| 摘要 |
An object of the present invention is to realize a flash memory in which word redundancy can be implemented. In a nonvolatile semiconductor memory in which word redundancy is implemented to replace a faulty memory cell with a redundancy nonvolatile memory cell in units of a word line, source lines are a plurality of lines SL1, SL2, SL3, etc., arranged in a one-to-one correspondence with and in parallel with word lines WL1, WL2, etc. The source lines are connected to a first common source line CSL1 via first switching means TrA1, TrA2, etc. that are selectively allowed to conduct owing to voltage applied to word lines for reading or writing. The source lines are connected to a second common source line SCL2 via second switching means TrB1, TrB2, etc. that conduct for erasing. <IMAGE> |
