# ARM Cortex-A high efficiency

> ARM Cortex-A processors optimised for low power usage

**Wikidata**: [Q29167086](https://www.wikidata.org/wiki/Q29167086)  
**Source**: https://4ort.xyz/entity/arm-cortex-a-high-efficiency

## Summary
ARM Cortex-A high-efficiency cores are part of Arm Holdings' licensable microprocessor family, optimized for low-power applications. They implement the ARM instruction set and are integrated by chipmakers into system-on-chips (SoCs) for devices like smartphones, tablets, and embedded systems. These cores are sold as intellectual property rather than finished chips, allowing manufacturers to customize them for specific power-efficiency needs.

## Key Facts
- Part of the ARM Cortex-A family, a licensable microprocessor core series from Arm Holdings
- Optimized for low-power usage, targeting high-efficiency applications
- Implements the ARM instruction set and is integrated into SoCs by chipmakers
- Sold as intellectual property (IP) rather than finished chips
- Used in devices such as Android smartphones, tablets, smart TVs, and embedded systems
- Includes cores like Cortex-A5, A7, A53, and A55
- Licensed under different tiers, including POP (optimized physical implementation), standard core, and architecture licenses
- Supports tooling like GCC, LLVM, and Android NDK
- Maintained by Arm Holdings, with no direct fabrication of the cores themselves
- Part of the broader ARM architecture, subclass of semiconductor IP cores and microprocessors
- First appeared in devices like the iPhone 3GS and BeagleBoard
- Supports both 32-bit (ARMv7-A) and 64-bit (ARMv8-A) architectures
- Used in systems requiring energy-efficient computing, such as cloud servers and laptops

## FAQs
### What devices use ARM Cortex-A high-efficiency cores?
ARM Cortex-A high-efficiency cores are integrated into SoCs by manufacturers like Qualcomm, Samsung, and MediaTek, powering Android smartphones, tablets, and embedded systems. They are also used in low-power servers and other energy-efficient computing applications.

### How do ARM Cortex-A high-efficiency cores differ from other ARM Cortex families?
Cortex-A high-efficiency cores are optimized for low-power applications, focusing on energy efficiency rather than raw performance. They are distinct from Cortex-R (real-time systems) and Cortex-M (embedded microcontrollers), which serve different use cases.

### Are ARM Cortex-A high-efficiency cores 32-bit or 64-bit?
Cortex-A high-efficiency cores support both 32-bit (ARMv7-A) and 64-bit (ARMv8-A) architectures, with later models like Cortex-A53 and A55 supporting 64-bit while remaining backward-compatible with 32-bit code.

### Can I buy a standalone ARM Cortex-A high-efficiency processor?
No, ARM delivers synthesizable RTL and documentation, and licensees integrate the core into their own chips, choosing fabrication partners like TSMC or Samsung. You cannot purchase a standalone Cortex-A high-efficiency processor.

### What licensing options are available for ARM Cortex-A high-efficiency cores?
ARM offers three license tiers: POP (optimized physical implementation), standard core (RTL plus testbench), and architecture (rights to design custom cores compatible with the ARM ISA).

## Why It Matters
ARM Cortex-A high-efficiency cores revolutionized mobile computing by providing a low-cost, power-efficient alternative to custom or off-the-shelf CPUs. Before Cortex-A, mobile devices relied on power-hungry CPUs or lacked performance for modern applications. By offering a range of optimized, licensable cores, ARM enabled any semiconductor company to build energy-efficient application processors without the high cost of designing a CPU from scratch. This led to the proliferation of low-cost, high-performance smartphones, reshaped consumer habits, and created the Android ecosystem. Today, Cortex-A cores power everything from Raspberry Pi-class boards to 64-core cloud processors, making them the de-facto standard for energy-efficient compute across all price bands. Their consistent power-efficiency advantage has also enabled fan-less laptops and low-power cloud servers.

## Notable For
- Dominant CPU in mainstream Android smartphones and tablets outside Apple’s custom cores
- First 64-bit licensable core (Cortex-A53, 2012) accelerated the mobile transition to 64-bit
- Pioneered big.LITTLE heterogeneous computing by pairing high-efficiency cores with high-performance ones
- More than 150 billion Arm-based chips shipped, with Cortex-A being the largest share
- Enabled energy-efficient computing in devices like cloud servers and laptops
- Supported by a wide range of development tools, including GCC, LLVM, and Android NDK

## Body
### Product Map
ARM groups Cortex-A into three market slices:
- High-performance: Cortex-A9, A15, A17, A57, A72, A73, A75, A76, A77
- High-efficiency: Cortex-A5, A7, A53, A55
- Ultra-high-efficiency: Cortex-A32, A34, A35

Each core is delivered as synthesizable Verilog or VHDL, allowing licensees to add caches, interconnects, GPUs, NPUs, and radios to create an SoC.

### 32-bit Era
Cortex-A8 (2005) introduced the first superscalar, dual-issue pipeline to the family and appeared in devices like the iPhone 3GS, BeagleBoard, and Palm Pre. Cortex-A9 added multi-core support, powering devices like the Samsung Galaxy S II and PlayStation Vita.

### 64-bit Transition
ARMv8-A, announced in 2011, brought 64-bit registers, larger address space, and a revamped instruction set. Cortex-A53 (little) and A57 (big) formed the first big.LITTLE pairing in 2012, shipping in devices like the Snapdragon 810, Exynos 5433, and Raspberry Pi 3. Successors like A72, A73, A75 refined performance-per-watt, while A76 and A77 pushed laptop-class throughput at smartphone power budgets.

### Licensing Model
ARM offers three license tiers:
1. POP license – optimized physical implementation for a given node
2. Standard core license – RTL plus testbench
3. Architecture license – rights to design custom cores compatible with the ARM ISA (used by companies like Apple, Qualcomm, Nvidia, Microsoft, and Fujitsu)

### Ecosystem
Tooling support spans GCC, LLVM, Arm Development Studio, Linaro, Yocto, Android NDK, and Windows on Arm. Mainline Linux and BSD kernels treat Cortex-A as a first-class citizen, ensuring broad compatibility and support.