A METHOD OF OPERATING THE MEMORY DEVICE AND THE MEMORY SYSTEM

摘要

Provided is a method for operating a memory comprising a step for changing first lead voltage within a first range to determine whether or not data stored in a memory cell is a first voltage state or a second voltage state and determining first selection lead voltage and a step for changing second lead voltage within a second range to determine whether or not the data stored in the memory cell is a third voltage state or a fourth voltage state and determining second selection lead voltage. The first and second voltage states are different from the third and fourth voltage states. The first voltage state is overlapped with the second voltage state. The third voltage state is overlapped with the fourth voltage state. The difference between the second lead voltage and the voltage of a point which intersects the third and fourth voltage states is bigger than the difference between the first lead voltage and the voltage of a point which intersects the first and second voltage states.