I am trying to understand how the circuit shown below works. More specifically, I am trying to understand how the comparator outputs only 0 or 12V. (the circuit is from this paper.
Without the 2.2K resistor connecting +12V to the output, I think you have, for the output, +12V if VB>VREF and -12V if VB>VREF.
I am not sure what's going to happen with the resistor in place.