Power consumption with different supply voltages

[asgeirsh]

Is there a graph available for the internal power regulators efficiency / current consumption at different supply voltages and temperatures for the nRF9160(-SICA)? We're currently evaluating different batteries, and would like to know if there is a notable difference at 3V and 5V compared to the 3.7V used in the current consumption tables in the specification. 

The end product is expected to be used outside, so if there are graphs/data available relating power consumption to temperature as well, we would welcome those.

[Amanda Hsieh]

Hi Asgeir, 

There is the Modem current consumption at 85 °C. I am asking the internal for your requirement, but I cannot promise anything. 

-Amanda H. 

[Amanda Hsieh]

Hi Asgeir, 

I got the following reply from the team:

We have some PMU standalone efficiency measurement results at different VBAT levels. But just looking at those numbers will not tell the overall nRF9160 efficiency. Also, the internal regulators change the mode from low power mode to performance mode depending on what the modem is doing. The modem firmware controls the modes of the internal regulators. So I think it will be very hard to assess overall efficiency based on regulators efficiency curves. 

Would it be possible to provide some certain use case that we could run with full nRF9160 setup where the efficiency matters the most? Then we could run the case with T = [-30, 25, 85]C and VBAT = [3.3, 3.7, 5.0]V and provide the current waveforms. 

Please note that modem PA can run only down to 3.3V (with full 23dBm power assumed) in certain bands, only some bands may be able to run at 3.0V.

-Amanda H.

[asgeirsh]

The use case was for outside ATEX-rated environments where some 3.0V-batteries are pre-certified, which would make our job somewhat simpler. We were worried about power efficiency and performance with that low a VBAT voltage, even if the batteries have a very flat voltage curve even under load.

With the fact that the modem is negatively affected in some bands by that voltage, we'll look into alternatives. Thanks for your help!