An A/D converting circuit converts {HEAD ~ the output voltage} of {TAIL ~ the amplifying circuit} into a digital value by comparing it with reference voltage, and outputs it 
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An A / D converting circuit converts { HEAD ~ the output voltage } of { TAIL ~ the amplifying circuit } into a digital value by comparing it with reference voltage , and outputs it
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH