said {HEAD ~ internal signal} is issued from {TAIL ~ a connection node} between said fourth P channel MOS transistor and said fourth N channel MOS transistor 
said { HEAD ~ internal signal } is issued from { TAIL ~ a connection node } between said fourth P channel MOS transistor and said fourth N channel MOS transistor
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH