| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor memory device which assures higher read operation rate without deteriorating low voltage characteristic, low power consumption property and reduction in size. SOLUTION: In a semiconductor memory device which functions as a DRAM comprising a memory cell array in which the memory cells 9 are provided in the form of matrix, word lines 7 for connecting the memory cells 9 in the row direction and bit lines 8 for connecting memory cells 9 in the column direction, the power supply voltage switching circuits 1A, 1B, 1C are provided for the sense amplifier drive circuits 4A, 4B, 4C arranged along the direction of bit line 8 in order to switch the power supply voltage of the sense amplifier 5 to the external power supply VDD from the internal voltage drop power supply VINT while the readout data is amplified with the sense amplifier 5 in the selecting operation of the memory cell 9. Thereby, charges are supplied via the sense amplifier drive circuit and the number of sense amplifiers which operate simultaneously can be reduced and thereby data amplifying rate becomes high. |
