Projects / OpenDongle

OpenDongle

A compact, open-source USB Type-A 2.4 GHz wireless receiver — small enough to disappear inside a standard nano-receiver shell.

2.4 GHz receiver

A compact USB Type-A wireless receiver with a WCH-derived 2.4 GHz PCB antenna tuned for 0.8 mm FR-4.

Nano-sized

A two-layer board roughly 16 × 10 mm — small enough to sit inside a standard nano-receiver shell.

RISC-V inside

Built around WCH RISC-V wireless MCUs with native USB, in two interchangeable hardware variants.

Fully open

Firmware and tools under Apache 2.0; hardware under the CERN Open Hardware Licence (Weakly Reciprocal).

What is OpenDongle?

OpenDongle is an open-source keyboard dongle: a PCB-edge USB Type-A connector, a WCH-derived 2.4 GHz PCB antenna on 0.8 mm FR-4, and a two-layer board built around a WCH RISC-V wireless MCU with native USB. The whole assembly is small enough to fit inside an off-the-shelf nano-receiver enclosure.

The design ships as complete KiCad 10 projects. Every symbol and footprint resolves from the project directory via ${KIPRJMOD}, so nothing has to be added to your global KiCad libraries, and each board can be electrically verified from the command line with kicad-cli.

Hardware implementations

Two variants share the same concept and antenna, and differ in the MCU and its power arrangement. Pick whichever part you can source.

VariantMCUBoard sizePowerStatus
CH570WCH CH570Q (DFN-10)16.4 mm × 10.0 mmVBUS direct to V5, internal 3.3 V regulatorAvailable
CH592WCH CH592D (QFN-20)16.35 mm × 9.90 mmVBUS via XC6206 3.3 V LDOAvailable

Repository layout

Licensing

OpenDongle is split-licensed so both the software and the hardware are genuinely open. Firmware and tools are released under the Apache License 2.0, and the hardware designs under the CERN Open Hardware Licence Version 2 — Weakly Reciprocal.