Abstract: A method for forming servo patterns on a magnetic-recording disk. The method includes moving a magnetic-recording head in an opposite direction to a pattern development direction, when there is a faulty servo pattern. The method also includes positioning a write element of the magnetic recording head on a track of the faulty servo pattern and forming a reserve servo pattern at a different circumferential location from that of the faulty servo pattern. The method includes moving the magnetic-recording head in the pattern development direction. The method further includes positioning the read element on the track of the faulty servo pattern and forming a new servo pattern in the pattern development direction at the circumferential location of the faulty servo pattern on a track disposed between the track of the faulty servo pattern and an outside diameter of the magnetic-recording disk, based on data read from the reserve servo pattern.

Abstract: A magnetic-recording-disk test-head. The magnetic-recording-disk test-head includes a slider, a test pad and a slider-surface-shape control mechanism. The slider includes a leading edge and a trailing edge. The test pad is disposed at a trailing-edge side of the slider and is configured to remove and to detect asperities on a magnetic-recording disk. The slider-surface-shape control mechanism is configured to change a shape of an air-bearing surface of the slider and is disposed at a leading-edge side of the slider.

Abstract: A method for positioning a magnetic-recording head. The method includes correcting amplitude of each burst signal of a plurality of burst signals read out with the magnetic-recording head from each respective burst pattern of a plurality of burst patterns. In addition, the method includes computing a deviation of the magnetic-recording head from a track based on corrected amplitudes of the plurality of burst signals. Moreover, the method includes positioning the magnetic-recording bead on the track based on the deviation of the magnetic-recording head.

Abstract: A disk drive. The disk drive includes a disk and a head-slider. The head-slider includes an air-bearing surface. The air-bearing surface includes a trailing-edge rail surface, an inner trailing-edge pad, and an outer trailing-edge pad. The pad surface of the outer trailing-edge pad includes a straight outer edge slanting outward; and, the angle of the outer edge with respect to the longitudinal direction of the head-slider is ?1. The pad surface of the inner trailing-edge pad includes a straight inner edge slanting inward; and, the angle of the inner edge with respect to the longitudinal direction of the head-slider is ?2. For absolute values of skew angles at an outermost data track position and an innermost data track position on the disk that are denoted by ?1 and ?2, respectively, the following conditions are satisfied: ?2??1, ?1+?1?90°, and ?1?2, ?2+?2?90°.

Abstract: A hard-disk drive. The hard-disk drive includes a magnetic-recording disk including tracks on which a plurality of patterned bit-cells that are isolated magnetically are aligned at predetermined alignment pitches. The hard-disk drive includes a magnetic-recording head which is configured to follow tracks, and to write and to read data. The hard-disk drive includes a signal-processing unit which is configured to generate a recording signal based on a write-clock signal with cycles corresponding to alignment pitches of patterned bit-cells, and to output a recording signal. The hard-disk drive includes a phase-detecting unit which is configured to detect a phase of the write-clock signal when the magnetic-recording head reaches an end point of a predetermined range. The hard disk drive includes a determination-processing unit which is configured to determine success of data writing based on a difference between an expected value and a detected value of the phase of the write-clock signal.

Abstract: A magnetic recording medium having a magnetic pattern magnetically partitioning a magnetic layer, formed on a non-magnetic substrate, wherein the magnetic pattern is comprised of magnetic regions and non-magnetic regions surrounding each of the magnetic regions, the non-magnetic regions form depressions, the magnetic pattern comprises data areas and servo information areas, and the difference between the areal ratio of the depressions in the data areas and the areal ratio thereof in the servo information areas is within ±10%. The magnetic areas preferably comprise a magnetic layer having a granular structure comprised of magnetic grains each surrounded by an oxide, or a two-layer structure comprising the granular structure and a non-granular structure formed on the granular structure. The magnetic recording medium exhibits stable head-floating characteristics, and thus, the largest floating height can be reduced, and a high recording density can be obtained.

Abstract: Various embodiments of the present invention provide systems and methods for determining changes in fly-height. For example, various embodiments of the present invention provide storage devices that include a storage medium having servo data thereon. A read/write head assembly is disposed in relation to the storage medium. A servo based fly-height adjustment circuit receives the servo data via the read/write head assembly, and calculates a first harmonics ratio based on the received data and compares the first harmonics ratio with a second harmonics ratio to determine an error in the distance between the read/write head assembly and the storage medium.

Abstract: A device comprising at least one sensor configured to sense disturbances applied to the data storage device and to generate signals based on the sensed disturbances, and a controller configured to receive the signals from the at least one sensor and to detect jerk events in the sensed disturbances based at least in part on vector differentials of the received signals.

Abstract: A moveable ramp arrangement having a traditional front side while the back side has an extended rotational park position used to support the read/write heads while the ramp is in the open position before and during disc installation.

Abstract: A hard disk drive with multiple heads coupled to multiple disks. The disk drive switches between heads when writing or reading data to access different disk surfaces. As described above, there is a head skew time associated with switching heads. The disk drive includes a circuit that switches heads in accordance with a sequence that is a function of a head skew value. For example, the sequence may include switching from a first head to a third head and from a third head to a second head.

Abstract: A magnetic recording medium of the present invention includes, on a substrate (1), at least a magnetic layer (2) and a carbon protective layer (9) that covers the magnetic layer (2), wherein a convex part (7) serving as a magnetic recording area, and a concave part (6) serving as a boundary area that separates the magnetic recording area are provided on the surface of the magnetic layer (2), and a barrier layer (8) containing mainly Cr or Ti is formed between the concave part (6) serving as the boundary area and the carbon protective layer (9).

Abstract: A disk drive is disclosed comprising a disk comprising a plurality of tracks, and a head actuated over the disk. A plurality of refresh zones are defined, wherein each refresh zone corresponds to a plurality of the tracks. Data is written to a first refresh zone, and a first zone counter is updated for a second refresh zone at a first rate. Data is written to a third refresh zone, and the first zone counter is updated for the second refresh zone at a second rate different than the first rate.

Abstract: Recording heads for data storage systems are provided. Recording heads illustratively include a write pole, a bumper, a dielectric layer, and a surface. In some embodiments, a portion of the surface includes portions of the write pole, bumper, and dielectric layer. The write pole, bumper, and dielectric layer are illustratively made from materials that have polishing rates. In some embodiments, the polishing rate for the write pole material is more similar to the polishing rate for the bumper material than it is to the polishing rate for the dielectric layer material.

Abstract: According to one embodiment, a recording medium driving device includes: a recording medium including a plurality of groove regions and land regions, wherein each of the groove regions is formed in a groove formed on top surface of the recording medium and having an arrangement of a magnetic domain formed for each bit, and each of the land regions forms a flat surface on the top surface of the recording medium and in between a pair of the groove regions in adjacency; a head slider disposed to face the top surface of the recording medium; a head element mounted on the head slider; a heater mounted on the head slider and configured to cause a projection in the head element by heat; and a control circuit configured to cause the projection to contact with the land region at time of performing zero calibration for the projection.

Abstract: A method is presented for setting a wrap angle of a read/write head having a servo element and multiple read elements, where the servo element and the read elements can detect a servo signal. The method includes moving a sequential information storage medium having a longitudinal axis and a servo band encoded therein adjacent to the read/write head. The longitudinal axis and a flat upper surface of the read write head define the wrap angle. The method further includes detecting the servo signal using one of the read elements. If the read element is unable to detect the servo signal, then the remaining read elements are sensed to detect the servo signal.

Abstract: A magnetic recording medium comprising a magnetic layer having a magnetic recording pattern comprising elevations constituting magnetic recording regions and depressions constituting boundary regions for partitioning the magnetic recording regions, and a continuous protective carbon overcoat on the magnetic layer, characterized in that portions of the carbon overcoat located on the magnetic recording regions-constituting elevations of the magnetic layer are thicker than portions of the carbon overcoat located on the boundary regions-constituting depressions of the magnetic layer. The protective carbon overcoat is formed by a CVD method. The boundary regions-constituting depressions are preferably subjected to exposure to plasma, and have modified magnetic characteristics. The magnetic recording regions exhibit high corrosion resistance and the magnetic recording medium has enhanced environmental resistance.

Abstract: A contact type thin film magnetic head and method of using the same are provided. The contact type thin film magnetic head comprises a head element that is provided on a disk-facing surface of a slider, a magnetic disk, and heating elements disposed in a plane position different from that of the head element. A protective layer covers the heating elements and the head element. The heating elements and the protecting layer are formed on the disk-facing surface of the slider. The protective layer protrudes further toward the magnetic disk than the head element.

Abstract: Thin film perpendicular magnetic head with a narrow main pole capable of a high recording density in excess of 100 gigabits per square inch and generating a high magnetic recording field, while also being modified to suppress remanent magnetic fields occurring immediately after writing operation. A return path is provided for supplying a magnetic flux to the main pole, and an conductive coil for excitation of the main pole and return path. The main pole has a pole width of 200 nanometers or less, and a magnetic multilayer made up of a high saturation flux density layer and low saturation flux density layer. The low saturation flux density layer and the high saturation flux density suppress remanent magnetization and prevent erasing after writing by utilizing a closed magnetic domain structure in the pole.

Abstract: According to one embodiment, a PMRM includes a substrate, a soft magnetic underlayer above the substrate, an underlayer above the soft magnetic underlayer, an oxide-containing magnetic layer above the underlayer, and a ferromagnetic layer above the magnetic layer having no oxides. The underlayer controls orientation and segregation of the magnetic layer. The oxide-containing magnetic layer comprises at least two or more magnetic layers, a Cr concentration of the magnetic layer adjacent to the ferromagnetic metal layer is between about 23 at. % and about 32 at. %, and a difference between the Cr concentration of the magnetic layer adjacent to the ferromagnetic metal layer and a magnetic layer having a lowest Cr concentration among the at least three magnetic layers is less than about 25 at. %, the magnetic layer with a lowest Cr concentration has a granular structure, and a nucleation field is greater than about 159.2 kA/m.

Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole having a trailing side and two lateral sides, a magnetic shield near the trailing side and both lateral sides of the main magnetic pole, the magnetic shield comprising: a first soft magnetic film with a relatively high saturation flux density positioned facing depthwise from a floating surface side thereof, a second soft magnetic film with a relatively low saturation flux density, and a first non-magnetic film. The head also includes a non-magnetic film interposed between the magnetic shield and the main magnetic pole, a first magnetic film magnetically coupled to the magnetic shield and the main magnetic pole on a side opposite a floating surface side thereof, and a coil surrounding a magnetic circuit, the magnetic circuit comprising the main magnetic pole and the first magnetic film. Other systems and methods are also described.

Abstract: Embodiments of methods and systems for controlling access to information stored on memory or data storage devices are disclosed. In various embodiments, fluid-mediated modification of information or access to information is utilized. According to various embodiments, data storage devices designed for rotating access are described which include rotation-activated fluid control mechanisms.

Abstract: A method of controlling a writing or reading operation of a disk drive. The method includes determining whether a writing control signal or a reading control signal, and a flying height control signal to control a flying height of a head are in enabled states, and when the writing control signal or the reading control signal and the flying height control signal are in the enabled states, performing the writing operation or the reading operation.

Abstract: In one embodiment, a method for removing a resist includes irradiating, with an UV light having a wavelength of less than about 240 nm, a structure having a resist on a pattern surface in an atmosphere having oxygen. The resist is used as a mask as it remains above the pattern after the pattern has been transferred to a magnetic recording medium surface having a magnetic film thereon, and the irradiating is performed during production of the magnetic recording medium. In another embodiment, a method for forming a magnetic recording medium includes applying a resist to a surface of a magnetic film above a substrate, curing the resist by irradiating the resist with first UV light to form a pattern, transferring the pattern to the magnetic film using the pattern, and removing the resist by irradiating using second UV light having a shorter wavelength in an atmosphere including oxygen.

Abstract: A disk drive. The disk drive includes a head, an actuator, and a controller. The head accesses a disk. The actuator is configured to support the head and to move the head by action of a voice-coil motor in a substantially radial direction of the disk. The controller is also configured to perform servo control of the actuator by using servo data read out by the head. The controller includes at least one of a plurality of notch filters having a fixed center frequency inserted in a servo-control loop. The controller is configured to increase an attenuation rate by at least one of the plurality of notch filters having the fixed center frequency at a designated frequency, when a target position of the head is at a position selected from the group consisting of a position outside of a specified region and a position within the specified region.

Abstract: In a positioning control system for a head of a magnetic disk device etc, a frequency of a disturbance oscillation having a specific oscillation component whose amplitude changes with a head position, is selected as a target frequency. Next, a resonance filter is so designed that it has a resonance characteristic at the target frequency and a variable gain device A having the gain changing with head position and a variable gain device B having inverse characteristics to the device A are connected to input and output terminals of the resonance filter, respectively. Input to the filter is made 0 during seek operation and an error signal is used as the input to the filter through the device A after the end of the seek operation. The variable gain devices A and B are controlled so that their product becomes 1.

Abstract: An encoder is capable of being used to compensate for the tilting of a movable object in an apparatus. The encoder includes a fixed scale, and a movable scale integrated with an object that moves during an operation of the apparatus and having a plurality of patterns that are out of phase from each other with respect to the direction of movement of the object. The encoder may be employed by a hard disk drive (HDD) and a servo track recording apparatus. The movable scale is integrated with an actuator arm of the HDD for positioning a read/write head of the HDD, and the fixed scale is fixed to the housing of the HDD. The servo track recording apparatus can use the encoder to record servo track information precisely on a disk.

Abstract: This application discloses a hard disk drive and operates it based upon using a first and third harmonic amplitude generated from reading a repeated pattern of bits written to a track on a disk surface. Both amplitudes are used to create a first data set and the third harmonic amplitude is used as a single tone to create a second data set. A conversion factor between these two is determine, which may be used to convert the first data set under other conditions into a temperature insensitive table of the electrical stimulus of a vertical micro-actuator and the flying height change of the slider. The hard disk drive may be calibrated during manufacture and/or in the field.

Abstract: A patterned-media magnetic recording disk drive has compensation for write head track misregistration (TMR) from the track centerline. As the disk rotates, the read head detects angularly spaced servo sectors and generates a position error signal (PES) which is used by the servo control system to maintain the read head on track. As the disk rotates, the read head also detects angularly spaced synchronization marks, which are used to control the write clock so that magnetization reversal of the magnetic write field from the write head is synchronized with the position of the data islands. If there is TMR of the write head, there will be an effective shift of A(p in the timing of when the center of the data islands pass through the write field. The disk drive includes write clock phase adjustment circuitry that correlates the PES with ?? to compensate for TMR of the write head.

Abstract: An actuator assembly (22) for positioning a head (16) of a tape drive (10) relative to a storage tape that moves along a tape path (24) includes a first actuator (228), a second actuator (230) and a controller (26). The actuators (228, 230) move the head (16) in a direction that is substantially perpendicular to the tape path. The first actuator (228) is mounted to the second actuator (230) at a location that is based on a position of a resonance node (680) of the second actuator (230). The controller (26) controls linear positioning of the first actuator (228) and the second actuator (230) relative to the storage tape on a closed-loop basis. The actuators (228, 230) can each include voice coils (246, 260). The second actuator (230) can include two positioner guides (253A, 253B) that are configured in a substantially collinear configuration or in a triangular configuration with the head (16).

Abstract: Methods and devices are provided for microwave-assisted magnetic recording with collocated microwave and write fields. An illustrative device includes a magnetic write pole and one or more alternating-field components. The magnetic write pole is configured for providing a magnetic write field. The one or more alternating-field components are disposed to at least partially coincide with the magnetic write pole. The one or more alternating-field components are configured to provide an alternating magnetic field having a microwave frequency and an orientation that is at least partially transverse to the magnetic write field.

Abstract: According to one embodiment, a perpendicular magnetic recording medium includes at least one soft magnetic underlayer above a substrate, a seed layer above the at least one soft magnetic underlayer, an intermediate layer above the seed layer, a magnetic recording layer above the intermediate layer, and an overcoat layer above the magnetic recording layer, wherein the seed layer includes a second seed layer above a first seed layer. In another embodiment, the seed layer is a multilayered structure of at least two cycles of a unit of layered film which includes a first seed layer and a second seed layer. The first seed layer includes a non-magnetic alloy having a Face-Centered-Cubic (FCC) structure, and the second seed layer includes a soft magnetic alloy having a FCC structure. Other structures are also disclosed, according to more embodiments.

Abstract: There is provided a method of manufacturing a magnetic recording medium where a magnetic layer is formed on a substrate, followed by formation of a magnetic pattern, which is a method producing few defective products with low production cost, the method of manufacturing a magnetic recording medium having magnetic recording patterns which are magnetically separated, including, in the following order: a step of forming a magnetic layer on a substrate which has an opening in the centre; a step of applying a resin film to the magnetic layer; a step of pressing against the substrate a film-type mold on which an uneven pattern has been formed; a step of transferring the uneven pattern of the mold onto the resin film; a step of separating the mold from the substrate; and a step of forming magnetic recording patterns on the magnetic layer using the uneven pattern which has been transferred.

Abstract: A data storage circuit includes a hard disk drive (HDD) and a fall sensor. The HDD includes a rotatable media platter operable to receive and store data; a read/write head operable to communicate with the media platter by writing data to the media platter and by reading the data from the media platter; an arm supporting the read/write head; a motor coupled to the arm and operable to move the arm to and from the media platter; a drive controller operable to control the media platter, the read/write head and the servo motor; a general purpose input/output (GPIO) terminal coupled to the drive controller; and a data interface terminal coupled to the drive controller. The fall sensor is communicatively coupled to the drive controller and is configured to send an interrupt trigger signal to the drive controller when the drive is falling.

Abstract: A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern, comprising a step of forming a magnetic layer contains 0.5-6 atomic % of an oxide on a non-magnetic substrate; and a step of exposing regions of the magnetic layer, which magnetically partition the magnetic recording pattern, to a reactive plasma or reactive ion. The magnetic layer preferably has a non-granular structure, and in-plane orientated. After the step of exposure of the magnetic layer to a reactive plasma or reactive ion, a surface at least in said regions of magnetic layer having been exposed to the reactive plasma or reactive ion is preferably irradiated with an inert gas. Thus, a magnetic recording medium having a magnetic recording pattern with a high precision, and having high electromagnetic conversion characteristics and high recording density can be produced with an enhanced productivity.

Abstract: The flying heights of magnetic heads of a disk drive are set using an FOD (flying on demand) method in a bank mode. A first signal for adjusting the flying height of a magnetic head is issued to each magnetic head and the value of the first signal is scaled by scale values set for the magnetic heads, respectively, with one of the scale values differing from the others. The value of the first signal is changed until the magnetic head associated with the scale value different from the others touches down. A flying height for the magnetic head which touched down is determined based on the value of the first signal at the time of touch-down. The process is repeated, however with a different bank of scale values each time and set in such a way as to cause the sequential touch-down of the remaining magnetic heads, and determinations of flying heights for the magnetic heads.

Abstract: Embodiments of methods and systems for controlling access to information stored on memory or data storage devices are disclosed. In various embodiments, fluid-mediated modification of information or access to information is utilized. According to various embodiments, data storage devices designed for rotating access are described which include rotation-activated fluid control mechanisms.

Abstract: A hard-disk drive (HDD) with a current adjustment component is provided. The current adjustment component changes an amount of current to a magnetic-recording head of the HDD to cause a change in the strength of a magnetic write field produced by the magnetic-recording head in response to a determination that a present position of the magnetic-head head is not in a desired position. To illustrate, in response to a determination that the present position of the magnetic-recording head is further away from an edge of a current track being written than a desired position of the magnetic-recording head, the current adjustment component increases the current to the magnetic-recording head to cause an increase in the strength of the magnetic write field. The change in the strength of the magnetic write field causes data, written by the magnetic-recording head, to be located at a desired location on the magnetic-recording disk.

Abstract: A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern on at least one surface of a nonmagnetic substrate, characterized by comprising a step of reacting portions of a magnetic layer, formed on the non-magnetic substrate, with ozone to modify magnetic properties of said portions of the magnetic layer for forming the magnetically partitioned magnetic recording pattern. The magnetic layer can be a two-layer structure comprising a magnetic layer having a granular structure and formed thereon a magnetic layer having a non-granular structure. The produced magnetic recording medium exhibits a greatly enhanced recording density while recording/reproducing characteristics equal to or better than those of the heretofore proposed magnetic recording mediums are maintained, and it can be produced with an enhanced efficiency.

Abstract: A read/write head is moved across a contact-start-stop (CSS) zone on a data storage disk during the spin-up and/or spin-down of the disk. Moving the head during spin-up and/or spin-down may reduce the concentration of wear along a surface of the CSS zone.

Abstract: A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern on a surface of a nonmagnetic substrate, which comprises the following steps. Step (A) of forming a magnetic layer on a non-magnetic substrate, step (B) of forming a carbon layer on the magnetic layer, step (C) of forming a resist layer on the carbon layer, step (D) of forming a negative pattern of magnetic recording pattern on the resist layer, step (E) of removing the portions of resist layer and carbon layer in regions corresponding to the negative pattern, step (F) of removing at least a surface layer portion of the magnetic layer in the regions corresponding to the negative pattern, and optional step (G) of removing the residual resist layer and carbon layer. The produced magnetic recording medium has a recording/reproducing property equal to or better than conventional ones and exhibits a high recording density.

Abstract: Harmonic selection for track following is described for a hard disk drive comprising at least one magnetic disk capable of storing data and spinning, a controller capable of controlling a read/write head capable of reading and writing data while following a track on a surface of the at least one magnetic disk, and a memory device capable of storing data relating to the operation of the hard disk drive. A drive function test on the hard disk drive is performed, during which harmonic frequencies are identified which cause disturbances for the hard disk drive. Data regarding the harmonic frequencies which cause the greatest disturbances for the hard disk drive is stored in the memory device. The data regarding the harmonic frequencies which cause the greatest disturbances is forwarded to the controller upon the at least one magnetic disk spinning.

Abstract: A method of writing a servo pattern in a hard disk drive includes manufacturing a master pattern, and writing the reference servo pattern to the disk by using the master pattern and a magnet for magnetizing the disk. The master pattern includes a plurality of ammonite cycles that have substantially the same pattern as the reference servo pattern and are radially formed from the outside toward the inside of the disk. A final servo pattern may be written using the reference servo pattern.

Abstract: A portable apparatus having an electronic control system and a control method thereof are provided. The portable apparatus comprises an operation system, an accessing device and a basic input/output system (BIOS), and the electronic control system comprises a G-sensor and an embedded controller (EC) for initializing the G-sensor, wherein the G-sensor senses the acceleration of the portable apparatus and compares the acceleration value with the threshold value. The operation system comprises an application program (AP) and an advanced configuration and power interface (ACPI). When the acceleration value is higher than the threshold value, the G-sensor sends out a first signal to the EC, and the EC sends out a second signal to the BIOS, and the BIOS sends out a third signal to the ACPI, and the ACPI sends out a fourth signal to the AP to give a park command for parking the reading head of the accessing apparatus.

Abstract: According to one embodiment, there is provided a head flying height control method for controlling a flying height of a magnetic head from a magnetic storage medium. The magnetic head includes an element portion and a heater that effects a change in a protrusion amount of the element portion due to thermal expansion accompanying heat generation. The head flying height control method includes: causing the element portion to protrude a maximum protrusion amount by increasing a heater power of the heater; first-reducing the heater power based on a relation between the protrusion amount and the heater power until the protrusion amount becomes a predetermined protrusion amount; and second-reducing, if a head-medium property is better than a target value after the first-reducing, the heater power based on a relation between the head-medium property and the heater power so that the head-medium property matches the target value.

Abstract: A method of controlling a filter coefficient of a continuous time filter of a data storage device is provided. The method of controlling filter coefficient includes positioning a magnetic head at a first reference height from surface of a magnetic disk and outputting a plurality of CSM values by measuring a channel state from a read signal output from the magnetic head when changing a cut-off frequency of the continuous time filter, positioning the magnetic head at a second reference height spaced from the first reference height and measuring a bit error ratio from a read signal output from the magnetic head positioned at the second reference height according to at least one CSM value selected among a plurality of CSM values, and controlling a filter coefficient value to determine a cut-off frequency of the continuous time filter according to a measured bit error ratio.

Abstract: According to one embodiment, a storage device has a head configured to read or write data with respect to a storage medium above the storage medium; a head suspension configured to support the head; a lift tab extending from an end on a head side of the head suspension; and a ramp mechanism configured to hold the lift tab at a retracted position spaced apart from the recording medium. The ramp mechanism has: a rotating shaft; and a disk rotatably supported by the rotating shaft and configured to rotate in a retracting direction by coming into contact with the lift tab that is retracting with the head from above the recording medium, and to guide and retract the lift tab to the retracted position.

Abstract: A magnetic recording and reading device includes a perpendicular magnetic recording medium, a perpendicular magnetic head having a recording head width having a heat-generating portion and a reading head, a fine adjustment portion, and a R/W-IC. The perpendicular magnetic head is configured to perform magnetic recording on the recording medium while locally heating the recording medium so as to enable a change of the coercive force of the recording medium during the recording after correcting of the position of the perpendicular magnetic head by the fine adjustment portion is completed, and to perform reading of the magnetic recording information with the aid of the reading head after correcting of the position of the perpendicular magnetic head by the fine adjustment portion is completed.

Abstract: A hard disk drive and its circuit board and an integrated circuit are disclosed using two piezoelectric devices each having one terminal used to generate signal. The first signal goes to one input of a differential amplifier. The second signal goes to an amplifier whose gain is controlled to create an amplified second signal for the differential amplifier whose output and the first and second signals create a selected signal received by an A/D converter to create a sampled signal used to create a linear disturbance signal and/or a rotational compensation signal, which in turn are used to control the gain of the amplifier to minimize a PES envelope and/or a harmonic PES envelope either in calibration or normal operation of the hard disk drive.

Abstract: In a class of embodiments, a method and apparatus for detecting freefall of a disk device (thereby predicting that the disk device will likely suffer imminent physical impact) and typically also preventing damage that a disk drive of the device would otherwise suffer if and when a predicted impact occurs. In some embodiments, a disk device includes a freefall detection processor and a CPU. The freefall detection processor is configured to monitor acceleration data to determine whether the disk device is in freefall and to perform at least one other operation (e.g., decoding of MP3-encoded audio data to generate decoded audio data) while the CPU performs at least one other task. Other embodiments pertain to a portable device including a digital audio processing subsystem and an accelerometer.

Abstract: A method of controlling an HDD includes acquiring a reference FOD voltage profile offering a correlation between flying heights FH of a magnetic head and FOD voltages that if applied to the magnetic head would cause the head to fly at the flying heights (FH) in an idealized situation, determining changes in the FH of the magnetic head during the rotation of the disk by analyzing magnetic signal output from the magnetic head at that time, producing an applied FOD voltage profile based on the changes in the FH of the magnetic head and the reference FOD voltage profile, and applying and FOD voltage to the magnetic head when a write command or a read command is issued in the HDD and at that time regulating the FOD voltage applied to the magnetic head based on the applied FOD voltage profile to maintain the FH of the magnetic head constant as the head tracks along the disk