 a sense amplifier for comparing a resistance in the MTJ cell in said first bit sub cell with {HEAD ~ a resistance} in {TAIL ~ the MTJ cell} in said second bit sub cell 
a sense amplifier for comparing a resistance in the MTJ cell in said first bit sub cell with { HEAD ~ a resistance } in { TAIL ~ the MTJ cell } in said second bit sub cell
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH