Olimex Support Forum

Others => UEXT => Topic started by: leo.costa on September 17, 2021, 03:17:51 PM

Title: LoRa868 power consumption
Post by: leo.costa on September 17, 2021, 03:17:51 PM
Hello,
i've just read in the LoRa868 user manual that Lora based devices can work up to 10 years from small lithium battery, but in the same manual in the "Power Supply" paragraph the sleep mode consumption is rated at 0.2mA. With that consumption, not considering the remaining components (uC, peripherals, etc.), and not considering the battery self-discharge, after 1 years 1800 mAh are required. That sleep mode consumption is not compatible with 10 years of battery duration. I think that statements is misleading, my advise to developers is to make the power consumption estimation before starting the development on a module.

Leo
Title: Re: LoRa868 power consumption
Post by: LubOlimex on September 17, 2021, 04:41:10 PM
Thanks for the notice! It is typo in the datasheet... It is 0.2uA in sleep mode...

The values were copy pasted wrongfully from page 14 of the datasheet of SX1276...

Title: Re: LoRa868 power consumption
Post by: kyrk.5 on September 14, 2023, 10:45:28 AM
I have a
PIC32-PINGUINO-OTG
with a
MOD-LoRa868.

I plugged the Lora into the UEXT. It works fine, and now I want to check the current consumption of the whole stuff. Actually I face following problem. The current consumption in sleep mode (measured on battery) is around 700uA. I found that, when I pull down the Lora module, it goes much lover, to around 50uA.
On the schematic it turned out, that on the PIC32 board for the UEXT connector PIN 6 (A4) (DIO2 pin of the Lora module is connected here) is a pull up resistor. Measuring the voltage of this pin during sleep, resulted in 0V. So it is pulled down by the Lora module.

Is there a way to get the Lora Modules DIO2 to go high? I tried to reconfigure it. Nothing. Any tips or tricks?

Currently it is very convenient to plug the module just into the UEXT, and have no wiring. I want to stay with this solution if possible. And if possible, I do not want to alter any board. However maybe as a last action, I can just solder out pull up resistor, hopefully the Sx1276 pins are pushpull pins :)