The Apple A9X is a
64-bit
In computer architecture, 64-bit Integer (computer science), integers, memory addresses, or other Data (computing), data units are those that are 64 bits wide. Also, 64-bit central processing unit, CPUs and arithmetic logic unit, ALUs are those ...
ARM architecture-based system on a chip
A system on a chip or system-on-chip (SoC ; pl. ''SoCs'' ) is an integrated circuit that integrates most or all components of a computer or other electronic system. These components almost always include a central processing unit (CPU), memory ...
(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 b ...
It first appeared in the
iPad Pro
The iPad Pro is a premium model of Apple's iPad tablet computer. It runs iPadOS, a tablet-optimized version of the iOS operating system.
The original iPad Pro was introduced in September 2015, and ran iOS 9. The second-generation iPad Pro ...
, which was announced on September 9, 2015 and was released on November 11, 2015.
The A9X has the M9
motion coprocessor embedded in it, something not seen in previous chip generations. It is a variant of the
A9 and Apple claims that it has 80% more CPU performance and twice the GPU performance of its predecessor, the
A8X.
Design
The A9X features an Apple-designed 64-bit ARMv8-A dual-core CPU called "Twister".
It offers double the memory bandwidth and double the storage performance of the
Apple A8X
The Apple A8X is a 64-bit ARM-based system on a chip (SoC) designed by Apple Inc. and manufactured by TSMC. It first appeared in the iPad Air 2 and only is used in the iPad Air 2, which was announced on October 16, 2014. It is a variant of the ...
.
Unlike the
A9, the A9X does not contain an
L3 cache
A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which ...
due to its significant
DRAM bandwidth. The A9X is paired with 4 GB of
LPDDR4
Low-Power Double Data Rate (LPDDR), also known as LPDDR SDRAM, is a type of synchronous dynamic random-access memory that consumes less power and is targeted for mobile computers and devices such as mobile phones. Older variants are also known as ...
memory in the 12.9" iPad Pro and 2 GB of LPDDR4 memory in the 9.7" iPad Pro with a total bandwidth of 51.2 GB/s. This high bandwidth is necessary to feed the SoC's custom 12-core
PowerVR Series7XT GPU.
The RAM is not included in the A9X package unlike its sibling, the
A9.
The A9X uses the same NAND interface as the A9, which uses an Apple-designed
NVMe
NVM Express (NVMe) or Non-Volatile Memory Host Controller Interface Specification (NVMHCIS) is an open, logical-device interface specification for accessing a computer's non-volatile storage media usually attached via PCI Express (PCIe) bus. The ...
-based controller that communicates over a
PCIe
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common mo ...
connection.
The iPad Pro's NAND design is more akin to a PC-class
SSD
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is ...
than embedded flash memory common on mobile devices. This gives the iPad Pro a significant storage performance advantage over competitors which often use
mSATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
or
eMMC
The MultiMediaCard, officially abbreviated as MMC, is a memory card standard used for solid-state storage. Unveiled in 1997 by SanDisk and Siemens, MMC is based on a surface-contact low pin-count serial interface using a single memory stack subs ...
to connect to their storage systems.
The A9X 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
HEVC
High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard designed as part of the MPEG-H project as a successor to the widely used Advanced Video Coding (AVC, H.264, or MPEG-4 Part 10). In compari ...
, 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 JPE ...
.
Products that include the Apple A9X
*
iPad Pro 9.7-inch (2016)
*
iPad Pro 12.9-inch (2015)
See also
*
Apple silicon
Apple silicon is a series of system on a chip (SoC) and system in a package (SiP) processors designed by Apple Inc., mainly using the ARM architecture. It is the basis of most new Mac computers as well as iPhone, iPad, iPod Touch, Apple TV, a ...
, the range of ARM-based processors designed by Apple.
*
Apple motion coprocessors
The Apple M-series coprocessors are motion coprocessors used by Apple Inc. in their mobile devices. First released in 2013, their function is to collect sensor data from integrated accelerometers, gyroscopes and compasses and offload the collect ...
*
Comparison of ARMv8-A cores
This is a comparison of processors based on the ARM family of instruction sets designed by ARM Holdings and 3rd parties, sorted by version of the ARM instruction set, release and name.
ARMv6
ARMv7-A
This is a table comparing central proc ...
References
{{Application ARM-based chips
Computer-related introductions in 2015
Apple silicon