I'm surveying LoRa devices and assessing their suitbility for use with RPi. Adafruit have recently released a series of devices that are a board with a RFM9x part attached, both 433MHz and 900MHz. Link: https://www.adafruit.com/product/3073
There is also a dedicated RPi expansion board with the exact same RFM9x part attached from Uputronics. Link: https://store.uputronics.com/index.php? ... duct_id=68
I have concrens that the Adafruit board lists the following in the details:
> ~100mA peak during +20dBm transmit, ~30mA during active radio listening
This far exceeds the RPi GPIO design limits of 16mA/pin (or 51mA total). Thus, would this make Adafruit's device unsuited to be powered by the RPi GPIO?
How is the FRM9x part in the Uputronics being powered without damaging the RPi since it's being directly connected to the GPIO header? Furthermore, the Uputronics product allows two (2) FRM9x parts to be attached on the same board. So isn't that double the current (I) requirements?