Memory system using non-linear filtering scheme and read method thereof
AssigneeSamsung Electronics Co., Lto.
InventorsDONGSUP JIN, PILSANG YOON, HONG RAK SON, JUNJIN KONG, YOUNG-SEOP SHIM, JINMAN HAN
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Abstract
A method for controlling a nonvolatile memory device includes requesting a plurality of first sampling values from the nonvolatile memory device, each of the first sampling values representing the number of memory cells having a threshold voltage between a first sampling read voltage and a second sampling read voltage. The first sampling values are processed through a non-linear filtering operation to estimate the number of memory cells having the threshold voltage between the first sampling read voltage and the second sampling read voltage.
Claims35
A non-volatile memory system comprising:
- a nonvolatile memory device comprising a plurality of memory cells, where each memory cell comprises a plurality memory blocks and each memory block comprises a plurality of pages;
- and
- a memory controller configured to apply a read voltage at a first read level to read data from selected memory cells among the plurality of memory cells, transfer a command to the nonvolatile memory device to request a plurality of sampling values for a specific voltage range when the apply results in a read failure, receive the sampling values from the nonvolatile memory device in response the command, apply non-linear filtering to the received sampling values to generate filtered values, and set the read voltage to a second read level based on the filtered values,
- wherein each of the filtered values indicates a number of the selected memory cells having a threshold voltage at the specific voltage range.
A method for controlling a non-volatile memory device comprising a plurality of memory cells and a memory controller, where each memory cell comprises a plurality of memory blocks and each memory block comprises a plurality of pages, the method comprising:
- applying, by the memory controller, a read voltage at a first read level to read data from selected memory cells among the plurality of memory cells;
- transferring, by the memory controller, a command to the nonvolatile memory device to request a plurality of sampling values for a specific voltage range when the applying results in a read failure;
- receiving, by the memory controller, sampling values from the nonvolatile memory device in response to the command;
- applying, by the memory controller, non-linear filtering to the sampling values to generate filtered values;
- and
- setting, by the memory controller, the read voltage to a second read level based on the filtered values,
- wherein each of the filtered values indicates a number of the selected memory cells having a threshold voltage at the specific voltage range.
A non-volatile memory system comprising:
- a nonvolatile memory device comprising a plurality of memory cells, where each memory cell comprises a plurality memory blocks and each memory block comprises a plurality of pages;
- and
- a memory controller configured to apply a read voltage at a first read level to read data from selected memory cells among the plurality of memory cells, transfer a command to the nonvolatile memory device to request a plurality of sampling values for a specific voltage range when the apply results in a read failure, receive the sampling values from the nonvolatile memory device in response the command, discard the sampling values having corresponding voltages outside a threshold range of a threshold voltage distribution of the selected memory cells, and set the read voltage to a second read level based on the remaining sampling values,
- wherein each of the remaining sampling values indicates a number of the selected memory cells having a threshold voltage at the specific voltage range.
A method for controlling a non-volatile memory device comprising a plurality of memory cells and a memory controller, where each memory cell comprises a plurality of memory blocks and each memory block comprises a plurality of pages, the method comprising:
- applying, by the memory controller, a read voltage at a first read level to read data from selected memory cells among the plurality of memory cells;
- transferring, by the memory controller, a command to the nonvolatile memory device to request a plurality of sampling values for a specific voltage range when the applying results in a read failure;
- receiving, by the memory controller, sampling values from the nonvolatile memory device in response to the command;
- discarding, by the memory controller, the sampling values having corresponding voltages outside a threshold range of a threshold voltage distribution of the selected memory cells;
- and
- setting, by the memory controller, the read voltage to a second read level based on the remaining sampling values,
- wherein each of the remaining values indicates a number of the selected memory cells having a threshold voltage at the specific voltage range.
Dependencies are inferred from the claim text.