E32-900T20D LoRa Module (SX1276) - 868MHz/915MHz 20dBm 5.5km Range
The E32-900T20D is a high-performance wireless serial port module (UART) based on Semtech's SX1276 LoRa solution. It utilizes LoRa spread spectrum technology to provide long-distance transmission, exceptional anti-interference capabilities, and industrial-grade reliability across the 862MHz to 931MHz frequency band.
Key Specifications
- Frequency Range: 862MHz ～ 931MHz (Support ISM Band)
- Transmission Power: 20dBm (approx. 100mW)
- Communication Distance: 5.5km (Under ideal conditions)
- Interface Type: UART (TTL level)
- Size: 16 * 26mm (SMD package with stamp hole)
Technical Parameters
| Main Parameter | Value/Description | Remark |
|---|---|---|
| Modulation | LoRa™ | SX1276 solution |
| Operating Voltage | 2.3V - 5.5V | ≥5.0 V ensures max power |
| Communication Level | 3.3V (TTL) | Risk of burnout if used with 5V TTL |
| TX Current | 120mA | At max 20dBm power |
| RX Current | 16mA | Highly efficient receiving |
| Receiving Sensitivity | -123dBm | At 2.4kbps air data rate |
| Operating Temp | -40°C ~ +85°C | Industrial-grade design |
FAQ
1. Can I directly connect the E32-900T20D UART pins to a 5V Arduino Uno?
Answer: While the module supports an operating voltage (VCC) of up to 5.5V, the communication level (TX/RX) is strictly 3.3V TTL. Connecting it directly to 5V logic pins without a level shifter or series resistors (typically 1k-5k Ω) puts the module at a significant risk of burning down, as specified in the "Communication Level" remark.
2. The specs state "≥5.0V ensures output power." Will it still work if I power it with 3.3V?
Answer: The E32-900T20D has a wide operating voltage range from 2.3V to 5.5V. However, to achieve the full 20dBm (100mW) transmission power required for the 5.5km reference distance, a 5.0V supply is recommended. At 3.3V, the module will function normally, but the transmission power may be slightly lower, reducing the effective range.
3. What happens if my data packet is longer than the 58-byte "TX length"?
Answer: The module features automatic sub-packing. While 58 bytes is the maximum capacity for a single package, the module has a 512-byte buffer. If you send more than 58 bytes via the UART interface, the E32-900T20D will automatically split the data into multiple sub-packets and transmit them until the buffer is cleared.
4. Can I use the same module for both 868MHz (Europe) and 915MHz (USA) projects?
Answer: The E32-900T20D hardware supports a wide frequency band from 862MHz to 931MHz. You can programmatically tune the operating frequency to 868MHz or 915MHz (or any other frequency within the supported range) to comply with local ISM band regulations without needing to change modules.
