Semiconductor memory device
AssigneeKabushiki Kaisha Toshiba
InventorsTakayuki Otani, Yasumitsu Nozawa, Satoru Hoshi
Life of this patent
Estimating the term…
Loading patent…
AssigneeKabushiki Kaisha Toshiba
InventorsTakayuki Otani, Yasumitsu Nozawa, Satoru Hoshi
Estimating the term…
A semiconductor memory device includes normal row selection lines (NWL1 to NWL128) for selecting one of normal rows, a spare row selection line (SWL) for selecting a spare row instead when one of the normal rows has a defect, fuses (F1 to F128) which are respectively arranged on the normal row selection lines, and blown when a defect exists, a normal row non-selection circuit (inverters IN3 and IN6 and gate G3) when one of the fuses (F1 to F128) is blown, setting a corresponding normal row in a non-selected state, and a spare row selection circuit (gates G4, G5, and G6, transistors P2 and N1, a NOR gate NR1, and an inverter IN6) selecting the spare row instead of the defective normal row. The spare row selection circuit performs dynamic operation in synchronism with a clock (ck). In this manner, control of, when a defect exists in a normal row or column, switching the defective row or column to a spare row or column is performed by dynamic operation in synchronism with an internal clock, thereby increasing the access speed.
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal rows and one spare row, and selects a row using a clock signal, said each block comprising:
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal rows and one spare row, and selects a row using a clock signal, said each block comprising:
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal rows and one spare row, and selects a row using a clock signal, said each block comprising:
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal columns and one spare column, and selects a column using a clock signal, said each block comprising:
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal columns and one spare column, and selects a column using a clock signal, said each block comprising:
A semiconductor memory device which has at least one block in which memory cells are respectively arranged on a plurality of normal columns and one spare column, and selects a column using a clock signal, said each block comprising:
Dependencies are inferred from the claim text.