I am using a PIC16F18854 with a stable VDD of 5.0V. Tried multiple chips. Code has been primarily generated using MCC and verified with the datasheet.
ADREF: ADNREF = VSS, ADPREF = FVR_buf1
FVRCON: ADFVR = 4x, FVREN = enabled
- The ADC range appears to be VSS->VDD; changing VDD affects the ADC output
- The ADC acts as if it is being referenced to VDD (between 4.75V-6V)
- Changing just one bit of FVRCON to select to 2x or 1x works as expected - a reference 2.048V/1.024V and the ADC performs conversions. The output is stable when varying the supply voltage.
Could anything be leading to such an issue? Or a silicon/datasheet error?