Reliable recalibration of DC head skew in hard disk drives

摘要

In hard disk drives (HDDs), head skew error among multiple heads is pre-calibrated during manufacturing process. Due to environmental change or non-operating shock, additional head skew errors across stroke may be resulted in. In this paper, a reliable recalibration strategy of DC head skew error during servo startup is proposed, where a sector-dependent head-switching scheme for avoidance of wrong calibration is developed. Test results demonstrate its effectiveness to enhance drive performance post non-operating shock.