Devboard

Nano LoRa - RP2350 Based Development Board

An RP2350B-powered development board with long-range wireless connectivity and battery support

Nano LoRa is a custom microcontroller development board designed to bring together the Raspberry Pi RP2350B, LoRa wireless communication, and battery-powered operation in a compact platform for embedded projects.

The project started while I was building a Raspberry Pi Pico-based keyboard. I wanted an affordable, flexible development board that could support wireless projects without requiring a separate radio module or an external battery-management circuit. Nano LoRa is my attempt to build that board from the ground up.

Project status: Custom PCB design published. Board bring-up, firmware examples, electrical measurements, and radio-range validation are not yet documented in this repository.

Highlights

• RP2350B microcontroller — a versatile dual-core microcontroller with a generous GPIO budget for peripherals and expansion.
• LoRa connectivity — intended for low-data-rate, long-range wireless communication.
• Battery support — designed with portable, untethered projects in mind.
• Accessible I/O — pin headers intended to make the board useful for prototyping, custom peripherals, and hardware experimentation.
• Custom PCB design — board design files and manufacturing outputs are included in the repository.

Why I built it

While prototyping custom keyboards and other embedded devices, I kept running into the same trade-off: inexpensive microcontroller boards are easy to find, but combining wireless connectivity, battery support, and useful GPIO access often means adding breakout boards and extra wiring.

Instead of designing around those limitations, I decided to explore what it would take to integrate these capabilities on a single PCB. Nano LoRa is also a hands-on exercise in schematic capture, component selection, PCB layout, power-system design, and preparing hardware for fabrication.

Hardware overview

The precise LoRa transceiver, supported frequency band, antenna interface, battery requirements, connector pinout, and electrical limits should be verified against the schematic before assembling or powering the board. These details have not been independently confirmed in the published README.

Repository structure

Nano_LoRa/
├── PCB/             # PCB design project and associated files
├── gerbers.zip      # PCB fabrication outputs
├── journal.md       # Development notes (currently empty)
├── LICENSE          # CC BY-NC 4.0 license
└── README.md        # Project overview and documentation

Getting started

1. Review the design

Open the files in PCB/ with the appropriate PCB design software. Before ordering components or boards, review:

• The schematic and component footprints
• Power inputs, voltage rails, and battery charging/protection arrangements
• Microcontroller boot and programming connections
• LoRa radio connections and antenna matching/layout
• GPIO header pin assignments and voltage compatibility

2. Fabricate the PCB

1. Download gerbers.zip.
2. Upload the archive to a PCB fabrication service that accepts Gerber manufacturing files.
3. Confirm the board outline, layer count, drill files, thickness, and stack-up against the design requirements.
4. Review the manufacturer's production preview before placing an order.

Important: Gerber files contain board-fabrication information; they do not automatically include a complete bill of materials, pick-and-place file, or assembly instructions. Confirm that all required manufacturing and assembly outputs are available before ordering a populated board.

3. Assemble and bring up the board

For a first revision, use a current-limited bench supply and verify power rails before connecting a battery or enabling the radio. A suggested bring-up sequence is:

1. Inspect the assembled board for shorts and soldering defects.
2. Check resistance between power and ground before applying power.
3. Apply power with a conservative current limit and verify regulated voltages.
4. Confirm that the RP2350B can enter its programming mode and accept firmware.
5. Test basic GPIO functionality.
6. Confirm SPI communication and initialization of the LoRa radio.
7. Perform controlled short-range packet tests before attempting range measurements.
8. Validate battery charging, protection, and current consumption against the schematic and component specifications.

These are recommended validation steps, not a claim that all tests have already been completed.

Potential applications

• Wireless sensor nodes — temperature, environmental, and equipment telemetry
• Remote monitoring — low-bandwidth status reporting where Wi-Fi is impractical
• Battery-powered prototypes — portable embedded experiments
• Custom input devices — controllers and peripherals that can benefit from additional GPIO
• Educational hardware — exploring embedded systems, PCB design, and radio integration

LoRa is suited to small, infrequent data packets rather than high-bandwidth applications such as audio or video streaming. Actual range depends on radio settings, antennas, terrain, obstacles, and local spectrum regulations.

Documentation roadmap

The following would make the design easier for others to reproduce and evaluate:

• Add front/back PCB renders and an assembled-board photo
• Publish a complete BOM with part numbers and quantities
• Add a labeled pinout diagram and schematic PDF
• Document the battery connector, charging behavior, and power limits
• Document the LoRa transceiver, frequency variant, and antenna requirements
• Add a minimal RP2350B firmware example
• Add a basic LoRa transmit/receive demonstration
• Record measured sleep/active/transmit current and practical range tests
• Document revision history and known issues

Design files

• PCB source files
• Gerber manufacturing archive
• Development journal

License

Copyright © 2026 Aayan Shaikh.

This design is published under the Creative Commons Attribution–NonCommercial 4.0 International (CC BY-NC 4.0) license. You may share and adapt the material with attribution for non-commercial purposes. Commercial use requires separate permission.

See the LICENSE file for details.

Author

Aayan Shaikh
Computer Engineering student and hardware developer
GitHub

Designed to make wireless, battery-powered hardware experimentation more accessible.