Nanotech - The Circuits Blog

Updated on June 19 at 12:15 p.m. PDT: adding Apple processor discussion in addition to earlier iFixit photo update.

What makes the iPhone 3G S tick, and why is it the "fastest iPhone ever"? Rapid Repair and iFixit tear down the iPhone in Paris and London, respectively, providing some clues.

First, a quick glance at Apple's claims for the iPhone 3G S. The ad copy on Apple's Web site claims that it launches applications faster and that Web pages "render in a fraction of the time." Apple doesn't stop there: "Improved performance and updated 3D graphics deliver an incredible gaming experience, too," according to Apple.

Apple iPhone 3G S disassembled

(Credit: Rapid Repair)

Rapid Repair said Thursday night that the 3G S uses a 600MHz Samsung processor based on the ARM Cortex A8 design. The iPhone also integrates a PowerVR SGX graphics chip from Imagination Technologies, according to Rapid Repair.

This, not surprisingly, beats the iPhone 3G (sans "S"), which uses an older ARM design--that runs at about 400MHz--and a prior-generation graphics chip.

The iFixit team also has done a teardown of the iPhone 3G S, with further analysis to follow.

Though the markings on the main Apple processor do not readily identify the chip, both Rapid Repair and iFixit say it is the Samsung S5PC100. Both sites confirmed this in response to e-mail queries.

The "Samsung ARM Cortex A8-based S5PC100 Mobile Application Processor...adopts a 32-bit ARM Cortex A8 RISC microprocessor and a 64/32-bit internal bus architecture, and operates up to 833MHz," according to documentation on Samsung's site.

The chip is also capable of high-definition (HD) 720p video, Samsung states.

iPhone 3G S main circuit board with Apple-branded processor

(Credit: iFixit)

CNET Reviews has validated Apple's speed claims, saying "for most native applications that don't depend on a cellular or Wi-Fi connection, the iPhone 3G S was consistently faster."

The review continues: "The iPhone 3G S opened the iPod player almost 5 seconds faster, and it was much quicker at loading some notoriously slow apps. For example, Bejewled 2, which can take up to 12 seconds to load on the iPhone 3G, started in just 5 seconds on the 3G S."

And: "The iPhone 3G S also started up much quicker than the iPhone 3G--we were up and running in 26 seconds instead of 50 seconds."

The Palm Pre also uses a Cortex A8 application processor from ARM and the PowerVR SGX graphics from Imagination.

ARM, the company that designs chips for the world's smartphones, said handset makers will deliver the first models using more than one processor core next year, as high-end mobile phones begin to mimic the hardware attributes of PCs.

Palm Pre

(Credit: Palm )

And that means top smartphone suppliers such as Apple and Palm, which both use ARM-based processors, will likely deliver models packing at least two cores inside the main processor--referred to as an application (or applications) processor.

This is a natural progression for high-end smartphones like the iPhone and Palm Pre as the software those phones run gets increasingly sophisticated.

"You'll definitely see handsets shipping with a dual-core A9 in 2010," James Bruce, wireless segment manager for ARM, said in a phone interview earlier this week, referring to the next-generation Cortex-A9 processor from ARM.

The Palm Pre uses a processor based on the current-generation Cortex A8. The iPhone also uses an Apple-branded chip that is based on an ARM design.

"The A8 is just a single core while the A9 will be dual-core, all the way up to quad-core to give smartphones an even bigger performance boost," Bruce said.

He said the move to dual-core phones should happen relatively quickly. "It's very aggressive. It's only going to be in a year's time that you're going to get these phones," he said.

And what about power consumption, a critical concern for smartphones looking to deliver all-day battery life? "What we've done on the A9 is actually make it more power efficient than the A8. The dual-core A9 will be coming out on 45-nanometer rather than the (current) 65-nanometer process," Bruce said. Generally, the smaller the geometries, the faster and more power-efficient the processor is.

Bruce continued. "With the dual-core running at maximum load there's probably going to be an increase of about 10 to 20 percent in power consumption but in general day to day use you're actually going to see better battery life."

So, where does the Apple iPhone 3G S get its claimed "2x faster" leap in speed? Rumors are rampant that Apple is using a new chip to crank up the performance.

Why rumors when Apple has already announced the iPhone 3G S? Apple doesn't disclose chip-level hardware specifications. Moreover, Apple clearly wants to convince any prospective buyer than it's not the iPhone's individual parts that matter but the Apple-branded whole.

Apple claims a speed jump up to two times faster than the previous iPhone: a lot of that may be due to the new processor.

(Credit: Apple)

The fact is no one will know for sure until teardown specialists like iFixit and iSuppli actually disassemble the iPhone 3G S. "Until we actually decap those chips, we won't know exactly which chip it is," according to Francis Sideco, senior analyst for wireless communications at iSuppli.

Kyle Wiens, one of the founders of iFixit, said Wednesday he is flying to Europe to get his hands on the iPhone 3G S and take it apart.

So, what does Apple claim exactly? Here's the Apple ad copy on its Web site. "The Fastest iPhone Ever. The first thing you'll notice about iPhone 3G S is how quickly you can launch applications. Web pages render in a fraction of the time, and you can view e-mail attachments faster. Improved performance and updated 3D graphics deliver an incredible gaming experience, too. In fact, everything you do on iPhone 3G S is up to two times faster and more responsive than iPhone 3G."

Technology Web site Anandtech claimed Wednesday that it knows what the chip is. "Although unannounced, the iPhone 3GS uses (again) a Samsung (system-on-a-chip) but this time...it's got a Cortex A8 and PowerVR SGX; just like the (Palm) Pre," according to an analysis published Wednesday at Anandtech by Anand Shimpi, editor in chief .

Most smartphones today--including the previous versions of the iPhone--are based on some version of an application processor design from U.K.-based ARM. The Cortex A8 is a newer, faster version of the ARM design.

A T-Mobile Netherlands' Web page has published features that specify "256 RAM" and "600 MHz-processor." The link is cited in a report published Wednesday by AppleInsider.

"My gut tells me the Cortex A8 is very possible," said IFixit's Wiens, responding to an e-mail query. Though he emphasized that he is simply guessing. iSuppli's Sideco said that the 600MHz speed cited on the T-Mobile Web site doesn't necessarily mean that Apple is using the latest and greatest ARM design. "I wouldn't necessarily make that connection," he said, adding that there are 600MHz ARM processors available based on older designs.

That said, if the Anandtech report is true, this means the iPhone 3G S's application processor--essentially the brain of a smartphone--is similar to the processor used in the Palm Pre. The Texas Instruments' chip in the Pre is also a Cortex-A8 design core from ARM.

Here's what ARM says. The Cortex-A8 processor "is the highest performance, most power-efficient processor available from ARM. With the ability to scale in speed from 600MHz to greater than 1GHz." And using argot probably lost on many readers, it is an in-order, dual-issue, superscalar microprocessor core. Over-simplified translation: it can do more than one thing at a time.

These specifications compare favorably to the processor used in the previous iPhone: an older-generation ARM chip running at 412MHz.

The Palm Pre chip also integrates a Powervr SGX 2D/3D graphics accelerator based on a design from Imagination Technologies. The Anandtech report claims that the iPhone 3G S also uses this graphics silicon.

One of the big mysteries is how much tweaking Apple does to the basic ARM chip design. In one respect, this question is answered very visibly since Apple stamps its brand on the iPhone processor. And for future iPhones, Apple is expected to tap proprietary technology from the recently acquired P.A. Semi. "With their acquisition of PA Semi, the apps (application) processor is the most likely slot to get internalized," according to Sideco, referring to the likelihood that Apple will focus in-house development on the main processor inside the iPhone.

Marion Morales, vice president of IDC's semiconductors research program, said last month in a phone interview that though Apple uses Samsung chips, "when you look at the processor itself, they're designing the processor and using Samsung as a foundry (factory)," he said, underscoring the fact that Apple emphasizes internally developed technology and de-emphasizes external suppliers, even large companies like Intel and Samsung.