31.3.2.3 DAC as Source For Internal Peripherals
The analog output of the DAC is internally connected to both the AC and the ADC and is available to these other peripherals when the DAC is enabled (ENABLE=1 in DAC.CTRLA). When the DAC analog output is only being used internally, it is not necessary to enable the pin output driver (i.e. OUTEN=0 in DAC.CTRLA is acceptable).
Note: Only DAC0 has an
output driver for an external pin.