How TSMC Won Back Exclusivity With Apple for the A10 Chip in iPhone 7

tsmc_logo_newLast year, MacRumors covered the potential reasoning for Apple's rumored return to having a single partner for Apple A-series chip production with the A10 after having both Samsung and TSMC produce versions of the Apple A9.

Since then, TSMC confirmed in conference call comments that its chip packaging changes have led to improvements of 20 percent in both speed and packaging thickness and 10 percent in thermal performance. This has a number of implications for future device performance and future foundry partner selection for Apple.

First, it is helpful to understand why InFO-WLP (Integrated Fan-Out Wafer-Level Packing) is such an important development for Apple's mobile processors. Typically, chips as large as CPUs or mobile SoCs have been attached via "flip-chip" methods which attach an array of inputs and outputs to a package substrate via solder bumps, ultimately enabling it to be attached to a printed circuit board (PCB) for device integration.

From the start, this is a compromise, as it would be preferable to attach a silicon die directly to the PCB to minimize height and reduce the lengths of interconnects between components. A number of technical limits in areas such as interconnect pitch, board produceability, and damage due to board warpage typically prevent this direct attachment.

The above problem had previously been circumvented for smaller I/O count components with a similar concept called Fan-In Wafer-Level Packing, where smaller dies are allowed to route their inputs and outputs in an area roughly the same area as the die. TSMC is just one of many companies beginning to enable this concept for larger I/O count devices in such a way that allows high volume, acceptable yields, and an acceptable cost.

tsmc_info_wlp_slide

Slide from 2014 TSMC presentation on InFO-WLP advancements

With this method, the traditional substrate becomes unnecessary, as a silicon wafer serves that purpose with one or more logic dies included. The reduced height of this method and a thinner redistribution layer (RDL) for remapping pins of the die to the PCB means that all interconnects are shorter, which directly enables lower power and better thermal performance. The transistors driving the outputs on this device now drive less metal length, meaning they can save power. Saving power also means performing better thermally, but a more direct connection to the PCB means there is simply less thermal resistance to the PCB, which can pull heat away from the device.

The promised performance improvements are certainly significant. A 20 percent improvement in performance is roughly equivalent to the improvement expected between successive foundry nodes (e.g. the change from 14 nm to 10 nm). With both TSMC and Samsung only offering refined versions of their 16 nm and 14 nm FinFET processes, this means that total performance gains could be in line with the same improvement seen from the A8 to the A9 chip, but driven by packaging improvements rather than a new process.

Of course, every generation can't enjoy this same improvement, but increased power efficiency is critical for mobile devices to be allowed to hit higher peak limits for short durations. In the keynote for the iPhone 6 family of devices, Apple went into detail about how it made a significant effort to ensure the A8 processor did not throttle itself as the A7 had. This was and is an industry-wide problem as mobile SoC makers have raced to provide the highest performing chips. By taking advantage of new packaging from TSMC, Apple gets more relief in this metric, and freedom to go to a higher power dissipation mode for short periods.

a10_logic_board_side

Bare iPhone 7 logic board with space for A10 chip

A long-term advantage of this technology is to enable much faster main memory interfaces to the logic die, largely by widening the interface. Current mobile SoC packages use PoP (package-on-package) techniques which connect the memory dies to the main processor with tiny wires, which is thermally inefficient and not ideal for performance. By using wafer-level packaging, these drawbacks can be reduced for the main memory, while also increasing the number of connections and data that can be moved in a given time.

In the long run, this move will likely be a cost-saver for Apple as it removes the package substrate. However, the co-design of device die and device package explains why multiple partners are not technically feasible for an effort such as this. Companies like TSMC have also labored for years to make this a reality, with the benefits long being understood.

At this point, there is no denying Apple's technical acumen and bandwidth in chip design. The company has developed multiple chips for market in extremely aggressive timeframes with fully custom designs that rival those of Intel for performance per watt. Apple beat its competitors to market for a 64-bit ARM design by over a year, and designed two custom A9 dies in the time that its competitors designed one.

Given Apple's focus on pushing the performance of its silicon, and TSMC's packaging advancements, it makes sense that TSMC has been able to gain sole possession of Apple's chip orders for at least this generation. Looking forward, the InFO-WLP packaging technique marks a significant development not only for TSMC and Apple, but the semiconductor industry as a whole.

Tags: TSMC, A10 chip

Top Rated Comments

(View all)
Avatar
48 months ago
Kudos for these more technical articles of late. Keep them coming!
Score: 37 Votes (Like | Disagree)
Avatar
48 months ago
Steve Jobs would've never attached the silicon die directly to the PCB to minimize height and reduce the lengths of interconnects between components.
Score: 32 Votes (Like | Disagree)
Avatar
48 months ago
Great article. I give it A10/10 ;)
Score: 15 Votes (Like | Disagree)
Avatar
48 months ago
Grins - "1 less apple component needed from Samsung"
Score: 13 Votes (Like | Disagree)
Avatar
48 months ago

DID THEY THANK THE U.S FOR THIS TALENT?

I thank the US every morning when I wake up.....

On a serious note ....what?
Score: 12 Votes (Like | Disagree)
Avatar
48 months ago
I didn't understand much of the article :(:confused:
Score: 10 Votes (Like | Disagree)

Top Stories

Leaker Claims New 13-inch MacBook Pro Coming as Soon as Next Month

Monday April 6, 2020 2:56 am PDT by Tim Hardwick
Apple will announce a new 13-inch MacBook Pro in May with the codename J223, according to a rumor shared by YouTuber and leaker Jon Prosser. Note: it’s a refresh to the current 13” So the bigger 14” display upgrade is a big possibility— Jon Prosser (@jon_prosser) April 4, 2020 Analyst Ming-Chi Kuo has said Apple plans to release new MacBook Pro and MacBook Air models with scissor keyboards ...

iOS 14 Could Offer Home Screen Widgets, Wallpaper Customizations

Saturday April 4, 2020 3:30 pm PDT by Frank McShan
iOS 14 could offer home screen widgets and wallpaper customizations for the first time, according to 9to5Mac and Twitter user DongleBookPro. Apple is reportedly working to implement widgets that can be moved freely around like icons on the iPhone and iPad homescreen for the very first time. The feature is reportedly codenamed "Avocado" and no other details are available. It was also...

'Leaked' Images Allegedly Show iPhone 12 With Smaller Notch, Rear Camera Redesign, and Home Screen Widgets

Tuesday April 7, 2020 4:28 am PDT by Tim Hardwick
Two images shared on social media this morning are currently stoking speculation about possible hardware redesigns coming to the iPhone 12 and the potential introduction of Home screen widgets in iOS 14. Shared by Twitter user Fudge (choco_bit), the images depict a front and rear graphical representation of a smartphone with interface elements on the screen, suggesting it came out of a...

More References to Apple's Upcoming Low-Cost iPhone Appear Online

Monday April 6, 2020 4:38 am PDT by Tim Hardwick
Further references to Apple's upcoming low-cost iPhone have appeared online, one on a Chinese e-commerce website and another on Verizon's smartphone trade-in page. Spotted by tech blog MySmartPrice, Chinese retailer JD.com has published a placeholder for Apple's so-called "iPhone 9" that includes a teaser image of a veiled smartphone, but other than that it lacks any particularly revealing...

The New York Times, IFTTT, Medium, and Other Apps Adopt Sign in With Apple Ahead of June 30 Deadline

Sunday April 5, 2020 7:08 pm PDT by Frank McShan
Apps with sign-in functionality, including The New York Times, IFTTT, Medium, and more, have continued to adopt Apple's secure Sign in with Apple feature ahead of a deadline of June 30. The deadline for these apps to support the feature was recently extended from April 30. Sign in with Apple, first introduced in iOS 13, allows users to create accounts for apps and websites using an Apple ID. ...

Some Users Experiencing System Crashes on macOS 10.15.4, Especially During Large File Transfers

Monday April 6, 2020 8:17 am PDT by Joe Rossignol
A sizeable number of Mac users are experiencing occasional system crashes after updating to macOS Catalina version 10.15.4, released a few weeks ago. The crashing issue appears to be most prominent when users attempt to make large file transfers. In a forum post, SoftRAID described the issue as a bug and said that it is working with Apple engineers on a fix for macOS 10.15.5, or a...

Apple Releases iOS and iPadOS 13.4.1 With Fix for FaceTime Bug

Tuesday April 7, 2020 10:06 am PDT by Juli Clover
Apple today released iOS and iPadOS 13.4.1, minor updates that come two weeks after the release of iOS and iPadOS 13.4, major updates that introduced iCloud Folder Sharing, a new Mail toolbar, trackpad support for the iPad, and more. The iOS and ‌iPadOS‌ 13.4.1 updates are available on all eligible devices over-the-air in the Settings app. To access the updates, go to Settings > General...

Top Stories: Apple Leaks iPhone SE and AirTags, Apple Buys Dark Sky, and More

Saturday April 4, 2020 6:00 am PDT by MacRumors Staff
With the calendar rolling over to April this week, we yet again saw several leaks and rumors, most notably including Apple itself leaking some references to a pair of long-rumored products: a new budget iPhone SE and AirTags item trackers. Subscribe to the MacRumors YouTube channel for more videos. Apple also acquired popular weather app Dark Sky, while Amazon's Prime Video app now allows...

Apple Reportedly Targeting WWDC for Over-Ear Headphones Launch, New 'AirPods X' Later in the Year

Tuesday April 7, 2020 7:00 am PDT by Eric Slivka
Rumors of Apple-branded over-ear headphones have been circulating for quite some time, while more recent rumors have mentioned an "AirPods Pro Lite" that could also be in the works, and Twitter leaker Jon Prosser's recent foray into Apple rumors provides a bit more detail on what we might able to expect for these products. Current Beats Studio3 Wireless and BeatsX On the over-ear side,...

Apple Donating Over 20 Million Masks to Healthcare Professionals, Producing Face Shields With Suppliers

Sunday April 5, 2020 2:51 pm PDT by Joe Rossignol
Apple CEO Tim Cook today shared a video message with an update on the company's response to the ongoing pandemic. Cook said Apple has now sourced over 20 million masks that it is in the process of donating to healthcare professionals around the world. Apple is working with governments to ensure that the masks are donated to the places of greatest need. Cook added that Apple's design,...