nrf52832 Proxymity Battery Level Circuit

[Amila Karunarathna]

Guys, I am designing a Bluetooth proximity tag using nrf52832 SoC. I have designed and tested the circuit and it works fine.

What is the best method to read the coin cell battery level for my Bluetooth tag? If I use potential divider method will it reduce battery lifetime significantly?

What is the best way?

[Einar Thorsrud]

You do not need any external circuitry at all if you have connected the battery directly to VDD, as the SAADC peripheral can use VDD as a input. This is exactly what is done in the Proximity Application example in the SDK. There you can see how the ADC is configured and sampled.

[awneil]

Depends what you mean by "level" - the voltage level is not a very good indication of the level of charge ...