a pull up voltage supply circuit, connected with the first power supply and {HEAD ~ the second power supply}, for supplying {TAIL ~ the pull up voltage} 
a pull up voltage supply circuit , connected with the first power supply and { HEAD ~ the second power supply } , for supplying { TAIL ~ the pull up voltage }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL