Abstract: A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

Abstract: A storage device includes a first interconnection, a second interconnection, a memory cell connected between the first and second interconnections and including a variable resistance element and a switching element that is connected in series to the variable resistance element, and a control circuit configured to exercise control of a read operation to read data stored in the memory cell. The control circuit exercises control in such a manner as to set the first interconnection which has been charged with a first voltage and the second interconnection which has been charged with a second voltage into floating states, to set the switching element into an on-state by discharging the second interconnection set into the floating state to thereby increase a voltage applied to the memory cell, and to read the data stored in the memory cell in a state in which the switching element is set into the on-state.

Abstract: A memory system according to an embodiment includes a plurality of first wirings, a plurality of second wirings, a memory cell, a third wiring, a sense amplifier, a first switching element, a first transistor including a first terminal connected to a first node and a second terminal connected to a second node, and a control circuit. The first node is positioned further to the side of the sense amplifier than the first switching element. The second node is positioned further to the memory cell than the first switching element. The control circuit is configured to connect the first node and the second node when the first switching element is in an ON state, and connect the first node and the gate terminal of the first transistor when the first switching element is in an OFF state.

Abstract: A memory system includes a non-volatile memory and a memory controller configured to receive a command including an access target in the non-volatile memory and setting information from an external device and configured to control a writing operation or a reading operation to the access target. The memory controller has a condition setting circuit. The condition setting circuit is capable of performing the writing operation or the reading operation under a plurality of different conditions. The memory controller performs the writing operation or the reading operation under one of the plurality of different conditions selected by the condition setting circuit in accordance with the setting information.

Abstract: A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

Abstract: A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit in which data is managed in a predetermined unit, and a controller that writes data requested by a host apparatus in the second storing unit via the first storing unit and reads out data requested by the host apparatus from the second storing unit to the first storing unit and transfers the data to the host apparatus. The controller includes a management table for managing the number of failure areas in a predetermined unit that occur in the second storing unit and switches, according to the number of failure areas, an operation mode in writing data in the second storing unit from the host apparatus.

Abstract: A first memory cell is coupled to first and third interconnects. A second memory cell is coupled to second and fourth interconnects. A first sense amplifier has a first terminal coupled to the first interconnect and a node of a first potential and a second terminal located close to a node of a second potential and coupled to the third interconnect and has a potential difference between the first and second terminals. A second sense amplifier has a third terminal coupled to the fourth interconnect and a node of a third potential and a fourth terminal located close to a node of a fourth potential and coupled to the second interconnect and has a potential difference between the third and fourth terminals.

Abstract: In a memory, a first node holds first data from a first cell. A second node holds second data from a second cell near the first cell. A differential circuit includes a first current path passing a first current corresponding to a voltage of the first node and a second current path passing a second current corresponding to a voltage of the second node, and outputs an output signal corresponding to a voltage difference between the first and the second nodes from an output part. A first register latches the output signal and output the signal as a hold signal. A first offset part is connected to the first current path and offsets the first current when the hold signal has a first logic level. A second offset part is connected to the second current path and offsets the second current when the hold signal has a second logic level.

Abstract: According to one embodiment, a memory device includes first and second wiring lines, memory cells between first and second wiring lines, first and second common wiring lines, a first selecting circuit between one ends of the first wiring lines and the first common wiring line, and a second selecting circuit between the other ends of the first wiring lines and the first common wiring line. A path between the first wiring line and the first common wiring line through the first selecting circuit and a path between the first wiring line and the first common wiring line through the second selecting circuit are defined as first and second paths, one of the first and second paths is set to an electrically conductive state.

Abstract: A storage device includes a first interconnection, a second interconnection, a memory cell connected between the first and second interconnections and including a variable resistance element and a switching element that is connected in series to the variable resistance element, and a control circuit configured to exercise control of a read operation to read data stored in the memory cell. The control circuit exercises control in such a manner as to set the first interconnection which has been charged with a first voltage and the second interconnection which has been charged with a second voltage into floating states, to set the switching element into an on-state by discharging the second interconnection set into the floating state to thereby increase a voltage applied to the memory cell, and to read the data stored in the memory cell in a state in which the switching element is set into the on-state.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit in which data is managed in a predetermined unit, and a controller that writes data requested by a host apparatus in the second storing unit via the first storing unit and reads out data requested by the host apparatus from the second storing unit to the first storing unit and transfers the data to the host apparatus. The controller includes a management table for managing the number of failure areas in a predetermined unit that occur in the second storing unit and switches, according to the number of failure areas, an operation mode in writing data in the second storing unit from the host apparatus.

Abstract: According to one embodiment, a memory device includes first and second wiring lines, a memory cell connected between the first and second wiring lines and including a resistance change memory element and a switching element connected in series to the resistance change memory element, and a determination circuit determining a determination object resistance state set in advance to the resistance change memory element based on a determination object voltage applied to the second wiring line when the switching element makes a transition from an on-state to an off-state.

Abstract: According to one embodiment, a magnetic storage device includes a magnetoresistive element having a first end and a second end. A first switch is between the first end and a first wiring. A second switch is between the second end and a second wiring. A third switch is between the first end and a third wiring. A fourth switch is between the second end and a fourth wiring. A driver is connected to the first wiring and the second wiring and is configured to supply, to the first wiring, a current at a magnitude set based on a voltage at the first end and a voltage at the second end.

Abstract: In a memory, a first node holds first data from a first cell. A second node holds second data from a second cell near the first cell. A differential circuit includes a first current path passing a first current corresponding to a voltage of the first node and a second current path passing a second current corresponding to a voltage of the second node, and outputs an output signal corresponding to a voltage difference between the first and the second nodes from an output part. A first register latches the output signal and output the signal as a hold signal. A first offset part is connected to the first current path and offsets the first current when the hold signal has a first logic level. A second offset part is connected to the second current path and offsets the second current when the hold signal has a second logic level.

Abstract: A first memory cell is coupled to first and third interconnects. A second memory cell is coupled to second. and fourth interconnects first sense amplifier has a first terminal coupled to the first interconnect and a node of a first potential and a second terminal located close to a node of a second potential and coupled to the third interconnect and has a potential difference between the first and second terminals. A second sense amplifier has a third terminal coupled to the fourth interconnect and a node of a third potential and a fourth terminal located close to a node of a fourth potential and coupled to the second interconnect and has a potential difference between the third and fourth terminals.

Abstract: According to one embodiment, a magnetic storage device includes a magnetoresistive element having a first end and a second end. A first switch is between the first end and a first wiring. A second switch is between the second end and a second wiring. A third switch is between the first end and a third wiring. A fourth switch is between the second end and a fourth wiring. A driver is connected to the first wiring and the second wiring and is configured to supply, to the first wiring, a current at a magnitude set based on a voltage at the first end and a voltage at the second end.

Abstract: According to one embodiment, a memory device includes first and second wiring lines, memory cells between first and second wiring lines, first and second common wiring lines, a first selecting circuit between one ends of the first wiring lines and the first common wiring line, and a second selecting circuit between the other ends of the first wiring lines and the first common wiring line. A path between the first wiring line and the first common wiring line through the first selecting circuit and a path between the first wiring line and the first common wiring line through the second selecting circuit are defined as first and second paths, one of the first and second paths is set to an electrically conductive state.

Abstract: A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

Abstract: According to one embodiment, a memory device includes: a first and a second interconnects; a memory cell including a variable resistive element, the memory cell between the first and second interconnects; and a write circuit including a current source circuit and a voltage source circuit, the write circuit writing data to the memory cell by using a write pulse. The write circuit supplies the write pulse to the memory cell by using the current source circuit in a first period from a first time of a start of supply of the write pulse to a second time, and supplies the write pulse to the memory cell by using the voltage source circuit in a second period from a third time to a fourth time of an end of the supply of the write pulse.