README.md
# lora-device
Version **0.1.6 / revision C** corrects the drill spacing, duplicate drill, silkscreen, solder-paste and USB locating-hole clearances found in the manufacturing review. J2's exact manufacturer number and JLCPCB code C131339 are included in the BOM and source. The board remains 50 × 78 mm with four layers and two-sided assembly.
**The released files pass the documented digital checks for a bare-board prototype handoff.** JLCPCB CAM/impedance acceptance, assembly sourcing/orientation approval and first-prototype testing remain outstanding. See the [revision-C validation report](https://tscircuit.com/gokul/lora-device/blob/validation/fabrication-report.md).
Manufacturer CAD coverage remains **20 of 55 fitted components**; 35 models are still unverified library or nominal geometry. See [model provenance](https://tscircuit.com/gokul/lora-device/blob/docs/manufacturer-models.md).
A 50 × 78 mm, four-layer tracker combining an ESP32-S3-WROOM-1-N8, a Wio-SX1262 IPEX radio module, and a u-blox SAM-M10Q GNSS antenna module. USB-C supplies power and provides native USB programming. A BQ24074 charges a protected single-cell LiPo at approximately 250 mA, with power-path operation; a TPS63021 supplies 3.3 V.
The source has twelve automatically arranged schematic sections, with no schematic sheet wrapper or page border. It contains no authored `schX` or `schY`. General routing was generated by tscircuit capacity-autorouter 0.0.988, then locally corrected to pass clearance and short checks. The reviewed output is stored in `routing/reviewed-routes.json`; its native autorouter adapter verifies the complete routing-input hash before replay. Short regulator switching connections and the main USB pair use explicit PCB paths. Revision C retains JLCPCB JLC04161H-7628, with a 0.24 mm / 0.16 mm main USB pair for a nominal 90 Ω differential target; two redundant ESD-chip bypass routes were removed. See [JLCPCB order settings](https://tscircuit.com/gokul/lora-device/blob/docs/jlcpcb-fabrication.md).
The sections are USB-C and protection, charger, 3.3 V regulator, power/charge LEDs, ESP32 controller, buttons, link LED, debug pads, battery monitor, LoRa radio, GNSS power/UART, and GNSS receiver. Core reports a missing-sheet warning because sheets are intentionally omitted. Two width warnings refer to deliberate 0.20 mm connector escapes on nets whose main paths are 0.24 mm; the main-path geometry is independently checked. No PCB DRC errors remain.
## Build
```sh
bun install
bun run typecheck
bunx tsci check source
bunx tsci check pin_specification
bunx tsci check netlist
bunx tsci check schematic-placement
bunx tsci check placement
bunx tsci build index.circuit.tsx --autorouter-timeout 12m
```
The toolchain is pinned to tscircuit 0.0.2944 and CLI 0.1.2365, checked against npm on 2026-10-19. These resolve core 0.0.2172 and capacity-autorouter 0.0.988.
## External parts
- A protected 1S LiPo battery rated for 250 mA charging, with a 10 kΩ Semitec 103AT-2-compatible NTC, wired to J2 as pin 1 BAT+, pin 2 GND, pin 3 NTC. Confirm connector polarity before connection; commercial battery cable pinouts vary.
- A 50 Ω antenna covering 865–867 MHz, with the mating cable for the Wio module's IPEX connector. Use the [IPEX Wio-SX1262, Seeed SKU 114993390](https://www.seeedstudio.com/Wio-SX1262-Wireless-Module-p-5981.html), not Wio-SX1262-N.
- A 5 V USB source capable of at least 500 mA. This design defaults to the charger's 500 mA input mode; it does not implement USB-PD or USB-C current-advertisement detection.
- An enclosure with a clear sky view above the GNSS patch, at least 5 mm of nonmetallic clearance, and clearance below the radio for its antenna cable. Keep the battery and antenna cable away from the GNSS antenna and ESP32 antenna zone.
## Operation
The green PWR LED indicates the 3.3 V rail. The amber CHG LED is driven by the charger status output. The blue LINK LED is software controlled. RST resets the ESP32; hold BOOT while pressing RST to enter the ROM downloader. USER is a general-purpose button.
GNSS power defaults off. Firmware enables GPIO7 and communicates over UART1 on GPIO15/16 through a buffer that prevents an unpowered GNSS rail from being back-powered. GNSS backup power remains connected to 3.3 V; removing all board power loses that retention.
No application firmware or receiver/gateway is included. See [firmware interface](https://tscircuit.com/gokul/lora-device/blob/docs/firmware-interface.md) and [design references](https://tscircuit.com/gokul/lora-device/blob/docs/references.md). Region, transmit power, duty cycle and protocol must be configured for the intended deployment; the radio hardware's maximum output is not the operating-power recommendation.
## Deliverables
[Open the revision-C manufacturing archive](https://tscircuit.com/gokul/lora-device/blob/dist/manufacturing/lora-device-rev-c.zip): Gerbers, BOM, placements, assembly drawings, schematic PDF and manufacturing notes.
- `dist/manufacturing/gerbers.zip`: four copper layers, both solder masks/paste/silkscreen layers, outline and plated/nonplated drills.
- `dist/assembly/bom.csv` and `placements-native.csv`: 55 fitted references. J2 and the USB shell tabs require through-hole/selective or hand soldering; TP1–TP3 are bare test pads. The USB signal contacts have top-side stencil apertures.
- `dist/assembly/assembly-top.svg` and `assembly-bottom.svg`: actual pad-1/cathode marks. Read [assembly orientation](https://tscircuit.com/gokul/lora-device/blob/docs/assembly-orientation.md) before importing placements into an assembler's system.
- `dist/schematic/tracker-schematic.pdf`: one A2 landscape PDF of the borderless schematic; SVG/PNG previews are alongside it.
- `dist/model/tracker-glb.zip`: extract `tracker.glb` for the reviewed top/bottom/side 3D model. The failed STEP export is excluded; see the historical findings report.
- `dist/manufacturing/tracker-kicad.zip`: editable exported KiCad files for reference. Gerbers are the checked fabrication authority.
[Assembly notes](https://tscircuit.com/gokul/lora-device/blob/docs/assembly.md) describe the stack-up/USB impedance handoff, battery connector, exact module variant, and first power-up. [Reproduced tscircuit findings](https://tscircuit.com/gokul/lora-device/blob/validation/tscircuit-findings.md) collect the confirmed tool issues, evidence and suggested contribution scopes. No issues or pull requests were opened.
