The DA converted {HEAD ~ circuit unit} is arranged between the comparator circuit unit and {TAIL ~ the arithmetic operation amplifying circuit unit} 
is arranged between
The DA converted { HEAD ~ circuit unit } is arranged between the comparator circuit unit and { TAIL ~ the arithmetic operation amplifying circuit unit }
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL