finished product isn’t going to differ. We might not even know when or if Apple changes processes.

The performance of your iPhone comes down to so many factors, including the RAM technology, storage performance, wireless networking, and of course software. Battery life is heavily affected by the display, wireless radios, RAM, and more. If some new-version A17 next year is just a few percent different from the initial version–and that’s a very big “if”–you’ll never even notice.