| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor memory that enables proper data read while preventing a read error.SOLUTION: A column control circuit 2 and a row control circuit 3 apply a writing voltage for writing data and a reading voltage for reading data to memory cells MC through bit lines BL and word lines WL. A sense amplifier 2b detects data held in memory cells MC on the basis of a current flowing through the bit lines BL. In writing operation, different resistance values are applied to each of n memory cells MC constituting one unit, and the writing voltage is applied such that the resistance values of the n memory cells in one unit are all different values. In reading operation, the resistance values of the n memory cells constituting one unit are compared with each other, and n! kinds of data are read from one unit. |
