20261024-2000-air-hub-mg24-module Air Hub radio: RF-star RF-BM-MG24B2 module instead of the chip-down EFR32MG21

• status: completed
• priority: P2
• owner: worker/session-20261015-1500
• createdAt: 2026-10-24 20:00

Description

On 2026-10-24 the owner chose the RF-star RF-BM-MG24B2 (EFR32MG24A420F1536IM48-B, +19.5 dBm, 1536 kB flash, 256 kB RAM, PCB antenna, 17 × 23.35 mm, 36 castellated pads) to replace the chip-down EFR32MG21 with its crystals, +20 dBm match and chip antenna on the Linux carrier (Air Hub / Air Hub Pro) and on the Air Hub Mini. The radio keeps the signed-image switching of GW-07 (BLE central, Zigbee NCP, Thread RCP; Matter over Thread commissioned from the host) and is the platform option R2.

Acceptance criteria:

1. Schematic: module symbol with the data-sheet pinout; UART, RTS/CTS, reset, bootloader pin and SWD on the same port pins as before (PA05/PA06, PC00/PC01, PB01, PA01/PA02); ERC and net verification clean on all three projects.
2. PCB: project footprint from the data-sheet drawing, antenna end on the board edge with a copper keep-out; DRC 0 unconnected and 0 errors on the carrier and the Mini; EMC and SPICE rerun.
3. Docs: spec, design, reference-board page, cost and the READMEs name the module; part count and cost delta recorded.
4. Quality gate: bun run docs:lint && bun run docs:build && git diff --check passes.

ActiveForm

Moving the Air Hub radio to the RF-BM-MG24B2 module

Dependencies

• blocked by: (none)
• blocks: (none)

Notes

Chosen by the owner on 2026-10-24 ("选用RF-Star RF-BM-MG24B2这个") after comparing ZS3L, E72, MGM240P and MGM210P against the BLE / Zigbee / Thread image requirement. Source: RF-star RF-BM-MG24B2 hardware specification V1.0 (2023-03-14). LCSC C5441198, $6.69 @1 / $5.61 @10, stock 0 on 2026-10-24; volume price and CE/RED status to be confirmed with RF-star.

Scope change on 2026-10-24: the owner also approved the HopeRF RFM310-433S2 module in place of the chip-down CMT2300A 433 MHz link (Air Hub Pro only, not fitted on Air Hub), and then limited this task to Air Hub and Air Hub Pro: "only Pro and Hub, not Mini; keep the Mini as it is". The Air Hub Mini is handled in a separate session by the owner; its schematic, board, checks and the Mini sections of the reference-board page (§2.4, §6.1, §7.4, §8) are out of scope here.

Results (Linux carrier): ERC 0, 611 pins / 243 nets with 0 mismatches; Pro DRC 0 unconnected, 0 clearance / short, schematic parity 0; EMC 67 findings (23 errors, all in the RJ45 pin field, the RMII fan-out and known false positives, plus MG24_SWCLK); SPICE 26 subcircuits, 25 pass, 1 skip. Pro parts 164 -> 128; per-board cost at 100 boards $50.02 -> $52.28 (Pro), $41.32 -> $42.69 (Air Hub); reference-board totals Air Hub $35.8-45.0, Pro $43.3-48.6.