The first comparator group 10a and the second comparator group 10b each have a plurality of {TAIL ~ comparators} for comparing {HEAD ~ the input analogue signal} with a reference voltage 
The first comparator group 10a and the second comparator group 10b each have a plurality of { TAIL ~ comparators } for comparing { HEAD ~ the input analogue signal } with a reference voltage
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH