51.6.2.7 Differential and Single-Ended Conversions

The ADC has two conversion options: differential and single-ended.

If the positive input is always positive, the single-ended conversion must be used to have full 12-bit resolution in the conversion. If the positive input level may go below the negative input, the differential mode must be used to get correct results.

The differential mode is enabled by writing a '1' to the DIFFMODE bit in the input control register (INPUTCTRL.DIFFMODE).

Both conversion types could be run in single mode or in free-running mode. When the free-running mode is selected, an ADC input will continuously sample the input and performs a new conversion. The INTFLAG.RESRDY bit will be set at the end of each conversion.