| 摘要 |
<p>When a memory cell area as a unit of erasing, is defined as a sector (S) and units of reading and/or writing are defined as blocks (B0 to B3) in the section, a block address (BA) selecting one of the blocks (B0 to B3) is held in a block address buffer (BAB) (3). The holding operation is performed prior to a reading or writing operation, and according, the block address need not be input again in the following reading or writing operation. One of selection signals (YDn) (n = 0 to 3) is selected according to the held block address (BA), and one of the blocks is selected according to the selection signals (YDn). Since this condition is maintained until the block address (BA) held in the block address buffer (BAB) (3) is rewritten, the block address (BA) need not be input and decoded each time reading or writing operation is performed and the access operation can be performed at a high speed and with a low current consumption.</p> |
