A digital multibit non-volatile memory integrated system includes autozero multistage
sensing. One stage may provide local sensing with autozero. Another stage may provide
global sensing with autozero. A twisted bitline may be used for array arrangement.
Segment reference may be used for each segment. The system may read data cells
using a current sensing one or two step binary search. The system may use inverse
voltage mode or inverse current mode sensing. The system may use no current multilevel
sensing. The system may use memory cell replica sensing. The system may use dynamic
sensing. The system may use built-in byte redundancy. Sense amplifiers capable
of sub-volt (1V) sensing are described.