Abstract: Systems and methods for reducing problems and disadvantages associated with protecting data during cold excursions are provided. A method for preventing unreliable data operations at cold temperatures may include determining whether a first internal temperature of a hard disk drive (HDD) is below a threshold temperature. The method may also include initiating an artificial seek operation if the first internal temperature is below the threshold temperature.

Abstract: The disclosure is related to an apparatus and methods of suppressing seek repeatable runout. In a particular embodiment, a servo loop is disclosed. The servo loop includes a seek signal generation component that generates a seek trajectory acceleration signal. The servo loop also includes a STRRO suppression component that is coupled to the seek signal generation component. The STRRO suppression component injects STRRO suppression signals into the seek trajectory acceleration signal and outputs an STRRO suppressed seek trajectory acceleration signal.

Abstract: The disclosure is related to systems and methods for adaptive seek latency in a rotating storage device. In one example, a servo control circuit can be configured to determine a seek latency and provide the seek latency to another controller or control circuit that is configured to implement the seek latency. Further, the servo control circuit can calculate the seek latency based on a measurement of a variable condition of a device and the servo controller can adjust the seek latency as the condition varies. In some examples, the variable condition may include power measurements, temperature measurements, a fault rate, other conditions, or any combination thereof. Also, different algorithms for calculating the seek latency may be implemented based on a selected goal of the system, such as power savings or reduced head vibration.

Abstract: The invention is a patterned-media disks for multi-track recording that are fabricated by nanoimprinting from a master template and that have data islands arranged in a pattern to compensate for head skew. The islands are arranged along lines canted relative to a disk radial line by an acute angle, as required for multi-track recording. However, this angle is not the same for all bands, but varies from band to band to compensate for head skew. The angle the lines in a band are canted is reduced by the amount of head skew. There are a plurality of bands between the disk inside-diameter (ID) and mid-diameter (MD) where the angle is in one direction from a radial line and a plurality of bands between the disk MD and outside-diameter (OD) where the angle is in the opposite direction from a radial line.

Abstract: A disk drive is disclosed comprising a disk including a plurality of servo tracks, wherein each servo track comprises a plurality of servo sectors. The disk drive further comprises an actuator for actuating a head over the disk in response to an actuator control signal. The servo sectors are read to generate a first sequence of control samples x[k] at a sample rate corresponding to a frequency of the servo sectors. The first sequence of control samples x[k] is upsampled by a factor of N to generate a second sequence of control samples y[ki] according to: y ? [ k i ? | i = 1 : N ] = ( 1 - i N - ? ) ? u ? [ k - 1 ] + ( i N + ? ) ? u ? [ k ] where ? is a scalar greater than or equal to zero and less than one. The actuator control signal is generated in response to the second sequence of control samples y[ki].

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of tracks, and control circuitry operable to seek the head to a target track and settle the head on the target track during a settle time, adapt a settle parameter used to settle the head on the target track, access the target track after an access delay, and decrease the access delay based on a speed that the settle parameter adapts.

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of data tracks, wherein the head comprises a write element and a read element. An asperity in a target data track is detected, and a range of data tracks proximate the target data track is mapped out, wherein the range of data tracks spans at least twice a radial offset between the read element and the write element at the radial location of the target data track.

Abstract: A ramp-unloading seek control device includes a voice coil motor, a detector, an instruction-current detector, a head-speed computing unit, and an identification structure. The identification structure estimates an error between a true resistance value and an estimated resistance value of the voice coil motor. The identification structure can minimize an estimated error defined as a difference between an estimated value ?(k) of the head speed and the head speed y(k), and employs {circumflex over (b)}1 to calibrate the estimated error. {circumflex over (b)}1 is determined by minimizing the estimated error. ?(k) and y(k) are defined by the equation (A): ?(k)=?â1y(k?1)+{circumflex over (b)}0u(k?1)+{circumflex over (b)}1u(k?2)??(A). y(k?1) denotes a head speed computed by the head-speed computing unit at the last sampling time. k denotes the present sampling time. u(k?1) and u(k?2) denote instruction currents at the last sampling time and the last but one sampling time, respectively.

Abstract: A magnet of rectangular prism of parallelepiped prism shape is disposed on a yoke having a triangle shape or a frusto-triangular shape to construct a magnetic circuit for a voice coil motor. The magnetic circuits facilitate positioning and holding of a moving coil, and the voice coil motor is improved in positioning precision of a magnetic head.

Abstract: An object of the present invention is to further improve a recording density in a magnetic disk apparatus using a shingle write system. In a magnetic disk apparatus including a magnetic disk, a recording head that writes information on the magnetic disk, and a controller that controls a writing operation of the recording head to the magnetic disk, the controller controls the writing operation such that the recording head writes information on a region including a target track and a portion of track adjacent thereto in an overlapping manner while position-shifting in a radial direction of the magnetic disk and a first writing frequency to a track on which information is last written is higher than a second writing frequency to another track.

Abstract: According to one embodiment, there is provided a magnetic recording apparatus including a bit-patterned medium having a data area including magnetic dot rows each of which includes magnetic dots, a magnetic head having a width covering a plurality of magnetic dot rows, and an actuator configured to actuate the magnetic head in a cross-track direction. The magnetic dots included in a n-th magnetic dot row have a higher coercivity than the magnetic dots included in a (n+1)-th magnetic dot row.

Abstract: According to one embodiment, a servo area of a magnetic recording medium includes magnetic dots arrayed at a period L0. The magnetic dots include a plurality of magnetic dot regions divided in the cross track direction. A width Wm in the down track direction of the mth magnetic dot region from the innermost circumference and a number Nm of dot rows in the down track direction of the mth region meet a relationship represented by L0{Nm?3/2?0.3}?Wm?L0{Nm?3/2+0.

Abstract: A magnetic tape drive having a tape drive system for moving magnetic tape, tape read/write and servo system, tape cartridge load/unload systems, I/O communications, memory; and a control system, operates in three modes to conserve energy consumption. A first low power mode powers the I/O communications, the memory, and the control system. If a magnetic tape cartridge is in loaded position in the magnetic tape drive, the second low power mode powers the same as the first low power mode, and additionally powers the tape drive system to apply tension to a magnetic tape of the magnetic tape cartridge. In the first and the second low power modes, the control system operates the I/O communications, the memory and the control system to respond to and execute commands received at the I/O communications if the commands are executable without magnetic tape access. The third, full power mode, is entered if a command received at the I/O communications requires magnetic tape access.

Abstract: A hard-disk drive. The hard-disk drive includes a magnetic-recording disk in which tracks adjacent to each other are magnetically separated, a spindle motor which drives the magnetic-recording disk, a magnetic-recording head equipped with write element and read element, an actuator for positioning the magnetic-recording head on a predetermined track on the magnetic-recording disk, and a control unit. The control unit is configured to store information about an over-write-only track that is provided for a plurality of tracks including n consecutive tracks in at least a partial radial area of the magnetic-recording disk and an offset amount. In a radial area of the magnetic disk where the over-write-only track is located, the control unit is configured to record with an offset by an offset amount from a center of a track toward the over-write-only track with respect to n?1 tracks of the plurality of n tracks, excluding the over-write-only track.

Abstract: This application discloses a hard disk drive using a self-resonant frequency band of a Voice Coil Motor far above its operational frequency band to predict Rapid Off Track events before its head stack assembly can deliver the disruption to the slider writing a track. A circuit board and/or an integrated circuit are disclosed in various embodiments to predict the ROT events using the self-resonant frequency band and/or to respond to the prediction to suppress the slider writing.

Abstract: A disk for a hard disk drive. The disk includes a first magnetic layer supported by a substrate and an intermediate layer adjacent to the first magnetic layer. The disk also includes a second magnetic layer that is adjacent to the intermediate layer and includes barium. The barium second magnetic layer has a mechanical hardness so that a protective layer such as COC is not required for the disk.

Abstract: A device for detecting defect signals on an optical disc includes a finite state machine (FSM) to control a servo system of an optical disk drive. When the FSM is in a DETECT state and defect signals are greater than thresholds, a detection counter is set to a first predetermined value and the FSM enters an ARM state. In the ARM state, when the detection counter counts zero, the FSM enters a KICK state and the detection counter is set to a second predetermined value. In the KICK state, a flag signal XDFCT is asserted. When the detection counter in the KICK state counts to zero, the FSM enters a WAIT state and the detection counter is set to a third predetermined value. When the flag signal XDFCT is asserted, corresponding servo control signals for the servo system are clamped to a programmable constant voltage.

Abstract: In a voice coil motor (VCM) of a disk drive, a coined feature formed on a ferromagnetic plate reduces magnetic flux leakage from a disk drive without increasing the weight of the drive or adding complexity to the manufacturing process. The coined feature is shaped and positioned to alter the path of magnetic flux lines produced by the VCM in a way that significantly reduces the flux leakage from the VCM. The coined feature may be formed without adding material to the ferromagnetic plate by the same stamping process used to fabricate the plate.

Abstract: A low hysteresis pivot bearing suitable for a variety of applications. The relationship between torque and angular displacement is substantially linear, with negligible residual hysteresis. The pivot bearing includes a pivot shaft and an inner sleeve pivotally attached to the pivot shaft by an inner bearing. An outer sleeve is pivotally attached to the inner sleeve by an outer bearing. An inner sleeve actuator continuously rotates the inner sleeve relative to the stationary shaft.

Abstract: A plurality of wiring traces are formed on a base insulating layer, and a metal layer is formed on the opposite surface of the base insulating layer. Two adjacent wiring traces constitute a transmission line pair. The width of the wiring trace is set to not more than 250 ?m, and the distance between the adjacent wiring traces is set to not less than 8 ?m. The thickness of the base insulating layer is selected to cause differential impedance of the transmission line pair to be not less than 10? and not more than 50?.

Abstract: A hard disk drive includes a head stack assembly including a read/write head mounted thereon and an actuator arm pivoting over a disk around a pivot shaft installed on a base, a pivot shaft holder rotatably supporting the pivot shaft and to which the actuator arm is coupled, and a bobbin provided at the opposite side of the actuator arm with respect to the pivot shaft holder and having a voice coil motor coil installed on at least one surface thereof, a crash stop coupled to the base and restricting displacement of the actuator arm, and a contact area reduction portion provided on at least one of the bobbin and the crash stop and including at least one non-contact section, in which the bobbin and the crash stop do not contact each other, in a contact section of the bobbin and the crash stop, when the bobbin and crash stop contact each other, to reduce the contact area between the bobbin and the crash stop.

Abstract: According to one embodiment, an assembly includes a first member configured to have a first linear expansion coefficient, a second member configured to have a second linear expansion coefficient smaller than the first linear expansion coefficient, a pair of connecting members configured to connect the first member with the second member, and a notch configured to be formed in the second member between the connecting members and configured to reduce a sectional area of the second member on a section perpendicular to a straight line that connects the connecting members.

Abstract: The present invention provides a VCM driver realizing low power consumption and high accuracy and a PWM amplifier compensating a dead time distortion. A phase compensator, a ?? modulator receiving an output signal of the phase compensator and converting the output signal to a control code of predetermined bits, a PWM modulator receiving the control code to produce a PWM signal, and an output circuit receiving the PWM signal to drive a voice coil constitute a forward path. A sense amplifier sensing a current of the voice coil, an ADC receiving an output signal of the sense amplifier, a low-pass filter receiving an output signal of the ADC, and a decimation filter receiving an output signal of the low-pass filter constitute a feedback path. An output signal of the decimation filter is fed back to the input side of the phase compensator to form a major feedback loop having a first-order characteristic loop gain.

Abstract: According to one embodiment, an actuator stopper contacts a butting portion of an actuator which moves a head in a movement direction in a movement plane, and restricts a movement range of the actuator along the movement direction. The actuator stopper includes a first portion and a second portion. The first portion is configured to be positioned at an upstream side along the movement direction and contact the butting portion of the actuator. The second portion is configured to be positioned at a downstream side along the movement direction, have a smaller height than the first portion along a direction vertical to the movement plane, and be formed integrally with the first portion.

Abstract: A system and method for reducing resonance in a data transfer system are herein disclosed. A data transfer system comprises a bearing and a guide member. The bearing further comprises an outer ring. The guide member is arranged relative to the bearing so as to guide the outer ring for movement relative to the guide member, and to induce an axial preload in the bearing assembly.

Abstract: Method and apparatus for attenuating resonances in a flex circuit which interconnects a stationary element and a moveable element, such as a connector and a head stack assembly (HSA) in a data storage device. An intermediary portion of the flex circuit forms a dynamic loop between the stationary element and the moveable element. A damper member is attached to the flex circuit so as to continuously extend adjacent the stationary element and along less than an overall extent of the dynamic loop. The damper member attenuates resonances excited in the flex circuit during movement of the moveable element.

Abstract: A system for implementing current shaping for retract of a voice coil motor (VCM) includes drive circuitry coupled to drive the VCM according to a logic state of the system. Current shaping circuitry is configured to temporarily decrease the bandwidth of a VCM transconductance loop in response to a control signal. The transconductance loop includes at least the VCM, the current shaping circuitry and the drive circuitry. The system also includes logic configured to provide the control signal at an end portion a drive logic state to enter a current shaping logic state as a transition from the drive logic state to a floating logic state to reduce current through the VCM such that acoustic emissions from the VCM are mitigated during the retract.

Abstract: A relative movement is induced between a head and first and second recording tracks along the boundary between the first recording track and the second recording track. The first recording track includes first magnetic dots arranged in the down-track direction at constant intervals. The second recording track includes second magnetic dots arranged in the down-track direction at constant intervals identical to the intervals of the first magnetic dots. The second magnetic dots are dislocated in the down-track direction relative to the first magnetic dots. The positional information is generated to specify the position of the head based on the difference between a first output of signals read from the first magnetic dots and a second output of signals read from the second magnetic dots.

Abstract: An integrated pivot-carriage for a hard-disk drive. The integrated pivot-carriage includes a carriage having a center-bore with an integrated bearing-spacer portion. The integrated pivot-carriage also includes a pivot-shaft configured to provide support for rotation of the carriage. The pivot-shaft is disposed within the center-bore of the carriage. In addition, the integrated pivot-carriage includes at least one raceless ball-bearing that is configured to allow rotation of the carriage about the pivot-shaft. The raceless ball-bearing is disposed between the pivot-shaft and the carriage.

Abstract: An apparatus and method are disclosed for writing data accumulated in a buffer on a tape medium in such a way that overwriting is prevented. The apparatus comprises a write unit configured for writing first data in a first position extending over a first track and an area adjacent to the first track, writing second data in a second position extending over a second track and an area adjacent to the second track, and writing the first data and the second data in a third position extending over a third track and an area adjacent to the third track. Furthermore, the apparatus comprises a processing unit configured for preventing the first data written in the first position from being overwritten with the second data written in the second position or with the first data written in the third position.

Abstract: A tolerance ring configured to improve mass eccentricity of an actuator arm assembly. The tolerance ring has a cylinder with a predetermined length between two ends, with a gap along the predetermined length of the cylinder, the gap having a first and a second edge, the cylinder having an aperture in the surface of the cylinder at the second edge.

Abstract: A carriage arm assembly includes: a carriage arm that holds a head slider and a head IC communicating with the head slider and has a first engagement part between the head slider and the head IC; a signal relay member that are provided on the carriage arm and relays signals between the head slider and the head IC; and a presser member that has a second engagement part engaged with the first engagement part and is attached to the carriage arm by engaging the first and second engagement parts with each other, the signal relay member being held by a projection provided in one of the carriage arm and the presser member and a recess that is provided in the other and is engaged with the projection.

Abstract: A carriage block body is coupled to a support shaft for relative rotation. The carriage block body defines a bearing hole receiving the support shaft. A carriage arm extends from the carriage block body along an imaginary plane perpendicular to the longitudinal axis of the support shaft. The carriage arm has a wall surface defining a cylindrical space at the tip end of the carriage arm. A projection is formed on the wall surface at a position off an intermediate plane set perpendicular to the longitudinal axis of the cylindrical space so that the cylindrical space is equally divided into a first cylindrical space and a second cylindrical space by the intermediate plane. The projection protrudes into the first cylindrical space.

Abstract: A manufacturing method of a magnetic recording medium, the magnetic recording medium having a structure where plural magnetic recording areas and isolation areas in a magnetic recording layer are formed on a non-magnetic substrate, the isolation areas being configured to magnetically isolate the magnetic recording areas, the manufacturing method includes a step of forming the magnetic layer on the non-magnetic substrate, the magnetic layer being made of a hard magnetic material having a magnetic coercive force whereby magnetic recording is impossible; and a step of performing ion implantation partially at positions corresponding to the plural magnetic recording areas of the magnetic layer so that the magnetic recording areas are formed by reducing the magnetic coercive force in the positions of the ion implantation to a magnetic-recordable magnetic coercive force, and allowing the isolation areas to maintain the magnetic coercive force whereby magnetic recording is impossible.

Abstract: A storage apparatus includes a magnetic circuit applying driving force to a carriage. The magnetic circuit includes a first yoke provided with a magnet. An end of the first yoke is secured using a first fastening member screwed in a threaded hole in an end of the base. A second yoke is opposed to the first yoke, and an end of the second yoke is secured using a second fastening member screwed in a threaded hole in another end of the base. A driving coil is held by the carriage and disposed between the first yoke and the second yoke so that the first yoke and the second yoke are attracted to each other by magnetic force of the magnet.

Abstract: A hard disk drive (HDD) includes a base including a voice coil motor (VCM) which drives an actuator, a cover combined with an upper surface of the base, and a magnetic leakage flux reducer adjacent to the VCM to reduce a magnetic leakage flux leaked from the VCM. Therefore, the HDD includes a simple structure to be made light and reduces the magnetic leakage flux which affects the VCM.

Abstract: A method and apparatus for electrically coupling a slider to a controller circuit are disclosed. In one embodiment, a pre-amplifier with an integrated electrical connector (I-connector) may be connected via an electrical trace to a slider and via a head stack assembly flexible circuit to a control circuit. The pre-amplifier may have two parallel series of spring probe claws, two parallel series of contact pegs, two slots, or a slot and a rotary cam.