Patent attributes
The present invention provides a data storage device including a flash memory and a controller. The controller distributes TLC-data blocks of the flash memory into three regions, obtains three sub-prewrite data sectors according to a prewrite data sector and a logic address, determines a first TLC-data block according to the logic address, selects a new first TLC-data block with the lowest erase count from the first region when the first TLC-data block has valid data, selects two TLC-data blocks according to the new first TLC-data block, writes the three sub-prewrite data sectors into the new first TLC-data block and the two selected TLC-data blocks, and maps the first new TLC-data block and the two selected TLC-data blocks to the logic address.