| CPC G11C 16/08 (2013.01) [G11C 11/5642 (2013.01); G11C 16/0483 (2013.01); G11C 16/24 (2013.01); G11C 16/26 (2013.01); G11C 16/30 (2013.01); G11C 16/32 (2013.01); G11C 16/3427 (2013.01)] | 20 Claims |
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1. A semiconductor storage device, comprising:
a first memory cell electrically connected to a first bit line and a first word line;
a second memory cell electrically connected to a second bit line and a second word line;
a first circuit configured to supply voltages to the first word line; and
a second circuit configured to supply voltages to the second word line, wherein
during a first reading operation to read a first page of memory cells including the first memory cell, while the first memory cell is selected as a read target during a first time period, the first circuit supplies:
a first voltage to the first word line in an initial state during the first time period,
a second voltage that is greater than the first voltage to the first word line after supplying the first voltage,
a third voltage that is less than the second voltage to the first word line after supplying the second voltage,
a fourth voltage that is less than the second voltage to the first word line after supplying the third voltage,
a fifth voltage that is greater than the fourth voltage to the first word line after supplying the fourth voltage,
a sixth voltage that is greater than the fourth voltage to the first word line after supplying the fifth voltage; and
during a second reading operation to read a second page of memory cells including the second memory cell, while the second memory cell is selected as a read target during a second time period that is different from the first time period, the second circuit supplies:
a seventh voltage to the second word line in an initial state during the second time period,
an eighth voltage that is greater than the seventh voltage to the second word line after supplying the seventh voltage,
a ninth voltage that is less than the eighth voltage to the second word line after supplying the eighth voltage,
a tenth voltage that is less than the eighth voltage to the second word line after supplying the ninth voltage,
an eleventh voltage that is greater than the tenth voltage to the second word line after supplying the tenth voltage,
a twelfth voltage that is greater than the tenth voltage to the second word line after supplying the eleventh voltage;
the fourth voltage and the tenth voltage are each used as a first read voltage,
the fifth voltage is less than the eleventh voltage, and
the sixth voltage and the twelfth voltage are each used as a second read voltage.
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