Apple processor chiefs talk in detail about A20 Pro design

Apple executives have been talking in detail about the iPhone 18 Pro’s 2nm A20 Pro processor, but also how it was intentionally designed alongside so many other elements to provide greater speed and efficiency.

The A20 Pro processor in the iPhone 18 Pro, iPhone 18 Pro Max, and iPhone Duo is the most capable chip ever in any iPhone. Each generation is of course better than the last, but this is the first to be made to a 2-nanometer design, and the result is a 20% faster CPU and 40% faster GPU.

Apple chiefs, though, say that the 2nm processor is only part of what has been done to make the new iPhones perform better, stay cooler, and be better suited for AI work. Speaking on “The Circuit” podcast, Apple Silicon and product marketing chiefs Tom Boger, Kaiann Drance, and Sri Santhanam also detailed the side-mounted DRAM, the MCM-style packaging, and the increased neural engine count as key to the new processor.

But then even as they get into technical issues, they also step back to talk about how Apple benefits from doing everything itself.

“We’re not a merchant silicon vendor,” said Kaiann Drance, Vice President of iPhone Marketing. “You know, we’re really building the solutions for our own product experiences.”

What that means, according to each of these executives, is that Apple has the benefit of developing Systems on a Chip (SoC) alongside its whole hardware development effort.

“Sometimes when we build a new SoC, people talk about the process technology node, but it’s more than just that,” said Sri Santhanam, vice president of silicon engineering. “We optimise, obviously, with process in mind, but architecture, design, implementation, packaging, the entire system, the vertical stack, really is what makes our SoC shine.”

There was a difference with the 2nm process, though, as Santhanam said that its higher transistor density meant “we had some tailwind”. It let Apple double the neural engine, add extra GPU cores, and extra memory channels.

At the same time, the silicon team has the constraint of working within the physical dimensions of the iPhone and what this means for thermal issues. With the A20 Pro, Drance said that “we were able then to put the chip right on the vapor chamber to allow us to get the best sustained performance throughout.”

As part of the A20 Pro design, there were also heat benefits from moving DRAM from the top of the SOC to the side. This also helped connect it to the vapor chamber cooling system.

That move did, though, “increase the X/Y footprint of the device,” said Santhanam, “but we work closely with our system partners to make sure we could accommodate that in the main logic board design.”

Designing ahead

Naturally none of the Apple executives discussed future products, but they did talk about how they have to keep plans in mind. Drance described it as giving the processor headroom for future use cases in general, but also having to be more specific.

She said that they have to make decisions about, for instance, memory bandwidth, years in advance. That’s to enable technologies such as camera or AI features that they know will be coming, even if they can’t know when.

The speed and performance increase of A20 processor does back up Apple’s claims of benefiting from its long-standing efforts to develop hardware and software together. Moving from Intel to its own Apple Silicon has been key to this, and has shown huge performance benefits on the Mac as well.