⚡ Olimex UEXT-CH390 adds wired Ethernet

Olimex has announced the UEXT-CH390, a small open source hardware module designed to add 100 Mbit wired Ethernet connectivity to embedded boards. This solution targets devices equipped with a UEXT or pUEXT connector, including Raspberry Pi PICO, PICO2, and various ESP32 models that lack native wired network interfaces. The module leverages Olimex’s proprietary UEXT standard, which serves as a common interface for add-on boards across different microcontroller platforms.

The hardware is built around the WCH CH390 SPI-to-Ethernet controller, enabling network access via the Serial Peripheral Interface bus. This approach allows developers to integrate Ethernet capabilities without requiring complex board redesigns or additional power management circuits. The physical footprint of the module is compact, measuring 50 x 21 mm, which facilitates integration into space-constrained projects while maintaining compatibility with existing UEXT headers.

By providing a standardized add-on solution, the UEXT-CH390 addresses the connectivity gap in many popular microcontroller boards. It offers a direct path to wired networking for users who prefer the reliability of Ethernet over wireless alternatives. The open source nature of the hardware design further supports customization and community-driven improvements for specific application needs.