Logic control circuitry 320 is connected to the first tracking bit line and usable to convert {HEAD ~ the voltage change} on the first tracking bit line DBL into {TAIL ~ the SAE signal} 
into
Logic control circuitry 320 is connected to the first tracking bit line and usable to convert { HEAD ~ the voltage change } on the first tracking bit line DBL into { TAIL ~ the SAE signal }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL