Data storage device and data maintenance method thereof

摘要

A data storage device including a flash memory and a controller. The controller performs a first read operation on the pages of a first block of a first block group, and performs a maintenance process to determine whether the first group read count of the first block group is greater than a read threshold when the first read operation is finished. The controller scans the blocks of the first block group to obtain a plurality of first error bit numbers when the first group read count is greater than the read threshold, and updates the block corresponding to the first error bit number that is greater than an error-bit threshold.

主权项

1. A data storage device, comprising:
a flash memory, having a plurality of block groups, wherein each of the block groups has a plurality of blocks, and each of the blocks has a plurality of pages; and a controller, configured to perform a first read operation on at least one first page of a first block which belongs to a first block group of the block groups, and perform a maintenance process in background after the first read operation is finished, wherein in the maintenance process:
the controller is configured to determine whether a first group read count of the first block group is greater than a read thresholdif yes, that is, if the first group read count is greater than the read threshold, the controller is configured to scan the pages of each of the blocks of the first block group to obtain a plurality of first error bit numbers corresponding to the blocks of the first block group, and update the block by moving the data store in the block corresponding to the first error bit number that is greater than an error-bit threshold, wherein the first group read count indicates a number of times that all of the pages have been read in the first block group, and the first error bit number indicates a number of error bits of the data stored in the block.