Proximity App battery service not changing

RE: Proximity App battery service not changing

Einar Thorsrud — Wed, 24 Apr 2019 13:44:20 GMT

Hi,

Yes, the ADC has a dedicated input connected to VDD. However, this is in fact not a very good way of measuring the battery voltage, as the voltage will typically drop when the ADC is enabled, drawing a lot of current. The voltage drop depends on the current charge of the battery, the internal resistance of the battery and the current consumption of the board at the time of sampling.

RE: Proximity App battery service not changing

rahul1 — Tue, 23 Apr 2019 14:40:02 GMT

I am powering the board using an external battery connected to the vdd pin. I am a bit confused of how the conversion works. Can the board be both powered by the battery and calculate it’s percentage value if it is connected to the vdd pin?

RE: Proximity App battery service not changing

Einar Thorsrud — Tue, 23 Apr 2019 14:34:30 GMT

Hi,

You should get a sensible number provided that you wait 180 seconds. In that case the battery level is calculated by battery_level_in_percent(), and should be just a few percent. How do you power the board? I assume you have verified the supply voltage? What ADC reading do you get if you put a breakpoint in the adc_event_handler and inspect the batt_lvl_in_milli_volts value?