Ring-40mm
About the Ring-40mm PCB
Ring-40mm is an open source PCB design by candykingdom, published on GitHub. It is a 2-layer board measuring 40.1 × 46.4 mm, with 45 components from 5 distinct parts.
By type, the board carries 21 capacitors, 20 diodes, 2 connectors and 2 resistors.
It belongs with the rf & radio designs in this gallery.
From the project
Small blinkenlight boards that sync up using radios
Wireless LED control for Burning Man art installations, bikes, and wearables. Devices driving WS2812 strips self-organize over 915 MHz RFM69 radios into a flood mesh with exactly one master, share a network clock via heartbeats, and render effects as pure functions of network time — so every device animates in sync without streaming frames.
New to the project? Start with GETTING_STARTED.md. Working in the code (human or agent)? The mental model lives in docs/index.md and the shared Claude Code/Codex ground rules in CLAUDE.md.
Ring-40mm bill of materials (BOM)
45 components, 5 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 2 | Conn_01x03 | PinHeader_1x03_P2.54mm_Vertical | J1, J2 |
| 20 | XL-1010RGBC-WS2812B | XINGLIGHT-XL-1010RGBC-WS2812B | D1, D2, D3, D4, D5, D6, D7, D8 +12 |
| 20 | 100NF 100nF | C_0402_1005Metric | C1, C2, C3, C4, C5, C6, C7, C8 +12 |
| 1 | 22UF 22uF | C_0805_2012Metric | C21 |
| 2 | 560 | R_0603_1608Metric_Pad0.98x0.95mm_HandSolder | R1, R2 |
Ring-40mm design files
The KiCad project lives in the candykingdom/firefly2 repository on GitHub; these links point at the commit this page was built from.
Ring-40mm: common questions
How big is the Ring-40mm PCB?
The Ring-40mm measures 40.1 × 46.4 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Ring-40mm?
45 components, from 5 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Ring-40mm design files?
From the candykingdom/firefly2 repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Ring-40mm design in my own project?
The repository has no license, so all rights stay with candykingdom. Use it as a reference, and ask the author before reusing the design.
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