Beyond the CPU and GPU: SiFive in Datacenter Infrastructure
How embedded RISC-V processors in NICs, retimers, optics, switches, and security chips are overcoming modern scaling limits
Vendor:
Sifive, Inc.
Category:
CPU
S51 Low-power 64-bit MCU RISC V core
The SiFive S51 Standard Core is a 64-bit embedded processor, fully compliant with the RISC-V ISA.
Overview
The SiFive S51 Standard Core is a 64-bit embedded processor, fully compliant with the RISC-V ISA. A small-footprint, low-power design makes the S51 ideal for devices that require a tiny system controller in a larger 64-bit SoC. The S51 can also be used as a standalone controller for networking, storage, or other high-performance embedded applications
Key features
- Fully compliant with the RISC-V ISA specification
- RV64IMAC Support
- RV64I - 64-bit RISC-V with 32 integer registers
- Integer Multiplication and Division (M) support
- Atomic Mode (A) support for high-performance, portable software
- Compressed Mode (C) support for better code density
- Machine and User Mode Support
- In-order, 5-6 stage variable pipeline
- Advanced Memory Subsystem
- 16KB, 2-way Instruction Cache
- Instruction Tightly Integrated Memory (ITIM) option
- Up to 64KB Data Tightly Integrated Memory (DTIM) support
- Support for up to 40 physical address bits
- Efficient and Flexible Interrupts
- Local interrupts w/ vectored addresses - up to 16
- Platform Level Interrupt Controller (PLIC) - 511 interrupts w/ 7 priority levels
- RISC-V Core Local Interruptor (CLINT) - 1 timer, 1 SW
- 8-Region Physical Memory Protection (PMP)
- High performance AMBA or TileLink Interface
- 2.87/1.7 DMIPS/MHz (Best Effort/Legal)
- 3.01 CoreMark/MHz
Block Diagram
S51 block diagram
What’s Included?
- RTL Evaluation
- Test Bench RTL
- Software Development Kit
- FPGA Bitstream
- Documentation
Specifications
Identity
Part Number
S51
Vendor
Sifive, Inc.
Type
Silicon IP
Compute
CPU Architecture
RISC-V
Files
Note: some files may require an NDA depending on provider policy.
Provider
HQ:
USA
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Frequently asked questions about CPU IP cores
What is S51 Low-power 64-bit MCU RISC V core?
S51 Low-power 64-bit MCU RISC V core is a CPU IP core from Sifive, Inc. listed on Semi IP Hub.
How should engineers evaluate this CPU?
Engineers should review the overview, key features, supported foundries and nodes, maturity, deliverables, and provider information before shortlisting this CPU IP.
Can this semiconductor IP be compared with similar products?
Yes. Buyers can compare this product with similar semiconductor IP cores or IP families based on category, provider, process options, and structured technical specifications.