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