Comparator with configurable operating modes

A comparator system operable in a higher speed first mode and a lower power second mode, the comparator system comprising:

• an adjustable-power gain stage configured to receive a differential input signal and, in response, provide a gain stage output signal, wherein a gain characteristic of the gain stage is substantially constant in the higher speed first mode and the lower power second mode;
• and
• an output stage including a buffer circuit coupled to a buffer input switch and a buffer output switch, the output stage having a high impedance input configured to receive the gain stage output signal and a low impedance output configured to provide a switched output signal at an output node, wherein:
• in the higher speed first mode, the buffer input switch is open, the buffer output switch is closed, and the buffer output switch provides the switched output signal at the output node;
• and
• in the lower power second mode, the buffer output switch is open, the buffer input switch is closed, and the buffer input switch provides a switching voltage at an input of the buffer circuit and the buffer circuit provides the switched output signal at the output node.