| 摘要 |
PROBLEM TO BE SOLVED: To avoid concentration of a writeback current in a destructive readout semiconductor memory device. SOLUTION: A switch circuit 24 is provided between each bit line 21 and each sense amplifier 26. In writeback, the switch circuits are turned on at staggered time points. In readout, the switch circuits are turned on to read memory cell data to the sense amplifiers while the sense amplifiers are turned off, and the switch circuits are then turned off temporarily. After that, the sense amplifiers are turned on to amplify the read data. The switch circuits are subsequently divided into groups and turned on again to write back the data amplified by the sense amplifiers to the memory cells. The switch circuits are divided into groups to be turned on at staggered time points during the writeback, to thereby avoid concentration of the writeback current in one time period. COPYRIGHT: (C)2010,JPO&INPIT |
