US Patent 10096357 Data storage device and data writing method thereof

The present invention provides a data storage device including a flash memory and a controller. The controller checks whether a first number of a first page in the flash memory is greater than a predetermined threshold when the data storage device resumes operation after a power-off event, and stops writing data into a first TLC block when the first number of the first page is greater than the predetermined threshold, wherein the first TLC block was undergoing a first write operation which was unfinished when the power-off event occurred, and the first page was the last one being written in the first TLC block.