公开(公告)号：US09721603B2

公开(公告)日：2017-08-01

申请号：US15237878

申请日：2016-08-16

Applicant: Seagate Technology LLC

Inventor： Daniel W. Olson ,  Declan Macken ,  Andrea L. Geer

IPC: G11B5/60

CPC classification number: G11B5/6011 ,  G11B5/6035 ,  G11B5/607 ,  G11B5/6076

Abstract: An apparatus comprises circuitry configured to apply an AC signal having a frequency to one of a slider of a recording head and a magnetic recording medium. The applied AC signal causes an oscillation in an electrostatic force and clearance between the slider and the medium at the frequency of the AC signal. A thermal sensor is configured to generate a sensor signal at the AC signal frequency in response to sensing changes in temperature resulting from the oscillating clearance. A detector is coupled to the circuitry and the thermal sensor. The detector is configured to detect one or both of head-medium spacing changes and head-medium contact using a phase of a first harmonic or an amplitude of a second harmonic of the thermal sensor signal.

公开(公告)号：US20170092313A1

公开(公告)日：2017-03-30

申请号：US15237878

申请日：2016-08-16

Applicant: Seagate Technology LLC

Inventor： Daniel W. Olson ,  Declan Macken ,  Andrea L. Geer

IPC: G11B5/60

CPC classification number: G11B5/6011 ,  G11B5/6035 ,  G11B5/607 ,  G11B5/6076

Abstract: An apparatus comprises circuitry configured to apply an AC signal having a frequency to one of a slider of a recording head and a magnetic recording medium. The applied AC signal causes an oscillation in an electrostatic force and clearance between the slider and the medium at the frequency of the AC signal. A thermal sensor is configured to generate a sensor signal at the AC signal frequency in response to sensing changes in temperature resulting from the oscillating clearance. A detector is coupled to the circuitry and the thermal sensor. The detector is configured to detect one or both of head-medium spacing changes and head-medium contact using a phase of a first harmonic or an amplitude of a second harmonic of the thermal sensor signal.