Patent ID: 7779341

Claim:
A NAND flash memory device configured to perform a program operation, and a copy back program operation, the memory device comprising: a cell array comprising a plurality of planes, wherein each plane is configured to store program data; a parity cell array comprising a plurality of parity planes, wherein each parity plane is configured to store parity data associated with program data stored in a corresponding one of the plurality of planes; a column selection and parity generation circuit configured to receive the program data during the program operation; a page buffer configured to receive the program data from the column selection and parity generation circuit during the program operation, and further configured to receive source page data from a source page of the cell array during the copy back program operation; a parity page buffer configured to receive source page parity data from a source parity page of the parity cell array corresponding to the source page during the copy back program operation; and a parity generation and parity column selection circuit, wherein the column selection and parity generation circuit and the parity generation and parity column selection circuit are configured to cooperatively detect an error in the source page data during the copy back program operation, the column selection and parity generation circuit is further configured to reload the source page data upon detection of the error in the source page data to a selected plane in the cell array, and the parity generation and parity column selection circuit is configured to generate new source page parity data for the reloaded source page data and program the new source page parity data in a selected parity plane corresponding to the selected plane storing the reloaded source page data.