To provide a semiconductor which has a storage region consisting of a plurality of memory cells, wherein the electric power consumption is small and heat generation is small.

The semiconductor having the storage region consisting of the plurality of the memory cells and having a selection line by each unit of the memory cells is provided with a division control means for dividing the storage region to a plurality of blocks consisting of the units of the plurality of the memory cells and a selection means for selecting the selection lines in the block by each of the blocks. The selection means is constituted to select all of the selection lines by each of the blocks, thereby putting the memory cells into an active state in the block units which are portions of the storage region.