34.1 Overview

The Analog Comparator (AC) supports multiple individual comparators. Each comparator (COMP) compares the voltage levels on two inputs, and provides a digital output based on this comparison. Each comparator may be configured to generate interrupt requests and peripheral events upon several different combinations of input change.

Hysteresis can be adjusted to achieve the optimal operation for each application.

The input selection includes four shared analog port pins and several internal signals. Each comparator output state can also be output on a pin for use by external devices.

The comparators are grouped in pairs on each port. The AC peripheral implements one or two pairs of comparators. These are called Comparator 0 (COMP0) and Comparator 1 (COMP1) for the first pair and Comparator 2 (COMP2) and Comparator 3 (COMP3) for the second pair. They have identical behaviors, but separate control registers. Each pair can be set in window mode to compare a signal to a voltage range instead of a single voltage level.

Note: The second pair of comparators mentioned above (the AC1 module) are only available on the ‘L’ variant devices. Refer to the Register Summary for start address of the AC1 module.