{TAIL ~ A second transistor} couples at least one logic input of the logic circuit to {HEAD ~ the input} of the amplifier 
{ TAIL ~ A second transistor } couples at least one logic input of the logic circuit to { HEAD ~ the input } of the amplifier
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH