| 摘要 |
PURPOSE: To obtain a semiconductor memory which unnecessitates refresh operation with the same constitution as a DRAM and can hold data even if a power source is turned on again after it is turned off once. CONSTITUTION: This device is a semiconductor memory having a memory cell array in which a memory cell consisting of a transistor and a capacitor is selectively arranged at a cross point of plural word lines WL and plural bit lines BL. At the time of 'ACTIVE' in which a power source is turned on, each transistor in memory cells M1 , M3 connected to selected word line WL0 is turned on, and each transistor in memory cells M0 , M2 connected to non- selective word lines WL1 is in a OFF state. At the time of standby in which a power source is turned on, at the time of turning off of a power source, at the time of turning on a power source, and at the time of cutting off a power source, each transistor in all memory cells M0 -M4 is in a OFF state. |
