What is it?

This is a STM32WL based LoRa®/LoRaWAN® dev-board with all the necessary components for rapid prototyping.

Specs (SoC):

• STM32WLE5JC Wireless SoC
• ARM Cortex M4 ultra-low-power MCU
• Integrated SX1262 RF transciever
• Frequency range: 150 MHz to 960 MHz.
• Modulation: LoRa®, (G)FSK, (G)MSK and BPSK
• Transmitter power: programmable up to +22 dBm

Specs cont. (LoRa-E5 module):

• Frequency range: EU868/US915/AU915/AS923/KR920/IN865 (high-band design). FCC and CE Certified
• Ultra-low Power Consumption: as low as 2.1uA sleep current (WOR mode)
• High Performance: TXOP=22dBm@868/915MHz; -136.5dBm sensitivity for SF12 with 125KHz BW
• Long Distance Use: 158dB link budget
• Size: 12mm x 12mm x 2.5mm 28 pins SMT

Penguino power consumption (STM32WL in STOP2 mode w/ RTC enabled, @4.3 VBAT input):

• PWR LED ON: ~550 µA
• PWR LED OFF: ~75 µA (JP2 cut, LED disabled, USB-TTL converter ON)
• PWR LED OFF: ~7.6 µA (JP5 cut, USB-TTL converter disabled)*

*Power consumption can further be reduced by disabling the VBAT monitoring voltage dividers.

Why did you make it?

I needed a breakout board compatible with other Penguino boards so I can evaluate the LoRa-E5 module. At the time there was no dev-board available for it, but later Seeed guys came up with nice selection of dev-boards for this module.

What makes it special?

Unlike the official dev-board from Seeed, this one is purpose designed to be low-power. It also provides better usability thanks to the wide selection of Feather compatible add-ons and expansion boards. Be sure to checkout the awesome-feather repo.

Programming

Device comes with a RGB toggle example preloaded. If you want to try out the LoRaWAN-End-Node demo, please refer to this forked repo.

Notes

Since this was a low volume prototype run I only have 4 left. Default antenna path is routed to the SMA edge connector and the board doesn't come with an antenna. Please make sure you have a male 868/915MHz SMA antenna at hand.