Hi, this is a reference schematic from TI for one of their smart plugs. My questions are specifically around the Metrology section on page 1 that measures AC mains voltage and current. I understand that U1B,C,D and U7B,C,D form an instrumentation amplifier. I'm not quite sure what is happening in the stage after this. The non-inv terminals of U1A and U7A seem to be tied to Vcc? Also is that combination of resistors and capacitors dividing Vcc to a lower value? How do I determine what voltage value is at the non-inv terminals? Also how is this aiding in determining voltage and current?
Second part: What are these metrology analog filters? Any help deciphering this would be really appreciated.
Second part: What are these metrology analog filters? Any help deciphering this would be really appreciated.
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