{HEAD ~ a first buffer} for buffering the positive signal and outputting {TAIL ~ a first output signal} 
for outputting
{ HEAD ~ a first buffer } for buffering the positive signal and outputting { TAIL ~ a first output signal }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL