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hallard / LoRa-E5-Tiny

LoRa-E5 Tiny cell coin STM32WL LoRaWAN board
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Coin cell operation #1

Open eivholt opened 2 years ago

eivholt commented 2 years ago

Thanks for sharing this tiny board, I plan to base a project on it. I was reading about the peak current draw and was wondering if you have made any progress on experimentation running the circuit on coin cell battery? I recently got a Lora E5 module and have started profiling using Otii Arc. I will post an update on my findings using coin cell and capacitors.

eivholt commented 2 years ago

As a start I got pretty much the same current consumption at TX using the Lora-E5-mini, using AT-commands and the supplied whip antenna. Will proceed to flash custom program using mbed and try to apply the suggested TX-parameters.

Current consumption Lora-E5-mini Whip antenna default

eivholt commented 2 years ago

I believe I have hit the desired TX amplification. Not sure about actual signal reduction, whether it will be a problem for my application. I have a gateway in my house so I need to do some field testing. Here are the stats from my gateway:

rssi": -61, "channel_rssi": -61, "snr": 7.5, "bandwidth": 125000, "spreading_factor": 7

Otii Arc custom rf_switch_config

I will move forward with running on a custom PCB and experiment with coin cell operation.

Thank you so much for sharing your work, you are a true legend!

hallard commented 2 years ago

@eivholt thanks for your feedback,

Changing TX according datasheet reduce consumption but a user saw range decrease https://forum.seeedstudio.com/t/lora-e5-fw-bug-tx-eu868-85ma-too-high-consumption/260126

So not sure what to do, what is real is that this module (same for RAK) as not been designed for low power on EU868, so that's really a shame. Nothing to do until hardware changes on modules.

Let me know your testings, very interesting.

SRSchwab commented 1 year ago

@eivholt Does RAK3172-SiP WisDuo LPWAN SiP solve the issue?