RFM95W LoRa Radio Module
Long-range, low-power LoRa transceiver for IoT sensor networks.
Wiring & code for
RFM95W practical reference
A long-range LoRa transceiver enabling kilometer-scale, low-power wireless links for remote sensor and IoT networks. The RFM95W is built around the same Semtech SX1276 LoRa chip used across the popular RFM9x module family, packaged with a shielded metal can and matching antenna circuitry for reliable performance — it's a common choice for LoRaWAN-based sensor nodes, The Things Network deployments, and any project needing long-range, low-bandwidth wireless data links well beyond Wi-Fi or Bluetooth range.
Key specifications
- Chipset: Semtech SX1276 LoRa transceiver (also branded HopeRF RFM95W)
- Frequency band: 868MHz (EU) or 915MHz (US) variants — check the specific part number for your region
- Operating voltage: 1.8V–3.7V DC (3.3V typical — NOT 5V tolerant)
- Operating current: ~10-12 mA RX, up to ~120 mA TX at maximum +20dBm output power
- Transmit power: Up to +20 dBm (100mW), software-configurable
- Range: Several kilometers line-of-sight, 10+ km reported in favorable rural/open conditions
- Modulation: LoRa chirp spread spectrum with configurable spreading factor, bandwidth, and coding rate for range/data-rate tradeoffs
- Protocol support: Compatible with LoRaWAN stacks (e.g. for The Things Network) or simple point-to-point LoRa links
- Interface: SPI, plus DIO interrupt pins for TX-done/RX-ready signaling
Pinout and connection notes
Confirm you're buying the correct frequency variant (868MHz vs 915MHz) for your region's ISM band regulations before wiring up a project — the two are not interchangeable. Like the RA-02, this module is 3.3V-only SPI and needs a level shifter when paired with 5V boards, and an antenna must always be connected before transmitting to avoid damaging the power amplifier.
- 3.3V: Power, 3.3V DC only
- GND: Ground
- MOSI: SPI data in
- MISO: SPI data out
- SCK: SPI clock
- NSS (CS): SPI chip select, active LOW
- RESET: Active-LOW module reset
- DIO0-DIO5: Configurable interrupt pins; DIO0 is most commonly wired for TX-done/RX-ready signaling in LoRa libraries
- ANT: Antenna connection — requires a properly tuned antenna for the module's frequency band
Integration checklist
- Confirm the exact part number and breakout-board revision.
- Verify supply voltage, current demand, logic levels, and signal direction against the datasheet.
- Check controller pin assignments and bus address or interface mode against the example code.
- Power up with external loads disconnected, then test signals before full integration.
- If readings or communication fail, check power and ground first, then pin mapping, interface settings, and library initialization.
Troubleshooting and reproducibility
Record the board used, wiring, library/version, supply arrangement, and measured behavior. Use the selected board-specific wiring example as the source of truth. Never assume visually similar modules share identical voltage tolerance or pin order.