In the case of an N channel device in the output driver, {HEAD ~ the blocking polarity potential} is a negative voltage applied to {TAIL ~ the gate} of the transistor 
In the case of an N channel device in the output driver , { HEAD ~ the blocking polarity potential } is a negative voltage applied to { TAIL ~ the gate } of the transistor
OTH OTH OTH OTH OTH OTH OTH OTH 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 OTH OTH OTH