OVERVIEW

What is C1-Nano?

High-Efficiency Core for Always-On AI

C1-Nano is the first Armv9.3-A LITTLE core, purpose-built for ultra-efficient, always-on computing. It delivers a 26% efficiency gain over Arm Cortex-A520 and is designed to support continuous AI workloads such as voice activation, ambient sensing, and lightweight inference in mobile and embedded devices.

 

C1-Nano enables SoC architects and silicon partners to optimize performance-per-milliwatt tradeoffs across cluster configurations. It's ideal for developing low-power, context-aware AI features that enable battery-conscious devices with responsive, intelligent user experiences.

BENEFITS

Most Power-Efficient LITTLE Core for Next-Gen Devices

 +26% Power Efficiency

Compared to Arm Cortex-A520, with significant L3/DRAM traffic reduction.1
  +10% Performance Uplift in Fetch-Bound Workloads

Decoupled predict/fetch pipeline accelerates instruction access. 2
Lowest Area, Highest Efficiency

+5.5% SPECint2017 performance compared to the Arm Cortex-A520 within 2% core area.2
Vector Unit Improvements

Enhanced vector unit with additional forwarding for improved AI workloads.
Advanced Clock Gating

Reduces power under pipeline stalls and low-Instructions per Cycle (IPC) scenarios.

Improved Branch Prediction

Boosts accuracy, reducing stalls and enhancing throughput.

FEATURES

Optimized for Extreme Power Efficiency

  • Instruction Set Architecture (ISA): Armv9.3-A.
  • AI Support: SME2 enabled.
  • Front-End Efficiency: Decoupled predict/fetch pipeline improves performance in fetch-bound workloads.
  • Branch Prediction: Enhanced accuracy with improved L1 I-cache utilization and idle clock gating.
  • Power Optimization: +26% energy efficiency vs Cortex-A520 in low-power tasks.
  • Area Efficiency: +5.5% SPECint2017 performance within 2% area compared to Cortex-A520.
Arm C1 Nano Block Diagram
SPECIFICATIONS

C1-Nano Specifications

C1-Nano is the most power-efficient Armv9.3-A little core to date with a focus on improving power efficiency for client devices. It is built on the foundation of the Arm Cortex-A520 microarchitecture and provides significant power reduction of up to 26% at the lower range of workloads for little core and DSU combined.

Visit Arm Developer for more details.

Key Documentation

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Talk with an Expert

Learn how C1-Nano CPU can provide the balance of power efficiency and performance for improved battery life.

Contact Us

Frequently Asked Questions: C1-Nano CPU

1. What is the C1-Nano designed for?

C1-Nano is built as a high-efficiency Armv9.3-A LITTLE core optimized for always-on AI, voice assistants, and lightweight inference tasks. It targets sustained background processing in mobile and embedded devices with minimal power consumption.

2. How does C1-Nano compare to Arm Cortex-A520?

C1-Nano offers a 26% improvement in power efficiency and up to 5.5% better SPECint2017 performance than Arm Cortex-A520, while maintaining a similar silicon area footprint. This makes it a compelling upgrade for power-sensitive workloads.

3. What architectural enhancements does C1-Nano feature?

Key enhancements include a decoupled predict/fetch pipeline, improved branch prediction, vector unit upgrades with better forwarding, smarter prefetch logic, and advanced clock gating. These optimizations enable faster instruction flow and more efficient AI inferencing.

4. Does C1-Nano support vector operations and AI acceleration?

Yes. C1-Nano includes a refined vector unit with enhanced forwarding and power efficiency, tailored for low-power AI inferencing and parallel workloads common in voice and sensor applications.

5. Where can I find C1-Nano technical documentation?

You can access the C1-Nano Technical Reference Manual , and a Cortex-A processor comparison chart in the “Specifications” section of the product page.

1. Compared to previous generation. Testing done internally, April 1-April 15, 2025; actual results may vary.

2. Compared to previous generation. Testing done internally, Jan 15-March 30, 2025; actual results may vary.