| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor memory in which a DRAM itself has plural ports, plural addresses can be accessed simultaneously, and enlarging of wafer area can be evaded. SOLUTION: Memory blocks B11-B41 are commonly connected to a common wiring JB1, memory blocks B12-B42 are commonly connected to a common wiring JB2, memory blocks B13-B43 are commonly connected to a common wiring JB3, and memory blocks B14-B44 are commonly connected to a common wiring JB4. When ports P1, P2 access memory blocks connected to common wiring being different, simultaneous access can be performed by controlling switches S11-S14 and S21-S22. When ports P1, P2 access memory blocks connected to common wiring being same, after accessing of a port previously starting to access is finished, accessing of the other port is started. It can be performed in also a semiconductor memory having three ports or more. |
