Abstract: A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a spin torque oscillator (STO). A first bias signal is applied to the STO during a first interval preceding a write operation to write data to the disk, wherein the first bias signal causes the STO to protrude toward the disk. After the first interval, a second bias signal is applied to the STO during a second interval spanning at least part of the write operation, wherein an amplitude of the first bias signal is in the range of 1.1 to 1.5 times an amplitude of the second bias signal.

Abstract: A method is disclosed for selecting a global digital-to-analog setting for a plurality of heads in a disk drive, the disk drive comprising a plurality of disk surfaces and a plurality of respective heads. The method comprises: adjusting a first digital-to-analog setting for a first head to generate a first signal, adjusting a second digital-to-analog setting for a second head to generate a second signal, selecting a first scalar setting for scaling the first signal, selecting a second scalar setting for scaling the second signal, and selecting the global digital-to-analog setting in response to the adjusted first digital-to-analog setting, the adjusted second digital-to-analog setting, the first scalar setting, and the second scalar setting.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, and a fly height actuator operable to control a fly height of the head over the disk. A periodic control signal is applied to the fly height actuator, a frequency response of a touchdown metric at a frequency of the periodic control signal is measured, and a touchdown event is detected in response to the frequency response of the touchdown metric.