Abstract: A disk drive is disclosed wherein if a write command is aborted, the write command is re-executed according to a rotational position optimization (RPO) algorithm rather than immediately re-executing the write command to better optimize drive performance relative to mechanical latencies. An aborted write command is replaced into an input/output queue together with other pending commands. The aborted write command is eventually re-selected for execution by the RPO algorithm when executing the write command minimizes mechanical latencies relative to the other pending commands.

Abstract: The present invention may be embodied in a cache control method for caching disk data in a disk drive configured to receive commands for both streaming and non-streaming data from a host. A lossy state record is provided for memory segments in a cache memory. The lossy state record allows hosts commands to be mixed for streaming and non-streaming data without flushing of cache data for a command mode change.

Abstract: A disk drive is disclosed comprising a disk, a head, a voice coil motor (VCM) for actuating the head radially over the disk (the VCM having a voltage control input), and a spindle motor for rotating the disk, the spindle motor comprising a plurality of windings and a rotor rotatable at a variable spin rate wherein the rotor generates a back EMF (BEMF) voltage across the windings proportional to the spin rate of the rotor. A plurality of switching elements are coupled to the windings, and switch control logic generates switch control signals applied to the switching elements for commutating the spindle motor during normal operation and for generating an internal supply voltage Vi from the BEMF during a spin down mode, the internal supply voltage Vi applied to the voltage control input of the VCM for parking the head.

Abstract: A disk drive is disclosed comprising an actuator arm, a head coupled to the actuator arm, and a voice coil motor for actuating the actuator arm to move the head. The voice coil motor comprises a first magnet for generating a first magnetic flux, and a yoke comprising a magnetic flux conductor for guiding the first magnetic flux. The magnetic flux conductor comprises a body and a top and bottom protruding plate portions, wherein the body and the plate portions are integrally formed. The body defines, in vertical cross section, a primary bend having a primary bend radius and at least one secondary bend having a secondary bend radius.