X‑FAB and Efabless Unveil Raven, the First Open‑Source RISC‑V MCU Silicon

In a landmark collaboration, X‑FAB Silicon Foundries and Efabless have announced the successful first‑silicon release of Raven, an open‑source RISC‑V microcontroller unit (MCU) that blends community‑driven digital design with proprietary analog expertise.

Raven was conceived, designed, and taped out in under three months using Efabless’s open‑source design flow. The chip incorporates the PicoRV32 RISC‑V core—a community‑built ultra‑low‑power processor—and has been benchmarked at 100 MHz. Simulations indicate it can reliably run up to 150 MHz, offering a compelling performance‑to‑power ratio for embedded applications.

What sets Raven apart is its hybrid architecture: the top‑level design is fully open source, yet it integrates X‑FAB’s proprietary analog IP. This approach marries the agility of open innovation with the robustness of proven analog solutions, safeguarding critical investments while remaining community‑friendly.

The device is manufactured on X‑FAB’s XH018 process, a flexible 180 nm, 6‑metal node that supports low‑power operation, on‑chip isolation for high‑voltage scenarios, and high‑temperature flash memory. XH018 meets stringent automotive quality standards and is widely adopted across automotive, industrial, and medical sectors.

Raven is now a fully functional reference design, available for free on the Efabless Marketplace. Efabless is already engaging early adopters to develop derivative offerings, reinforcing its open‑innovation ecosystem.

For teams eager to dive into open‑source semiconductor design, X‑FAB offers a suite of complimentary webinars—“Handling of Complex & Diverse IC Designs Made Easier,” “Design Robustness,” and “IC Lifetime Calculation Made Easy”—alongside design kits and process design kits (PDKs) tailored for open‑source IP projects.