My two key takeaways from Apple’s “California Streaming” new product announcement event, which took place earlier this week, are as follows:
I’m only kidding on the above being the “key” takeaways, although they’re both still notable in their own rights. And considering that some of the sales I’ve seen of late were for products whose successors weren’t announced this week, I’d wager Apple’s got at least one more launch event still sitting in the chamber to discharge before the end of the year. But enough of future prognostications (next-gen AirPods, anyone? Computers with beyond-M1 CPUs inside?), what about the present moment?
A15 Bionic CPU
Common to many of the new products launched on Tuesday is their processing nexus, the A15 Bionic SoC. This one’s a bit of a head-scratcher (although as usual, I have some ideas as to what may be going on). First take a look at this summary slide, shown during the iPhone 13 portion of the program (which I’ll discuss in more depth soon):
The tip-off here that Apple’s “thinking different” is in the performance comparisons. Historically, Apple has pretty much ignored the competition and done comparisons against prior generations of its own products; this time they’ve obviously taken a different tack (and in the process is also notably not directly naming who they’re comparing against). There’s a different path to tackle the comparison challenge, however: here’s a conceptually similar slide from the sixth-generation iPad mini portion of the program (again, hold that thought):
Here, the comparisons are straightforward and versus the fifth-generation iPad mini, which had used the A12 Bionic SoC. Analysts such as Dylan Patel at SemiAnalysis subsequently did the two-step conclusion dance: Patel noted that Apple had previously compared the A12 Bionic against the A14 Bionic found in the latest iPad Air, indicating a 50% CPU performance boost. At least on paper, there seems to be no further CPU improvement in the A14-to-A15 transition.
However…Apple has seemingly advanced the core architectures themselves, no matter that it’s retained the A14’s “2 Big (high performance) + 4 Little (high efficiency)” cluster arrangement. This time the “Big” cores are called “Avalanche” and the “Little” cores are “Blizzard,” whereas with the A14 (and its M1 derivative) they were (respectively) “Firestorm” and “Icestorm.”
Note first that Apple (as usual) never discusses processor clock speeds. Consider this conjecture in the context of Apple’s claims that A15-based iPhones have much longer battery life than their A14-based precursors. Perhaps the A15 does more average work per clock, thereby enabling lower peak clock speeds and leading to equivalent performance at much lower active power (or energy, to be more precise) consumption?
One other possibility, which I first noticed in AnandTech’s liveblog verbiage (giving credit where it’s due) is that the A15 Bionic is Apple’s first SoC to implement Arm’s Armv9 architecture, which was introduced earlier this year. Keep in mind that the terms of Apple’s Arm license still require it to support a particular architecture generation’s full instruction set, although Apple is free to implement that instruction set in silicon however it chooses. If iOS doesn’t yet harness any of Armv9’s advanced matrix arithmetic and other enhancements, any innate architecture improvements won’t be harnessed.
Speaking of matrix arithmetic (and the like), another key means of optimizing the performance-vs-power consumption balancing act, of course, is to offload from the main CPU whatever functions can be cost-effectively instead implemented in dedicated coprocessor circuitry (i.e., implementing heterogeneous computing). For example, the graphics processor, which can more generally be thought of as a massively parallel arithmetic engine, has seemingly been significantly improved in this SoC generation. Commensurate with improvements here, and in order to more efficiently feed the GPU along with other function blocks, the system cache has doubled, to 32 Mbytes.
And speaking of “other function blocks,” although the neural processing unit (NPU) remains 16-core, its claimed performance has increased from 11 TOPS (tera, i.e. trillions of, operations per second) to 15.8 TOPS, although the real-life meaningfulness of this particular metric is debatable. The sum total of these and other enhancements?: Total transistor count has grown from 11.8 billion transistors on the A14 to 15 billion on the A15, with both chips manufactured on the same 5 nm TSMC foundry process. That’s one big die.
One more comment on the A15, specifically its GPU, before moving on to the systems containing both it and other Apple-designed application processors. Much ink has been spilled since Tuesday on the fact that some of the new products (the 6th generation iPad mini, and specifically the two “Pro” variants of the iPhone 13) use versions of the A15 with all five graphics cores functional, while others (specifically the standard iPhone 13 models) run on a four-GPU-core A15. While this may be the first time that Apple’s done such a thing with iPhones (a “thing” which, perhaps obviously, enables Apple to maximize usable A15 yield out of fabrication), it’s not the first time that Apple’s done this at all.
As I mentioned back in October of last year (see “Apple updates for wearables, iPhones, tablets, and more”), for example, Apple put the A12Z in its then-current iPad Pro, versus the previously used A12X; the two chips were identical, just with the full allotment of eight graphics cores enabled on the “Z’ version of the SoC versus only seven on “X.” Sound familiar? And one month later (see “The transition to Apple silicon Arm-based computers”), I pointed out that Apple was using both seven- and eight-GPU core variants of the M1 SoC in its various new Arm-based computers—again, harnessing the exact same sliver of silicon.
I’ve purposefully spent the bulk of the word count of this piece on more technical topics, befitting EDN’s readers’ interests. The discussions of the systems themselves, ordered as they were introduced on Tuesday, will therefore intentionally be more concise:
9th Generation iPad
As I alluded to earlier, when I saw that shipping lead times were increasing on the base model iPad introduced a year ago, I suspected either/both a) Apple was running into component availability constraints (which seemingly would have affected other products, too) and/or b) the company was intentionally phasing out production and transitioning to a newer-generation offering. Seems the latter was the spot-on prediction. Apple has migrated from the A12 Bionic SoC to the A13 Bionic, and the all-important “selfie” front camera has dramatically increased in resolution (from 1.2 Mpixel to 12 Mpixel) and also supports “Center Stage” auto-digital zoom and recentering to keep the subject visible when videoconferencing. The 10.2” display also now supports True Tone automatic brightness and color temperature optimization. But still no 5G cellular option, only legacy LTE.
6th Generation iPad mini
This to me was the most meaningful product line advancement announced on Tuesday. Then again, with a 4th generation iPad mini currently on my night stand next to the bed (which replaced a 2nd generation iPad mini, and, before that, several Android-based models), I’ve obviously long been fond of the small-screen tablet concept. Keep in mind, first and foremost, that generational prices at equivalent capacities and other feature set allotments have raised by 25%. What do you get for that added dough? A five-GPU-core A15, to begin with (is it just me, or is it also wild to you to think that Apple’s tiniest iPad is also its most SoC-advanced?); more RAM; a bezel-free 8.3” Liquid Retina display with True Tone; a chassis reminiscent of an iPhone; Apple Pencil support; optional 5G cellular connectivity; a 12 Mpixel front camera, again with Center Stage support; a transition from Lightning to USB-C connectivity; and four color options.
7th Generation Apple Watch
This one, to me, was conversely the biggest yawner: an evolved chassis and larger display, the latter also more durable, while retaining band backwards-compatibility; 33% faster charging; IPX6 dust resistance; new colors and finishes; and well, that’s about it. With the same CPU and memory as the Series 6, there is no tangible motivation for those owners to upgrade. The biggest surprise to me was that Apple is still also keeping not only the Apple Watch SE but also the geriatric, hard-to-upgrade Apple Watch Series 3 in the product stable.
Coming in both standard and “mini” variants, as with the iPhone 12, this one’s (as previously mentioned) powered by the four-GPU-core variant of the A15 Bionic SoC. Looking again at the detailed spec comparisons, I’m doubling down on my prior comments that by all rights this should have instead been an “iPhone 12S” half-step, as Apple has done several times in the past. So what’s there to “write home about?” A 20% smaller notch in the display to make room for the front camera and other sensors; new colors; larger image sensors for (along with added sensor-shift optical image stabilization) better low-light performance; additional computational photography modes befitting the more advanced NPU powering them; and other camera re-layouts and nips-and-tucks. And, as with the iPhone 12s, both models (as well as the Pro variants I’ll discuss next) support both sub-6 GHz and less common (at least currently) mmWave 5G, the latter albeit US-only from a frequency band standpoint. New is dual-eSIM support.
About that additional battery life: to some degree it’s likely the result of improvements at the SoC and other circuit levels (the A15 Bionic likely also belatedly supports LPDDR5 SDRAM, for example). But to a far greater degree it’s likely also the result of internal layout redesigns that have enabled Apple to squeeze larger, higher capacity batteries inside:
Batteries that are unfortunately therefore also heavier than they were before…leading to heavier phones than before. To wit, what else remains in Apple’s iPhone portfolio? Two LCD-based (and non-5G-supportive) smartphones: the second-generation iPhone SE (sorta) and the iPhone 11. And, at least for now, both the “mini” and standard versions of the iPhone 11. But nothing else, including the long-lived iPhone XR, which has finally been retired.
iPhone 13 Pro
I realize I’m sounding like a broken record, but these two really should have also been named “12S Pro” instead (and supposedly they almost were). They have A15 SoCs with five-core GPUs. As with the iPhone 12 Pros, they move from two rear cameras (wide and ultrawide) to three (with added telephoto), and as with the iPhone 13s, those cameras are re-laid out and have larger sensors and other enhancements, including the ability to capture 4K ProRes video, but only at storage capacities of 256 GBytes and more. Speaking of which, yes the rumors were true: a 1 TByte option is offered for the first time. Last but not least, and again in the “belatedly” bin, the Pro variants’ displays support up to 120 Hz refresh rates, along with variable refresh rates as low as 10 Hz. The prior-generation iPhone 12 Pro models are no more.
The Cutting Room Floor
What didn’t we get? The lengthy some-more-crazy-than-others rumor list includes:
- iPhone satellite connectivity
- Always-on iPhone displays
- A third-generation iPhone SE
- New AirPods
- New computers
I’m guessing that those last two are a matter of when, not if, and specifically soon. If I’m right, you’ll undoubtedly be hearing from me again soon, too. Until then, let me and your fellow readers know your thoughts on this week’s Apple news in the comments.
—Brian Dipert is Editor-in-Chief of the Embedded Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.