RAK3172 + Join fail + Battery powered



We are using RAK3172 powered through 3.6V 2700 mAh battery pack with max constant current of 100 mA and max pulse current of 200 mA.
Here RAK3172 fails to join.
It looks that RAK3172 needs more current than battery is providing (correct me if I am wrong).
Can you please help us to use better way to do this so that we can operate device on battery properly.



Does the RAK3172 join the network if powered different without the current limitations?

Yes it is, if powered through USB or any other power supply other than battery.

Are you using a LiSOCl2 battery?

In this case you will have to add a super cap like the 1F CHP ==> CHP5R5L105R-TWQ Electronic Components The super capacitor FET 5.5V1F N-Channel New Original CHP5R5L105R-TWQ

That’s what we are using when supplying from LiSOCl2 like in our SensorHub.

Can you please help us to understand better?
What do you mean by add a super capacitor? Is it parallel to battery?
We are not able to find sensor hub schematic for reference.
Please help.

The super cap has to be parallel to the battery.

I referred to SensorHub as a device where we applied this method. But the design of the SensorHub is not public.

Does it need any additional circuitry or only super capacitor is sufficient?
If you have a sample circuit please share.
Please note that we have connected capacitor across battery but device is not getting started.

A “normal” capacitor will not be enough.
The super cap can be connected parallel to the battery, no additional circuit required.

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