Abstract: A disk drive includes a rotatable data storage disk, a transducer, an actuator, and a controller. The disk includes information and data tracks that are defined thereon. The transducer is configured to read the information from the disk. The actuator is configured to position the transducer relative to the data tracks. The controller is configured to measure timing between particular information on the disk, to estimate repeatable runout of the disk based on the measured timing, and to compensate for repeatable runout of the disk responsive to the estimated repeatable runout while positioning the transducer relative to a selected track.

Abstract: A data detection circuit includes a transient detector that senses transient events in data. A first data detector path applies a first equalization target to generate a first bit stream from the data. A second data detector path applies a second equalization target to generate a second bit stream from the data. A baseline correction circuit generates a baseline correction signal using the first bit stream when the transient detector does not sense the transient events and the second bit stream when the transient detector senses the transient events. The first equalization target is a non-DC free equalization target and the second equalization target is a DC-free equalization target. When transients are detected during a sector, the detection circuit continues using the DC-free equalization target until the sector ends.

Abstract: Embodiments of the invention provide a manufacturing method for a disk drive which allows highly accurate recording of servo data without substituting the internal gas of the disk drive, and such a magnetic disk drive and servo track writer. In one embodiment, a disk, a magnetic head slider with a head for writing data onto and reading out data from the disk, a suspension for retaining the magnetic head slider, an arm for supporting the suspension, and a driving section for driving the arm are stored into an enclosure. When a servo track write operation is conducted, the enclosure interior is depressurized to an atmospheric pressure lower than normal pressure and then servo data is recorded on the disk.

Abstract: An access performance adjusting method is adapted to a storage apparatus having a storage to prestore a skew quantity that is used to shift a data write starting position of each track of a recording medium depending on a head moving time required to move a head from one track to another track during a sequential access in which a plurality of tracks of the recording medium are accessed sequentially. The method includes measuring an apparatus performance with respect to a combination of the head and the recording medium, calculating a skew adjusting quantity with respect to the combination based on a reference apparatus performance and the measured apparatus performance, and adjusting the skew quantity read from the storage by the skew adjusting quantity and storing the adjusted skew quantity in the storage as an updated value of the skew quantity.

Abstract: A write driver circuit for a magnetic storage medium that communicates with a write head having first and second nodes comprises a first driver circuit having a first input, a first output that communicates with the first node, and a first feedback path between the first input and the first output. A second driver circuit has a second input, a second output that communicates with the second node, and a second feedback path between the second input and the second output. A first write current circuit selectively drives current through the write head in a first direction. A second write current circuit selectively drives current through the write head in a second direction. A first boost circuit decreases a first transition period between current flowing in the first direction and current flowing in the second direction.

Abstract: A storage device configured to load and unload a head against a storage medium, includes a latch mechanism configured to latch the unloaded head, a head moving mechanism configured to move the head, a measuring part configured to measure an unlatch force necessary for unlatching the head latched by the latch mechanism, by applying a constant electrical current to the head mechanism so that the head is moved in a load direction, by measuring a back electromotive voltage, and calculating a moving speed and acceleration of the head, a storing part configured to store information indicating the measured unlatch force in the storage device, and a control part configured to apply a driving electrical current corresponding to the stored information to the head moving mechanism where the head is latched by the latch mechanism at the time of loading.

Abstract: A linear-type tape storage magnetic head device in which track density and the response of a magnetic head is improved is provided. A sliding portion constituting a main sliding surface in contact with a magnetic tape T and a magnetic head element chip portion. A tracking mechanism has a two-stage tracking mechanism of a rough-move tracking mechanism and a fine-move tracking mechanism, with the magnetic head element chip pardon being directly disposed in the fine-move tracking mechanism and the fine-move tracking mechanism being disposed in the rough-move tracking mechanism; the rough-move tracking mechanism makes the magnetic head element chip portion move across the tracks arranged in parallel in the width direction of the magnetic tape T; and the magnetic head element chip portion made lighter in weight provides improved speed-up and accuracy of tracking and high density of the tracks can be obtained.

Abstract: A data storage system in which multiple readback signals are resolved is provided. The data storage system includes a data storage medium configured to store servo marks and data marks. The data storage medium has tracks that are divided into sectors. An array of heads is configured to interact with the data storage medium. A demodulation circuit receives servo signals obtained by at least some heads of the array of heads and computes a resultant servo signal, which is used to adjust a position of the array of heads over the storage medium.

Abstract: A data storage cartridge is equipped with write-once-read-many (WORM) write-protection. The cartridge is compatible with an existing cartridge docking station with a modification to the control logic of the docking station's control module. Specifically, the control logic is altered to recognize that sensing magnets with both sensors requires the docking station to allow data to be written to, but not erased or altered on the cartridge. In this manner, a third possibility of write-protection status is added to the two existing possibilities of full write-protection and no write-protection. Some embodiments of the invention also provide redundant indications of the WORM write-protection status of the cartridge. For example, embodiments of the invention may incorporate a radio-frequency identification (RF) tag within the cartridge and/or a status bit written into a designated WORM register within a media information header during pre-format of the cartridge media.

Abstract: A disk apparatus includes (a) an actuator having a head supporting arm with a tab formed on the arm and a voice coil fixed to the arm, which arm is rotatable on a horizontal rotary shaft as well as on a vertical rotary shaft, (b) a voice coil motor having an upper yoke with a magnet fixed to the upper yoke and a lower yoke sandwiching and confronting the voice coil, and (c) a ramp section guiding and holding the tab at a refuge place. When the actuator at the refuge place starts loading with a starter command, a pulsed driving current is applied to the voice coil temporarily for urging the tab against a tab-holding plane of the ramp section, thereby making use of repulsion force generated on the actuator, so that the tab can leave the refuge place efficiently for carrying out the loading operation.

Abstract: A position control device corrects the displacement of the head by disturbance applied to the disk device by the control system. An adaptive control to an unknown disturbance frequency is performed. The frequency estimation block for estimating the external vibration frequency from a signal that is based on the position error according to the adaptive rule, and a correction table for sequentially correcting the constants of the compensator using this external vibration frequency, are provided. Since the constants of the compensator are sequentially corrected according to the estimated angular frequency, highly accurate follow up control to an external vibration frequency in a wide range becomes possible.

Abstract: A hard disk drive that includes a voice coil motor and a micro-actuator. The disk drive includes a servo with a voice coil motor loop, a micro-actuator loop and an overall loop. The servo is calibrated by first calibrating the voice coil motor loop, then calibrating the micro-actuator loop and finally calibrating the overall loop.

Abstract: The invention relates to a device comprising a disk drive 1 for rotating a disk memory and at least one interface enabling a data flow between a rotating disk memory and at least one other module 10, 12. In order to enable a comfortable use of such a device, it is proposed that the device further comprises means 2 for setting the rotation speed of the disk drive 1 based on an indication of the data rate supported by an interface of the device, which interface is currently to be employed for enabling a data flow between the rotating disk memory and at least one other module 10, 12. The invention relates equally to a method setting the rotation speed of a disk drive 1 according to the capabilities of an interface enabling a data flow between a disk memory rotated by the disk drive 1 and another module 10, 12.

Abstract: A magnetic disk medium of a discrete track recording (DTR) structure and a disk drive using the magnetic disk medium are disclosed. The magnetic disk medium of the DTR structure has positional-error detection servo patterns in a servo region, the positional-error detection servo patterns being formed of null servo patterns. This enables magnetic regions included in the servo region to occupy substantially 50% of the area of the servo region.

Abstract: A magnetic recording medium includes a servo area where servo data used for detecting a position of a magnetic head on a magnetic recording medium is recorded; and a writable data area, arranged side by side with the servo area in a track direction, on which user data is written by the magnetic head. The servo area includes a preamble area where a preamble recording pattern that represents data used for providing a clock synchronization of the servo data is formed by a plurality of magnetic sections; and a burst area where data used for detecting a relative position of the magnetic head with respect to a track center position of the servo data is recorded and on which a single burst recording pattern which is a layout pattern that tilts to the preamble recording pattern with a predetermined tilt angle is formed by a plurality of magnetic sections.

Abstract: An embodiment of a slider in accordance with the present invention for use in a hard disk drive having a rotatable disk can include a plurality of rails arranged across a surface of the slider such that an air bearing is formed when the slider is positioned over the disk and the disk is rotated such that the slider traverse a servo wedge of the disk. The surface of the slider further includes a trailing pad arranged near a trailing edge of the surface of the slider such that when the slider traverses debris having a height higher than minimum height, the air bearing increases such that the slider is not in communicative proximity with the disk for a time at least as long as a time for the slider to traverse the servo wedge.

Abstract: Write control bits are associated with servo pattern data bits to selectively disable or enable a write gate in a HDD write channel for self-servo writing after being sealed but before being vended to a user. The write gate can be disabled and enabled without deenergizing the write channel. A single write delay is calculated from one timing mark to the next to enable writing the next timing mark and portions of the radial pattern and servo pattern between the timing marks.

Abstract: A disk drive includes a rotatable data storage disk, a transducer, an actuator, and a servo burst demodulator. The disk includes a servo burst pattern thereon within a single servo sector. The transducer is configured to generate a read signal from the servo burst pattern. The actuator is configured to position the transducer relative to the disk. The servo burst demodulator is configured to generate a position error signal from the contributions of the servo burst pattern to the read signal, and is configured to generate a fly height signal from the contributions of the servo burst pattern to the read signal. The position error signal is indicative of a radial location of the transducer relative to the disk. The fly height signal is indicative of a height of the transducer from the disk.

Abstract: A disk drive comprising an actuator including a head, a disk, and a processor connected to the actuator by a flex circuit cable. The processor under the control of a program to: apply a control signal for a seek operation and to apply a bias signal to the control signal to approximate the bias imparted by the flex circuit cable. The bias is determined from a data structure that stores: bias values for track zones representative of a first and second bias curves that approximate a bias imparted by the flex circuit cable upon the actuator as the actuator moves the head from the OD to the ID of the disk and from the ID to the OD of the disk, respectively. The bias values representative of the first and second bias curves are determined based upon a non-linear apportionment of track zones.

Abstract: A data storage system includes a magnetic storage medium and a write head configured to be positioned adjacent the storage medium and. The write head includes a magnetic field source configured to apply a magnetic field to the storage medium and an optical near field coupling structure configured to locally heat the magnetic storage medium with an optical near field proximate the magnetic field applied by the magnetic field source. An overcoat layer on the magnetic storage medium enhances absorption of the optical near field.