RE: nrf51822 ACD pins

Stefan Birnir Sverrisson — Mon, 05 Oct 2015 14:51:49 GMT

There are also ADC examples available on Nordic's Github.

Yes, the ADC only ranges positive voltages.

As stated in the nRF51 Series Reference Manual v3.0, table 311, you can measure different voltage range on the input with adjusting the prescaling of the ADC. with e.g. 1/3 prescaling and VBG reference you have range 0V - 3.6V on the input.

RE: nrf51822 ACD pins

Mahesh Venkitachalam — Mon, 05 Oct 2015 01:35:15 GMT

My understanding is that you need to use AREF0/1 only if your input voltage range and the ADC voltage range is not matching.

Have you looked at the nRF51 Series Reference Manual? (Not the product spec.)

There are 5 pages of information on the ADC in the above and it talks about all the issues you mentioned above.

If you are looking for a simple ADC example, here's my project that uses ADC to read light levels from an LDR:

electronut.in/.../

Regards