Hitachi, Ltd.

Masatoshi Sakamoto

Masatoshi Hasegawa

Hiroshi Otori

Mitsugu Kusunoki

Michiaki Nakayama

A semiconductor integrated circuit device including a memory circuit with both high access efficiency and high memory efficiency in a simple configuration is provided. In a memory read control circuit, burst length is changed based on whether or not a read instruction is issued at a cycle after a cycle at which a read instruction /R is issued. And, in a memory write control circuit, burst length is changed based on whether or not a write instruction is issued at a cycle before a cycle at which a write instruction /W is issued.

Synchronous memory circuit

A semiconductor memory device that satisfies needs of both a large number of memory banks and a higher operation speed is provided. A semiconductor memory device includes a plurality of data terminal pads, and a plurality of memory banks independently subject to memory access. Each of the memory banks is divided into a plurality of submemory banks. The data terminal pads are also divided into a plurality of groups so as to be associated with submemory banks obtained by the division. Blocks each including submemory banks obtained by the division and data terminal pads associated with the submemory banks are arranged so as not to overlap each other on a semiconductor chip.

Semiconductor memory device and semiconductor device

A Y selection line for write for controlling operations of a column selection switch within a write amplifier and a Y selection line for read for controlling operations of a column selection switch within a read amplifier are provided individually and the column selection switch within the read amplifier is set to the non-operating condition during the write operation. Accordingly, a through-current during the write operation may be reduced. In this case, the write IO line and read IO line are allocated crossing sense amplifier columns, while the column selection line for write and column selection line for read are allocated in parallel to the sense amplifier columns.

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Hamura, Japan

Masatoshi Sakamoto