摘要:
The flash memory device includes a control logic circuit and a bit level conversion logic circuit. The control logic circuit programs first through Nth bits of data in a memory cell array of the N-bit MLC flash memory device or reads the first through Nth bits of the data from the memory cell array in response to one of a program command and a read command. The bit level conversion control logic circuit, after the first through Nth bits of the data are completely programmed or read, programs or reads an (N+1)th bit of the data in response to a control signal. The bit level conversion control logic circuit converts voltage levels of voltages, which are used for programming or reading the first through Nth bits of the data, to program or read for 2N cell distributions of 2N+1 cell distributions corresponding to the (N+1)th bit of the data and then programs or reads for other 2N cell distributions.
摘要:
A nonvolatile memory device comprises a memory controller having a memory cell status estimator that generates status estimation information indicating the status of a memory cell based on status register data, a coupling group index selector configured to generate a select signal for selecting a page and coupling group index from the status estimation information, and a memory cell status value generator configured to map the status estimation information to the data reliability decision bits and the coupling group index and generate a status value of the memory cell for error correction code decoding.
摘要:
A method of reading data in a non-volatile memory device. The method includes reading a plurality of memory cells of a first page in a memory cell array using a first read level, reading a plurality of memory cells of a second page adjacent to the memory cells of the first page using a second read level, determining whether a state of each memory cell of the first page has been changed based on the first read level to verify a threshold voltage of each memory cell of the second page based on the second read level, and revising the state of each memory cell of the second page according to a result of the determination.
摘要:
A nonvolatile memory device comprises a memory controller having a memory cell status estimator that generates status estimation information indicating the status of a memory cell based on status register data, a coupling group index selector configured to generate a select signal for selecting a page and coupling group index from the status estimation information, and a memory cell status value generator configured to map the status estimation information to the data reliability decision bits and the coupling group index and generate a status value of the memory cell for error correction code decoding.
摘要:
A nonvolatile memory device using interleaving technology is provided. The nonvolatile memory device includes a first controller configured to allocate one of 2N threshold voltage states to N-bit data where N is 2 or a natural number greater than 2, a second controller configured to set a difference between adjacent threshold voltage states among the 2N threshold voltage states so that the difference increases as a threshold voltage increases, and a programming unit configured to form a threshold voltage distribution state corresponding to the allocated threshold voltage state and to program the N-bit data to a multi-level cell. The second controller controls the difference between the adjacent threshold voltage states to equalize the number of read errors for all intersections among the 2N threshold voltage states at the end of life.
摘要:
A method of reading data in a non-volatile memory device. The method includes reading a plurality of memory cells of a first page in a memory cell array using a first read level, reading a plurality of memory cells of a second page adjacent to the memory cells of the first page using a second read level, determining whether a state of each memory cell of the first page has been changed based on the first read level to verify a threshold voltage of each memory cell of the second page based on the second read level, and revising the state of each memory cell of the second page according to a result of the determination.
摘要:
A method of estimating a read level for a memory device includes calculating first information corresponding to at least one among information about the number of cells having a particular logic level in data to be programmed and information about the number of cells having a particular cell state and storing the first information during a program operation; reading the data based on a threshold level that has been set and calculating second information about the number of cells in at least one state defined by the threshold level with respect to the read data; calculating third information about the number of cells in the at least one state, which corresponds to the second information, using a probability based on the first information; comparing the second information with the third information; and determining whether to change the threshold level according to the comparison result.
摘要:
A nonvolatile memory device using interleaving technology is provided. The nonvolatile memory device includes a first controller configured to allocate one of 2N threshold voltage states to N-bit data where N is 2 or a natural number greater than 2, a second controller configured to set a difference between adjacent threshold voltage states among the 2N threshold voltage states so that the difference increases as a threshold voltage increases, and a programming unit configured to form a threshold voltage distribution state corresponding to the allocated threshold voltage state and to program the N-bit data to a multi-level cell. The second controller controls the difference between the adjacent threshold voltage states to equalize the number of read errors for all intersections among the 2N threshold voltage states at the end of life.
摘要:
A method of reading a nonvolatile memory device comprises measuring threshold voltage distributions of a plurality of memory cells, combining the measured threshold voltage distributions, and determining local minimum points in the combined threshold voltage distributions to determine read voltages for a predetermined group of memory cells.
摘要:
A reading method of a flash memory, the reading method including: sensing hard data of a first target page by using a first hard read voltage; and generating soft data of the first target page by using at least one pair of, that is, two, first soft read voltages whose voltage levels are different from a voltage level of the first hard read voltage, while the flash memory performs a first operation on the hard data.