29.3.1 Initialization

For a basic operation, follow these steps:
  • Configure the desired input pins in the port peripheral.
  • Select the positive and negative input sources by writing the Positive and Negative Input MUX Selection bit fields (MUXPOS and MUXNEG) in the MUX Control A register (ACn.MUXCTRLA).
  • Optional: Enable the output to pin by writing a '1' to the Output Pad Enable bit (OUTEN) in the Control A register (ACn.CTRLA).
  • Enable the AC by writing a '1' to the ENABLE bit in ACn.CTRLA.

During the start-up time after enabling the AC, the output of the AC may be invalid.

The start-up time of the AC by itself is at most 2.5 µs. If an internal reference is used, the reference start-up time is normally longer than the AC start-up time.

To avoid the pin being tri-stated when the AC is disabled, the OUT pin must be configured as output in PORTx.DIR.