Mitsubishi Denki Kabushiki Kaisha

Kazuhiko Takami

Mikio Asakura

Yoshito Nakaoka

Kiyoomi Oshigoe

Data of a plurality of memory cells are read on a plurality of first data lines and combined by a combination/rewrite circuit and transmitted on a second data line and the combined data is written back to the first data line. In combining data, the combination/rewrite circuit performs an addition. Mirrored data can be improved in reliability and a function of correcting an error of the mirror data can also be implemented.

Semiconductor memory having mirroring function

A semiconductor memory device according to the present invention includes a block determining portion determining a difference in arrangement between a normal cell and a spare cell which replaces it, a data scramble controlling circuit generating a scramble ON signal when a normal cell is replaced by a spare cell and the spare cell stores inverted data, a scramble circuit inverting data to be written in response to the scramble ON signal, and a scramble circuit inverting data to be read in response to the scramble ON signal.

Growing community of inventors

Hyogo, Japan

Kazuhiko Takami