51.6.2.6 ADC Resolution

The ADC supports 8-bit, 10-bit or 12-bit resolution. Resolution can be changed by writing the Resolution bit group in the Control B register (CTRLB.RESSEL). By default, the ADC resolution is set to 12 bits. The resolution affects the propagation delay, see also 51.6.2.8 Conversion Timing and Sampling Rate.