Disk drive to reduce head instability
AssigneeWestern Digital Technology, Inc.
InventorsJianfeng Xu, Soo-Choon Kang, Kazuhiro Saito, Hongchao Tim Zhao
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Abstract
A disk drive to reduce head instability during disk drive manufacturing is disclosed. The disk drive comprises: a disk; a dynamic flying height (DFH) read/write head; a flying height actuator to control the spacing between the DFH read/write head and the disk; and a controller. The controller controls operations in the disk drive including applying a sloped increasing power between a first voltage and a second voltage to move the DFH read/write head towards the disk.
Claims16
A disk drive to reduce head instability during disk drive manufacturing, the disk drive comprising:
- a disk;
- a dynamic flying height (DFH) read/write head;
- a flying height actuator to control the spacing between the DFH read/write head and the disk;
- a touch distance sensor to measure a spacing signal between the DFH read/write head and the disk;
- and
- a controller for controlling operations in the disk drive including:
- applying a sloped increasing power between a first voltage and a second voltage to move the DFH read/write head towards the disk;
- receiving the spacing signal from the touch distance sensor;
- determining if the DFH head is approaching touchdown based on the spacing signal, and if not, applying a second sloped increasing power between the second voltage and a third voltage;
- wherein, if at the third voltage, the DFH head is determined to be approaching touchdown based upon the spacing signal, a touchdown calibration value for the DFH read/write head to avoid head-disk interaction is set at the second voltage.
A method to reduce head instability during disk drive manufacturing, the method comprising:
- controlling the spacing between a dynamic flying height (DFH) read/write head and a disk;
- measuring a spacing signal between the DFH read/write head and the disk from a touch distance sensor;
- applying a sloped increasing power between a first voltage and a second voltage to the DFH read/write head to move the DFH read/write head towards the disk;
- determining if the DFH head is approaching touchdown based on the spacing signal, and if not,
- applying a second sloped increasing power between the second voltage and a third voltage, wherein, if at the third voltage, the DFH head is determined to be approaching touchdown based upon the spacing signal, a touchdown calibration value for the DFH read/write head to avoid head-disk interaction is set at the second voltage.
Dependencies are inferred from the claim text.