Olimex Launches UEXT-CH390 Ethernet Module
The compact module adds wired Ethernet to Raspberry Pi Pico and ESP32-based boards over SPI.
Updated on Nov. 6, 2026 in Semiconductors
Olimex has introduced the UEXT-CH390, a compact hardware module that adds Ethernet connectivity to microcontroller boards. Built around the WCH CH390 SPI-to-Ethernet controller, it supports speeds of up to 100 Mbps.
Why it matters
Adding wired Ethernet to low-cost microcontroller boards gives hobbyists and developers a more reliable network connection than Wi-Fi in many embedded projects. The module's standard UEXT interface makes it easy to attach to existing hardware.
The module communicates with the host over SPI and draws its 3.3V supply through the UEXT or pUEXT connector. The CH390 includes packet buffering and a preprogrammed MAC address, though independent benchmarks are not yet available.
The players
Olimex
Olimex is a Bulgarian hardware company known for open-source development boards and accessories for embedded systems.
The details
The UEXT-CH390 works with Raspberry Pi Pico and Pico 2 boards as well as ESP32-S3, ESP32-C3, ESP32-C5, and ESP32-C6 modules. It includes both a standard UEXT interface and a 1mm pitch pUEXT interface, and Olimex has also released an RP2040 driver for ESPHome that extends CH390 support to Raspberry Pi Pico systems.
Timeline
Shipping is scheduled to begin on 9 November 2026.
The Tech Race
The module packages the WCH CH390 controller into a standard UEXT form factor, following the approach of adding discrete networking chips to small boards for hobbyist use. It positions wired Ethernet as an option alongside the Wi-Fi-first connectivity common on Pico and ESP32 platforms.
Developers building networked embedded projects can add a wired Ethernet connection without redesigning their boards around the module. The €4.95 pre-order price makes the option affordable for hobby and prototype work.
The takeaway
Wired Ethernet remains a practical option for microcontroller projects where reliability matters more than wireless convenience. Developers evaluating connectivity for embedded systems should weigh this module against Wi-Fi alternatives.
What happens next
Shipping for the UEXT-CH390 module is scheduled to begin on 9 November 2026.
Further reading
Explore more semiconductor developments that shape embedded computing hardware.
Source note: This article includes information reported by Electronics For You - Official Site ElectronicsForU.com.
