| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor memory device which can let a differential amplifier more quickly output a difference of a data signal from a main memory cell and a dummy data signal from a dummy cell. SOLUTION: A circuit pattern of a first and a second dummy memory cell arrays DMY1, DMY2 is made approximate as much as possible to that of a memory cell array MEM. In selecting a memory cell of the memory cell arrays, a matrix position of a main memory cell M, a matrix position of a dummy memory cell DM1 and a matrix position of a dummy memory cell DM2 are agreed with one another. Accordingly, time constants of signal transmission routes of the memory cells are agreed, so that a potential difference of either between a data signal line DL and a first reference voltage line RL1 or between the data signal line DL and a second reference voltage line RL2 can be output quickly from a differential amplifier SA. |
