Patent ID: 7982987

Claim:
A method of characterizing a hard disk drive, the hard disk drive comprising a magnetic disk and a head slider comprising read and write elements and a thermal fly-height control for adjusting a clearance between the head slider and the magnetic disk, the method comprising: applying a varying control signal to the fly-height control to adjust the clearance between the head slider and the magnetic disk; wherein the fly-height control is a heating element embedded in the head slider, and the control signal to the fly-height control comprises power supplied to the heating element; measuring an output of the read element as the control signal is varied; determining if a touch-down between the head slider and the magnetic disk has occurred based on the measured output of the read element; and characterizing the hard disk drive based on the varied control signal to the fly-height control, and on whether a touch-down has occurred; wherein characterizing the hard disk drive comprises determining that the power supplied to the heating element is above a predetermined value when it is determined that a touch-down between the head slider and the magnetic disk has not occurred.