Technique for reassigning data sector by detecting soft defect

摘要

A data sector reassigning technique in a hard disk drive detects of a soft defect in a hard disk drive having a plurality of data sectors and an error correction capability. An error rate is calculated during a data read, and a soft defect is detected by varying the error correction capability according to the calculated error rate. A read error of the detected soft defect is recovered by setting the error correction capability to a maximum level if the read error is not recovered, and a spare sector is reassigned to substitute for a corresponding sector.