Patent ID: 9715341
Date: 2017-07-25
CPC Classifications: G06F,G11C

Claim:
1. A method of operating a memory system comprising a memory device, the method comprising: managing program order information of the memory device based on a program order stamp (POS) indicating a program order of program operations of a plurality of memory groups that are included in the memory device, wherein a POS is allocated to a memory group when a program operation is performed on the memory group, the POS being maintained until a next program operation is performed on the memory group; and controlling a read voltage for performing a read operation on the memory device, based on the program order information and a mapping table that stores a read voltage offset and a POS corresponding to the read voltage offset, wherein a value of the POS allocated to the memory group is changed when the next program operation is performed on the memory group, and wherein a POS of value 1 is allocated to a memory group from among the plurality of memory groups on which a program operation is firstly performed, a POS of value 2 is allocated to a memory group on which a program operation is secondly performed, and a POS of value n is allocated to a memory group on which a program operation is nthly performed, wherein n is an integer greater than 2.