The Apple A8 is a

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit CPUs and ALUs are those that are based on processor registers, address buses, or data buses of that size. A compu ...

ARM-based system on a chip (SoC) designed by

Apple Inc. Apple Inc. is an American multinational technology company headquartered in Cupertino, California, United States. Apple is the largest technology company by revenue (totaling in 2021) and, as of June 2022, is the world's biggest company ...

It first appeared in the

iPhone 6 The iPhone 6 and iPhone 6 Plus are smartphones that were designed and marketed by Apple Inc. They are the eighth generation of the iPhone, succeeding the iPhone 5, iPhone 5C and iPhone 5S, and were announced on September 9, 2014, and rele ...

and iPhone 6 Plus, which were introduced on September 9, 2014. Apple states that it has 25% more CPU performance and 50% more graphics performance while drawing only 50% of the power of its predecessor, the

Apple A7 The Apple A7 is a 64-bit system on a chip (SoC) designed by Apple Inc. It first appeared in the iPhone 5S, which was announced on September 10, 2013, and the iPad Air and iPad Mini 2, which were both announced on October 22, 2013. Apple states ...

. The latest software updates for the 1.1GHz and 1.4GHz variants systems using this chip are iOS 12.5.6, released on August 31, 2022 as they were discontinued with the release of

iOS 13 iOS 13 is the thirteenth major release of the iOS mobile operating system developed by Apple Inc. for their iPhone, iPod Touch, and HomePod lines. The successor to iOS 12 on those devices, it was announced at the company's Worldwide Develop ...

in 2019, and 1.5GHz variant for the

iPad Mini 4 The iPad Mini 4 (stylized and marketed as iPad mini 4) is the fourth-generation iPad Mini tablet computer designed, developed and marketed by Apple Inc. It was announced along with the iPad Pro on September 9, 2015, and released the same day. ...

is iPadOS 15.7.1, released on October 27, 2022 as it was discontinued with the release of

iPadOS 16 iPadOS 16 is the fourth and current major release of the iPadOS operating system developed by Apple for its iPad line of tablet computers. The successor to iPadOS 15, it was announced at the company's Worldwide Developers Conference (WWDC) on ...

in 2022, while updates for the 1.5GHz variant continue for Apple TV HD. The A8 chip was discontinued on October 18, 2022, following the discontinuation of the Apple TV HD.

Design

The A8 is manufactured on a 20 nm process by

TSMC Taiwan Semiconductor Manufacturing Company Limited (TSMC; also called Taiwan Semiconductor) is a Taiwanese multinational semiconductor contract manufacturing and design company. It is the world's most valuable semiconductor company, the world' ...

, which replaced

Samsung The Samsung Group (or simply Samsung) ( ko, 삼성 ) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Town, Seoul, South Korea. It comprises numerous affiliated businesses, most of them united under the ...

as the manufacturer of Apple's mobile device processors. It contains 2 billion transistors. Despite having twice the number of transistors of the A7, the A8's physical size has been reduced by 13% to . The A8 uses LPDDR3-1333 RAM on a 64-bit memory interface; in the iPhone 6/6 Plus, sixth generation iPod Touch, and

HomePod The HomePod is a smart speaker developed by Apple Inc. The HomePod was designed to work with the Apple Music subscription service. The HomePod was announced on June 5, 2017, at the Apple Worldwide Developers Conference. Its launch was later d ...

, the A8 has 1 GB RAM included in the package. Meanwhile, the A8 in the iPad Mini 4 and 4th generation Apple TV is packaged with 2 GB RAM. The A8 CPU has a per-core L1 cache of 64 KB for data and 64 KB for instructions, an L2 cache of 1 MB shared by both CPU cores, and a 4 MB L3 cache that services the entire SoC. As its predecessor, it has a 6 decode, 6 issue, 9 wide, out-of-order design. The processor is dual core, and as used in the iPhone 6 has a frequency of 1.4 GHz, supporting Apple's claim of it being 25% faster than the A7. It also supports the notion of this being a second generation enhanced Cyclone core called Typhoon, and not an entirely new architecture which would supposedly mean a more significant performance gain per Hz. The A8 also integrates a

graphics processing unit A graphics processing unit (GPU) is a specialized electronic circuit designed to manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, m ...

(GPU) which is a 4-shader-cluster PowerVR Series 6XT. However the GPU features custom shader cores designed by Apple. On October 16, 2014, Apple introduced a variant of the A8, the A8X, in the

iPad Air 2 The iPad Air 2 is the second-generation iPad Air tablet computer designed, developed, and marketed by Apple Inc. It was announced on October 16, 2014, alongside the iPad Mini 3, both of which were released on October 22, 2014. The iPad Air 2 ...

. Compared with the A8, the A8X has an enhanced 8-shader-cluster GPU and improved CPU performance due to one extra core and higher frequency. The A8 has video codec encoding support for

H.264 Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distr ...

. It has decoding support for H.264, MPEG‑4, and

Motion JPEG Motion JPEG (M-JPEG or MJPEG) is a video compression format in which each video frame or interlaced field of a digital video sequence is compressed separately as a JPEG image. Originally developed for multimedia PC applications, Motion JPEG ...

Patent litigation

The A8's

branch predictor In computer architecture, a branch predictor is a digital circuit that tries to guess which way a branch (e.g., an if–then–else structure) will go before this is known definitively. The purpose of the branch predictor is to improve the flow ...

has been claimed to infringe on a 1998 patent. On October 14, 2015, a district judge found Apple guilty of infringing U.S. patent , "Table based data speculation circuit for parallel processing computer", on the Apple A7 and A8 processors. The patent is owned by

Wisconsin Alumni Research Foundation The Wisconsin Alumni Research Foundation is the independent nonprofit technology transfer organization serving the University of Wisconsin–Madison and Morgridge Institute for Research. It provides significant research support, granting tens o ...

(WARF), a firm affiliated with the

University of Wisconsin A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, ...

. On July 24, 2017, Apple was ordered to pay WARF $506 million for patent infringement. Apple filed an appellate brief on October 26, 2017, with the

U.S. Court of Appeals for the Federal Circuit The United States Court of Appeals for the Federal Circuit (in case citations, Fed. Cir. or C.A.F.C.) is a United States court of appeals that has special appellate jurisdiction over certain types of specialized cases in the U.S. federal court ...

, that argued that Apple did not infringe on the patent owned by the Wisconsin Alumni Research Foundation. On September 28, 2018, the ruling was overturned on appeal and the award thrown out by the U.S. Federal Circuit Court of Appeals. The patent expired in December 2016.

Products that include the Apple A8

* iPhone 6 & 6 Plus *

iPod Touch (6th generation) The sixth generation iPod Touch (marketed as the iPod touch) is a mobile device designed and marketed by Apple Inc. with a touchscreen-based user interface. It is the successor to the iPod Touch (5th generation), becoming the first major upda ...

* Apple TV HD (formerly 4th generation) *

Gallery

Notes

References