Various illustrative aspects are directed to a data storage device. The data storage device comprises a first actuator; a second actuator; a first set of disks, comprising one or more disks configured to correspond with the first actuator; a second set of disks, comprising one or more disks configured to correspond with the second actuator; and one or more processing devices. The one or more processing devices are configured to: write final spirals on the first set of disks; determine a time delta to implement cross-actuator alignment between the first set of disks and the second set of disks; and apply the time delta in writing final spirals for the second set of disks.

A motor driver circuit includes: a current detection circuit configured to generate a current detection signal according to a drive current of a motor as an object to be driven; a first amplifier configured to amplify the current detection signal; a second amplifier configured to multiply a voltage across the motor by a gain smaller than 1 and output the multiplied voltage; and a third amplifier configured to generate a back electromotive force detection signal according to a difference between an output of the first amplifier and an output of the second amplifier.

A voice coil motor yoke having a magnet bonding surface includes an annular groove inside a bonding region on the magnet bonding surface, the bonding region having substantially the same shape as a contour of a magnet to be bonded on the magnet bonding surface of the yoke. A region surrounded by the annular groove on the magnet bonding surface is an adhesive application region. A voice coil motor includes: a pair of the voice coil motor yokes; an adhesive applied to the adhesive application region of each of the pair of yokes; and a pair of rare earth magnets bonded via the adhesive to the bonding region of each of the pair of yokes.

A tolerance ring includes a base formed of a strip-like member approximately wound around into a ring shape, and a plurality of projections provided along a winding direction of the base so as to protrude in a radial direction from an outer peripheral surface of the base, wherein each of the projections has edges serving as a boundary with the base and at least one of the edges in a width direction orthogonal to the winding direction has a shape intersecting the winding direction.

A data storage device includes a ferromagnetic center pole, a drive coil for an actuator arm assembly, and a magnetic assembly surrounding the drive coil. The drive coil surrounds the center pole and has a top, a bottom, and first and second sides; the first side is attached to the actuator arm assembly. The magnetic assembly includes a top magnet disposed above and spaced from the center pole, a bottom magnet disposed below and spaced from the center pole, and a side magnet disposed proximate the second side of the coil and spaced from the center pole. In another embodiment, a linear actuator comprises a ferromagnetic center pole, a drive coil supported for linear motion on a rail, and a magnetic assembly. A method including linearly moving a drive coil along a center pole by a magnetic field is also described.

A data storage device is disclosed comprising a plurality of disks each comprising a top disk surface and a bottom disk surface, and a plurality of actuator arms each comprising a first fine actuator configured to actuate a top head over one of the top disk surfaces and a second fine actuator configured to actuate a bottom head over one of the bottom disk surfaces. A first fine driver controls the fine actuators of an even interleave of the actuator arms, and a second fine driver controls the fine actuators of an odd interleave of the actuator arms.

Disclosed herein is a motor driver circuit including a first output terminal to be connected to a first end of a to-be-driven motor via a sense resistor, a second output terminal to be connected to a second end of the motor, an error detector that generates an error signal, an A/D converter that obtains a digital signal, a compensator that generates a voltage command value, a D/A converter that converts the voltage command value to an analog control signal, a pulse width modulator that generates a first pulse and a second pulse, and an output stage that generates a first driving voltage and a second driving voltage. During a first mode, the compensator uses the error signal obtained by the A/D converter at a negative edge timing of the first pulse, for the error signal at a positive edge timing of the second pulse.

The presently disclosed technology is directed to maximizing cleanliness, reliability, and space efficiency within a jukebox-style HDD, while minimizing overall cost of the HDD. In an effort to reduce the movement of a robotic arm assembly, cassettes within a jukebox-style HDD may be configured to be magnetically repositionable to replace some of the movement of the robotic arm assembly, without adding another significant source of potential mechanical failure within the HDD enclosure. Further, the overall number of moving parts is reduced, which may improve reliability of the HDD, as well as cleanliness within the HDD enclosure.

According to one embodiment, a magnetic disk device which includes two or more independently drivable actuator blocks and performs seek control with a low jerk in which a jerk that is a derivative of acceleration is limited, wherein in a state where a first actuator block is not accessing a data sector of a disk, a second actuator block that is not the first actuator block accesses the data sector of the disk by seek control with a high Jerk.

The presently disclosed technology is directed to maximizing cleanliness, reliability, and space efficiency within a jukebox-style HDD, while minimizing overall cost of the HDD. In an effort to reduce the movement of a robotic arm assembly, cassettes within a jukebox-style HDD may be configured to be magnetically repositionable to replace some of the movement of the robotic arm assembly, without adding another significant source of potential mechanical failure within the HDD enclosure. Further, the overall number of moving parts is reduced, which may improve reliability of the HDD, as well as cleanliness within the HDD enclosure.