LoRa module in DIL form

Murata produces LoRa module CMWX1ZZABZ-xxx based on SX1276 transceiver and STM32L072CZ microcontroller. The soldering of the LGA module is not very hobby-friendly. I constructed small breakout PCB for this module with additional buck/boost switcher and place for SMA connector. The transceiver features the LoRa®long-range modem, providing ultra-long-range spread spectrum communication and high interference immunity, minimizing current consumption. Since CMWX1ZZABZ-091 is an “open” module, it is possible to access all STM32L072 peripherals such as ADC, 16-bit timer, LP-UART, I2C, SPI and USB 2.0 FS (supporting BCD and LPM), which are not used internally by SX1276.

LoRa breakout board

 

Microcontroller features

  • CMWX1ZZABZ-091 LoRa® module with STM32L072CZ
  • ARM® 32-bit Cortex®-M0+ CPU
  • 32 MHz max CPU frequency
  • VDD from 1.65 V to 3.6 V
  • 192 KB Flash
  • 20 KB SRAM
  • GPIO (40) with external interrupt capability
  • General-purpose Timer (4)
  • Basic Timer (2)
  • Low Power Timer
  • SPI (6)
  • I2S
  • I2C (3)
  • USART (4)
  • Low-power UART
  • USB 2.0 full-speed
  • 12-bit ADC with 13 channels
  • 12-bit DAC (2) with 1 channel each
  • Comparators (2)
  • RTC
  • Capacitive sensing channels (19)
  • Random Generator (TRNG for HW entropy)

Board features

  • Dual-in-Line form factor with 100 mils pitch suitable for prototyping
  • On-board SWD connector
  • Flexible board power supply
    • external 3,3V source
    • External battery (single Li-xx cell or 2/3 LRxx cells)
  • On-board SMA connector and output RF filter

Board schematic and assembly drawing

Schematic is available here: https://github.com/s54mtb/lora_breakout/raw/master/hw/lorabreakout-sch.pdf

Assembly drawing

Gerber files and altium project

Files are here: https://github.com/s54mtb/lora_breakout/tree/master/hw

Board pinout

LoRa breakout board – pinout

GITHUB repository: https://github.com/s54mtb/lora_breakout

 

Leave a Reply