{HEAD ~ The circuit} includes a first tracking bit line, a second tracking bit line, {TAIL ~ a tracking cell}, and a control logic circuit 
{ HEAD ~ The circuit } includes a first tracking bit line , a second tracking bit line , { TAIL ~ a tracking cell } , and a control logic circuit
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH