A first analogue signal and {HEAD ~ a second analogue signal} to be multiplied are supplied to {TAIL ~ a first comparator group} 10a and a second comparator group 10b, respectively 
A first analogue signal and { HEAD ~ a second analogue signal } to be multiplied are supplied to { TAIL ~ a first comparator group } 10a and a second comparator group 10b , respectively
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH