SEMICONDUCTOR MEMORY DEVICE REDUCING WRITE OPERATION PERIOD AND DRIVING METHOD THEREFOR, ESPECIALLY INCLUDING EQUALIZATION UNIT AND SWITCH UNIT TO MAKE ELECTRIC POTENTIAL OF BIT LINES EQUAL

摘要

PURPOSE: A semiconductor memory device and a driving method therefor are provided to reduce a write operation period and thus to prevent the increase of chip size for prefetch method. CONSTITUTION: A sense amplifier unit(13) senses a voltage difference between a positive and a negative bit line sense amplifier port and then amplifies it to a voltage level of the first and the second driving power supply voltage. A bit line separation unit(11,16) disconnects the positive/negative bit line sense amplifier port and the positive/negative bit line in response to a bit line separation signal. An equalization unit(10) maintains the potential of the positive/negative bit line equal in response to the first equalization signal. A precharge unit(12) precharges the positive/negative bit line sense amplifier port with a precharge voltage level in response to the second equalization signal. And the first and the second switching unit(30,31) disconnect the sense amplifier unit and the first and the second driving power supply voltage in response to a sense amplifier enable signal.