SiFive Intelligence

SiFive Intelligence X280

The SiFive Intelligence™ X280 is a multi-core capable RISC-V processor with vector extensions and SiFive Intelligence Extensions and is optimized for AI/ML compute at the edge.

In addition to ML inferencing, it is ideal for applications requiring high-throughput, single-thread performance while under power constraints (e.g., AR, VR, sensor hubs, IVI systems, IP cameras, digital cameras, gaming devices).

Download X280 and X280-MC Data Sheet >

SiFive Intelligence X280 Key Features
  • SiFive Intelligence Extensions for ML workloads
    • Custom instructions to greatly accelerate Neural Network computation
    • Optimized TensorFlow Lite implementation
    • Hundreds of Neural Network models ported
    • 4.6 TOPS performance
  • 512-bit vector register length processor
    • Variable length operations, up to 512-bits of data per cycle
    • Ideal balance of control logic and data parallel compute
    • Decoupled Vector pipeline
    • INT8 to INT64 integer data type
    • BF16/FP16/FP32/FP64 floating point data type
  • Performance benchmarks
    • 5.75 CoreMarks/MHz
    • 3.25 DMIPS/MHz
    • 4.6 SpecINT2k6/GHz
  • Built on silicon-proven U7-Series core
    • 64-bit RISC-V ISA
    • 8-stage dual-issue in-order pipeline
    • Coherent multi-core, Linux capable
  • High performance vector memory subsystem
    • Memory parallelism provides cache miss tolerance
    • Virtual memory support with precise exceptions
    • Up to 48-bit addressing
  • Multi-core, multi-cluster processor configuration, up to 8 cores

Intelligence X280 Development Kit

Dev Kit Deliverables

  • RTL Evaluation
  • Test Bench RTL
  • Software Development Kit
  • FPGA Bitstream
  • Documentation
Solution Overview

SiFive Intelligence

SiFive Intelligence is an integrated software + hardware solution that addresses energy efficient inference applications. It starts with SiFive’s industry-leading RISC-V Core IP, adds RISC-V Vector (RVV) support, and then goes a step further with the inclusion of software tools and new SiFive Intelligence Extensions, vector operations specifically tuned for the acceleration of machine learning operations. These new instructions, integrated with a multi-core capable, Linux-capable, dual-issue microarchitecture, with up to 512b wide vectors, and bundled with TensorFlow Lite support, are well-suited for high-performance, low-power inference applications.

Intelligence Series Highlights

Key Features

  • Fully-compliant with the RISC-V ISA specification
  • Up to 8+1 coherent high-performance RISC-V application processors
  • Supports an in-cluster coherent combination of application processors with real-time processors (U and S cores)
  • Low latency caches
  • High -performance L1 memory microarchitecture
  • Physical memory protection
  • Private cache /cache locking capability for mission critical computing


  • AI/ML Inference and Training
  • Enterprise Switching/Routing/Storage, Smart NICs
  • Edge Analytics, Big-Data Analytics
  • Autonomous Machines
  • Edge Compute
  • 5G Infrastructure/Base Stations
Core Evaluation

From idea to reality.

Ready to see your code in action? The SiFive Intelligence X280 Development Kit enables evaluation of SiFive RISC-V Core IP.

Key Deliverables

Evaluation RTL

  • Full-Functional, synthesizable Verilog RTL
  • Run it in your own simulator
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