Abstract: A data write method of a nonvolatile memory device is provided which includes receiving write data to be stored in selected memory cells; reading data stored in the selected memory cells; processing the write data according to a plurality of data modulation manners to generate a plurality of modulated data values; calculating the number of flip bits and the number of switching bits when the write data and the plurality of modulated data values are overwritten on the selected memory cells, each flip bit indicating that a logical value of a selected memory cell is reversed and each switching bit indicating that a logical value of a selected memory cell is switched from a first logical value to a second logical value; and selecting one of the write data and the plurality of modulated data values according to calculating the number of flip bits and the number of switching bits.

Abstract: Methods of operating nonvolatile memory devices including a plurality of cell strings each having at least one ground selection transistor, a plurality of memory cells, and at least one string selection transistor, the operating methods including receiving a command and an address, determining a voltage applying time in response to the input command and address, and applying a specific voltage to memory cells of cell strings corresponding to the input address during the determined voltage applying time.

Abstract: A method of operating a nonvolatile memory device configured to erase a memory block in sub-block units comprises detecting state information of unselected sub-blocks associated with a selected sub-block comprising selected memory cells, adjusting a read bias of the selected memory cells based on the state information, and reading data from the selected memory cells according to the adjusted read bias. The state information indicates a number of the unselected sub-blocks having a programmed state or an erased state.

Abstract: A method of operating a memory controller includes reading data from a first block of a memory device; detecting degraded pages from a plurality of pages of the first block and counting a number of the degraded pages in the first block; and recharging or reclaiming the first block, which includes the degraded pages, based on the counted number of the degraded pages.

Abstract: A nonvolatile memory device includes a memory block, a row decoder, a voltage generator and control logic. The memory block includes memory cells stacked in a direction intersecting a substrate, the memory block being divided into sub-blocks configured to be erased independently. The row decoder is configured to select the memory block by a sub-block unit. The voltage generator is configured to generate an erase word line voltage to be provided to a first word line of a selected sub-block of the sub-blocks and a cut-off voltage, higher than the erase word line voltage, to be provided to a second word line of the selected sub-block during an erase operation. The control logic is configured to control the row decoder and the voltage generator to perform an erase operation on the selected sub-block.

Abstract: An erase method of a nonvolatile memory device includes setting an erase mode, and performing one of a normal erase operation and a quick erase operation according to the set erase mode. The normal erase operation is performed to set a threshold voltage of a memory cell to an erase state which is lower than a first erase verification level. The quick erase operation is performed to set a threshold voltage of a memory cell to a pseudo erase state which is lower than a second erase verification level. The second erase verification level is higher than the first erase verification level.

Abstract: A solid state drive (SSD) includes non-volatile memory devices and a RAID controller. Each of the non-volatile memory devices includes a memory cell array having a plurality of physical pages. The RAID controller performs a parity operation on 1st through (N?1)th physical page data to generate Nth physical page data, determines a physical page group including 1st through Nth physical pages that are selected from the 1st through Nth non-volatile memory devices, respectively, such that at least two of the 1st through Nth physical pages have different bit error rates from each other, and stores the 1st through Nth physical page data in the 1st through Nth physical pages, respectively.

Abstract: In one embodiment, the method includes overwriting a memory cell storing m-bit data to store n-bit data, where n is less than or equal to m. The memory cell has one of a first plurality of program states when storing the m-bit data, and the memory cell has one of a second plurality of program states when storing the n-bit data. The second plurality of program states include at least one program state not in the first plurality of program states.

Abstract: A method of operating a memory controller includes reading data from a first block of a memory device; detecting degraded pages from a plurality of pages of the first block and counting a number of the degraded pages in the first block; and recharging or reclaiming the first block, which includes the degraded pages, based on the counted number of the degraded pages.

Abstract: Methods of operating nonvolatile memory devices including a plurality of cell strings each having at least one ground selection transistor, a plurality of memory cells, and at least one string selection transistor, the operating methods including receiving a command and an address, determining a voltage applying time in response to the input command and address, and applying a specific voltage to memory cells of cell strings corresponding to the input address during the determined voltage applying time.

Abstract: Example embodiments relate to a bad area managing method of a nonvolatile memory device. The nonvolatile memory device may include a plurality of memory blocks and each block may contain memory layers stacked on a substrate. According to example embodiments, a method includes accessing one of the memory blocks, judging whether the accessed memory block includes at least one memory layer containing a bad memory cell. If a bad memory cell is detected, the method may further include configuring the memory device to treat the at least one memory layer of the accessed memory block as a bad area.

Abstract: Disclosed is a memory system which includes a nonvolatile memory device including a memory cell array having a plurality of word lines including a first set of word lines storing first data having a high bit error rate, and a second set of word lines storing second data having low bit error rate less than the high bit error rate, and a memory controller that during a program operation maps logical addresses for a portion of the first data and a portion of the second data onto a selected word line selected from the plurality of word lines.