32.3.2.3.1 Unbuffered Output as Source For Internal Peripherals
The unbuffered analog output of the DAC can be internally connected to
other peripherals when the ENABLE bit in the Control A
(DACn.CTRLA) register is written to ‘1’. When
only the DAC unbuffered analog output is used, the Output
Buffer Enable (OUTEN) bit in DACn.CTRLA can be
‘0’, freeing the pin to be used by other peripherals.