Help me understand this BEMF measurement schematic

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Joined Aug 30, 2013
This part of the schematic from the STSPIN32F0251 EVB allows the user to select between various commutation inputs to operate a BLDC motor in sensored and sensor-less modes. Can anyone help me understand the BEMF measurement part? Also, how is that all the inverting input of the opamps come from a single phase? I tried simulating this in LTSpice and I think it works but I don't know why or how and also why the GPIO_BEMF output looks the way it does. The schematic is shown below and the LTSpice file is also attached here. Any inputs and help in understanding this would be really appreciated. Thank you.

Screenshot 2021-09-22 at 9.05.14 AM.png