First and second comparator groups compare first and second analogue signals applied thereto, respectively, with reference voltages and convert the results of {HEAD ~ the comparison} to {TAIL ~ binary signals} to output the binary signals to an encoding circuit 
First and second comparator groups compare first and second analogue signals applied thereto , respectively , with reference voltages and convert the results of { HEAD ~ the comparison } to { TAIL ~ binary signals } to output the binary signals to an encoding circuit
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH