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Lora sx1276 low power on listen mode

Semtech Transceivers
#1

Hi all,

I am a beginner on Lora, and it’s been a few weeks that I try to have a low consumption while having the possibility to detect the reception of messages.
I tried with the sandeepmistry library and I can reach 1uA in sleep mode but if I understand correctly, we can’t be notified when we receive messages in sleep mode but in idle mode we can. 1,6 to 1,9 mA on standby mode which is too much.
But unfortunately this library does not offer idle mode (standby and sleep only).
Before I completely abandon the mission I was wondering if someone could confirm me that it is not possible or if it is possible to help me with any library that can do it preferably with Arduino.
I use the sx1276 module and according to the datasheet it would be possible (IDDIDLE):

https __user-images.githubusercontent.com_51214539_213898554-3ada9577-cf71-4d13-8223-60e52801de05
https __user-images.githubusercontent.com_51214539_213898554-3ada9577-cf71-4d13-8223-60e52801de05913×431 81.5 KB

And looking this official video about low consumption I did nod head anywhere about the idle mode, that make me think it may not be possible.
I’m not using LoraWan I just need sending message between 2 Lora powered by a coin battery CR2032, so few uA as consumption should be good to stay at least 1 year.

#2

To receive messages, the LoRa device receiver has to be powered, it takes around 12mA.

You cannot receive messages in idle mode because the receiver is off.

#3

Thank you i will be able to move on.

#4

Good Answer… but to clarify the question…
The reason Idle mode isn’t mentioned in low power is it basically sleep mode.
Essentially its Sleep with RC enabled, its used to periodically wake the receiver so it can listen for incoming frames. (Beacon mode)
When done right, this can significantly reduce the current in an always on scenario.
see page 118 and following of datasheet for more info.

#5

I have seen this diagram and its theoretical scenario many times without having any value for the power consumption or an example to test it on Arduino. Even datasheet did not provide value, which make me have a doubt about the applicability.

  1. At what level do you “significantly reduce the current”?
  2. And if it was tested and it’s really low, do you have an example?
    Thanks
#6

That section of the datasheet describes the use of the sequencer, which is not available in LoRa mode ?