US 10,475,518 B2 · Memory system, memory system control method, and program

Abstract

According to one embodiment, a memory system comprises a nonvolatile memory, and a memory controller configured to manage a history value about setting of a read voltage in performing reading of data from the nonvolatile memory, in accordance with a first management unit and a second management unit, a size of the second management unit being smaller than a size of the first management unit. A first region of the nonvolatile memory corresponds to the first management unit. A plurality of second regions of the nonvolatile memory each correspond to the second management unit. The first region includes the plurality of second regions. The controller is configured to: obtain a first history value for the first region, and obtain a second history value for at least one of the second regions; and in execution of a read operation to a region included in the second regions, when the second history value for the region included in the second regions is not obtained, execute the read operation to the region included in the second regions by using the first history value obtained for the first region.

Claims20

Dependent claims

A memory system comprising:

a nonvolatile memory;
and
a memory controller configured to manage a history value about setting of a read voltage in performing reading of data from the nonvolatile memory, in accordance with a first management unit and a second management unit, a size of the second management unit being smaller than a size of the first management unit,
wherein
a first region of the nonvolatile memory corresponds to the first management unit,
a plurality of second regions of the nonvolatile memory each correspond to the second management unit,
the first region includes the plurality of second regions, and
the controller is configured to:
obtain a first history value for the first region, and obtain a second history value for at least one of the second regions;
and
in execution of a read operation to a region included in the second regions, when the second history value for the region included in the second regions is not obtained, execute the read operation to the region included in the second regions by using the first history value obtained for the first region.

8 more elements

A method of controlling a memory system including a nonvolatile memory and a memory controller configured to manage a history value about setting of a read voltage in performing reading of data from the nonvolatile memory, in accordance with a first management unit and a second management unit, a size of the second management unit being smaller than a size of the first management unit, a first region of the nonvolatile memory corresponding to the first management unit, a plurality of second regions of the nonvolatile memory each corresponding to the second management unit, the first region including the plurality of second regions, said method comprising:

obtaining a first history value for the first region;
obtaining a second history value for at least one of the second regions;
and
in execution of a read operation to a region included in the second regions, when the second history value for the region included in the second regions is not obtained, executing the read operation to the region included in the second regions by using the first history value obtained for the first region.

1 more element

Dependencies are inferred from the claim text.

Memory system, memory system control method, and program

Life of this patent

Memory system, memory system control method, and program

Life of this patent

Abstract

Claims20