Low voltage comparator with programmable devices to improve input dynamic range

A method for voltage comparison, comprising:

• receiving a first input voltage at a gate of a first input transistor on a first input transistor path of a comparator;
• receiving a second input voltage at a gate of a second input transistor on a second input transistor path of the comparator;
• enabling or disabling a third input transistor path and a fourth input transistor path coupled in parallel with the first input transistor path and the second input transistor path, respectively, based on a configuration mode of operation of the comparator;
• and
• generating an output voltage based on comparison of the first input voltage and the second input voltage.

A calibration circuit, comprising:

• a first multiplexer with a first input coupled to a first input node of the calibration circuit and a second input coupled to a second input node of the calibration circuit;
• a second multiplexer with a first input coupled to a first reference voltage node of the calibration circuit and a second input coupled to a second reference voltage node of the calibration circuit;
• and
• a comparator comprising:
• a first input transistor path including a first input transistor with a gate coupled to an output of the first multiplexer;
• a second input transistor path including a second input transistor with a gate coupled to an output of the second multiplexer;
• a third input transistor path in parallel with the first input transistor path and including a third input transistor with a gate coupled to the first input node;
• and
• a fourth input transistor path in parallel with the second input transistor path and including a fourth input transistor with a gate coupled to the second input node.