Abstract: Aspects of the disclosure pertain to a system and method for providing zero gain start (ZGS) and gain acquisition based on an adaptive analog-to-digital converter (ADC) target. The adaptive ADC target is used to collect channel characteristics and based on the adaptive ADC target, an adjusted 2T amplitude target value is generated.

Abstract: According to one embodiment, a disk storage apparatus includes a magnetic head and a controller. The controller determines at regular intervals whether a recording density of a write signal belongs to a low-density region or a high-density region with reference to a reference density. In addition, the controller relatively reduces a current to energize a high-frequency-assisted element at a timing of the low-density region to be less than a current of the high-density region, in accordance with the low-density region or the high-density region in recording the data.

Abstract: Selection of disk drive data tracks for the location of reserved area include providing a media disk with data tracks comprising a user data region. A location is assessed on the media disk with a highest frequency of adjacent track interference and far track interference-refresh potential. The location is then configured to be a reserved area where no user data is written. The reserved area has parameters that are read out first before the disk drive enters an operation enabled state for user interface.

Abstract: Methods and apparatus are provided for detecting a sync mark in a storage system, such as a hard disk drive. A sync mark is detected in a storage system by obtaining one or more branch metrics from a data detector in the storage system; generating one or more sync mark metrics using the one or more branch metrics from the data detector; and identifying the sync mark based on the sync mark metrics. An input data set is optionally compared with a plurality of portions of a sync mark pattern to yield corresponding comparison values and the comparison values can be summed to obtain at least one result. A sync mark found signal is asserted based upon the at least one result.

Abstract: A storage device includes a processor, a vibration detecting sensor that detects a vibration, a plurality of disk drives, and a disk control device that causes the processor to perform an operation of generating a vibration for a disk drive selected from among the plurality of disk drives so that the generated vibration vibrates in a cycle that is shorter than a cycle of the vibration detected by the vibration detecting sensor.

Abstract: Calibrating a frequency filter includes applying a series of input electrical signals at different frequencies to a shock sensor, using circuitry to identify a particular one of the frequencies as a resonance frequency of the shock sensor based on responses of the shock sensor to the series of input signals, and setting a center frequency of the notch filter equal to the particular frequency identified as the resonance frequency of the shock sensor.

Abstract: According to one embodiment, a magnetic disc apparatus includes a magnetic head which reads information stored in a magnetic disc, an arm which supports the magnetic head, and a feedback controller which controls a coarse actuator to move the magnetic head above the magnetic disc by driving the arm, a fine actuator to hold a position of the magnetic head, and a feedback path which feeds back a displacement of the actuator to a target value of the coarse actuator. The feedback controller controls decoupling of a double actuator system which adds up the coarse actuator and the fine actuator.

Abstract: There is disclosed a hard disk drive and an operation method thereof. A method of operating a hard disk drive according to the present invention may include (a) loading drive data required to drive the hard disk drive from a maintenance cylinder area contained in a disk to a memory; and (b) writing test data output from a head into a spare area contained in the maintenance cylinder area, wherein the steps (a) and (b) are carried out within a ready time.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, and a spindle motor operable to rotate the disk. A baseline relationship is generated between a baseline current draw of the spindle motor over a temperature range. An operating current draw of the spindle motor is measured and a corresponding operating temperature is measured. Failure of the spindle motor is predicted based on the operating current draw, the operating temperature, and the baseline relationship.

Abstract: In at least one embodiment, a data storage system is provided. The system includes a controller that is configured to determine a direction of current flow to a first write element to write first data on a magnetic tape and to determine a direction of current flow to each of a plurality of neighboring write elements to write corresponding data on the magnetic tape. The controller is further configured to compare the direction of current flow to the first write element to the direction of current flow to the plurality of neighboring write elements. The controller is further configured to control the first write element to write the first data in response to comparing the direction of current flow to the first write element to the direction of current flow to each of the neighboring write elements.

Abstract: Embodiments of the present disclosure provide for reading data from a physical storage medium, transferring the data between a data channel and a test interface over a parallel data bus, and providing the data from the test interface at a serial port in a serial format.

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of data tracks, wherein each data track comprises a plurality of data sectors. A host write command is received from a host, and previous data is read from at least one data sector which is combined with at least one of the host blocks to generate modified data that is written to the at least one data sector. At least one of a first read command and a first write command is generated, wherein the first read command is for reading the previous data from and the first write command is for writing the modified data to the at least one data sector. At least one of the first read command and the first write command is stored in a command queue for execution based on a rotational position optimization (RPO) algorithm.

Abstract: Systems, methods, devices, circuits for data processing, and more particularly to penalty based multi-variant encoding of data.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, the head comprising a touchdown sensor comprising a resistance. A bias signal is applied at a reference value to the touchdown sensor at a reference temperature, and a corresponding reference resistance of the touchdown sensor is measured. An operating value for the bias signal is generated based on a predetermined operating temperature of the touchdown sensor, the reference resistance, the reference temperature, and a thermal coefficient of resistance (TCR) of the touchdown sensor, wherein the TCR specifies a change in temperature of the touchdown sensor relative to a change in the resistance of the touchdown sensor.

Abstract: Determining a polarity of a piezoelectric (PZT) actuator of a disk drive including a disk for storing data and a head for reading and writing data. A test signal is injected into the PZT actuator and a position signal is received which indicates a position of the head over the disk resulting from the test signal. A test compensation signal is generated based on the received position signal and the polarity of the PZT actuator is determined based on a phase of the generated test compensation signal.

Abstract: A disk drive is disclosed comprising a disk, and a head actuated over the disk, the head comprising a read element radially offset from a write element. A temperature is measured, and an operating write offset is generated based on the measured temperature. Data is written to a target radial location on the disk by radially offsetting the write element based on the operating write offset. An operating read offset is generated based on the target radial location on the disk, and the data is read from the disk by radially offsetting the read element based on the operating read offset.

Abstract: Disclosed are servo pattern writing methods and apparatuses for performing the same. In one example, a method may include providing a plurality of disks having reference servo patterns written thereon; writing align patterns aligned with each other in a horizontal direction of the disk surface, on the plurality of disks, using a reference servo pattern of one of the plurality of disks; and writing a final servo pattern on each disk, using the align pattern written on each disk.

Abstract: Records and filemarks read from data segments are aggregated into at least one single data segment. The records and the filemarks are reorganized and restructured in the single data segment such that buffer utilization is improved.

Abstract: An apparatus, system, and method for automatic unthreading and storage of storage media helps prevent damage to the media, which can otherwise occur when the storage media is left threaded in a storage media drive over an extended period or under adverse conditions. A sensing device may generate a signal or a detector may receive a signal indicating that a predetermined period of time has lapsed or that some other criteria has been met indicating that the storage media should be removed from the storage media drive. An unthread module in the storage media drive receives the signal and automatically unthreads and stores the storage media. A location on the storage media can be marked by the unthread module prior to unthreading such that the media may be returned to the location upon rethreading.

Abstract: A disk drive is disclosed comprising a disk comprising a plurality of tracks, a head attached to a distal end of an actuator arm, and a voice coil motor (VCM) operable to rotate the actuator arm about a pivot bearing including a race and a plurality of ball bearings. The VCM is controlled to execute a first jerk seek in a first radial direction so that the ball bearings slip within the race by a first rotation angle. The VCM is controlled to execute a second jerk seek in the first radial direction so that the ball bearings slip within the race by a second rotation angle, wherein the second rotation angle adds to the first rotation angle in order to rotate the ball bearings relative to the race at a reference angle of the pivot bearing.

Abstract: Aspects of the present invention relate to an apparatus and corresponding method that includes transitioning from a monitor state to a stop write state when a determined position error is greater than a threshold error value for a first predetermined period, and transitioning from the monitor state to a write state when the determined position error is less than the threshold error value for a second predetermined period. Write operations are enabled and signals are provided to operate an actuator to translate a magnetic head laterally in a manner to reduce the determined position error while in the write state. Write operations are disabled and signals are provided to operate the actuator to translate the magnetic head laterally in a manner to reduce the determined position error while in the monitor state. Write operations are disabled while in the stop write state.

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of servo sectors defining a plurality of servo tracks, wherein the servo tracks form a plurality of servo zones, and a servo data rate of servo sectors in a first servo zone is different than a servo data rate of servo sectors in a second servo zone. A disk locked clock is synchronized to the data rate of the servo sectors in the first servo zone, wherein the disk locked clock for generating a timing window relative to the servo sectors. When the head crosses from the first servo zone to the second servo zone, at least one of the disk locked clock and the timing window is adjusted to compensate for a timing transient.

Abstract: Grease wear leveling in a disk drive including an actuator for moving a head over a disk as part of a seek operation. A count of seek operations is maintained and when the count of seek operations exceeds a first threshold number, one or more full stroke seek (FSS) operations are performed until a count of the FSS operations performed reaches a predetermined number. The FSS operation includes moving the head through a substantially wide range of motion. For each of the one or more FSS operations performed, the count of FSS operations performed is adjusted based on whether the most recent FSS operation was performed within a time window. The time window is based at least on a number of interval seek operations performed since a previously performed FSS operation.

Abstract: A shingled magnetic recording hard drive is presented to a resource manager of a host device as an emulated device such as one or more optical media, an array of sequential access media, and/or write-once, read-many device. Data targeted for the emulated device is written to the shingled magnetic recording hard drive.

Abstract: An apparatus and method for providing adaptive disturbance compensation with multi-rate synchronized sampling is disclosed herein. The dynamic disturbance occurring in a media drive during read/write operations is attenuated using the adaptive disturbance compensation scheme. A plurality of compensation filters are used, each of the compensation filters configured to attenuate a disturbance caused by a particular source within the media drive. Each of the compensation filters is computed based on a sampling rate relevant to the respective disturbances.

Abstract: A magnetic-recording head with a first thermal fly-height control (TFC) element and an embedded contact sensor element (ECSE) configurable as a second TFC element. The magnetic-recording head includes a write element, a read element, a first heater element, and an ECSE. The write element is configured for writing data to a magnetic-recording disk. The read element is configured for reading data from the magnetic-recording disk. The first heater element is configured as a first TFC element to coarsely adjust a fly-height of the magnetic-recording head with respect to the magnetic recording disk. The ECSE is configured to detect a contact with the magnetic-recording disk, and to function as a second heater element that is configured as a second TFC element to finely adjust the fly-height. The first heater element is configured with a first stroke-length larger than a second stroke-length of the second heater element for adjusting the fly-height.

Abstract: A disk drive is disclosed comprising a head actuated over a disk and a fly height actuator operable to control a fly height of the head in response to a fly height control signal. A touchdown operation is executed to set an operating fly height control signal by adjusting the fly height control signal until the head contacts the disk. A fly height calibration track is then read to set a fly height reference. When calibrating the operating fly height control signal, the fly height calibration track is read and the operating fly height control signal is adjusted in response to the fly height reference. When the adjusted operating fly height control signal is invalid, the touchdown operation is re-executed to reset the operating fly height control signal and then the fly height calibration track is read to reset the fly height reference.

Abstract: A data storage device is disclosed comprising a non-volatile memory and control circuitry comprising an interface operable to receive a supply voltage, and a capacitor. An operating voltage regulator converts the supply voltage into an operating voltage used to operate the non-volatile memory. The supply voltage is used to charge the capacitor to a capacitor voltage higher than the supply voltage, and during a power failure, a backup voltage regulator converts the capacitor voltage into a backup voltage substantially equal to the supply voltage. The operating voltage regulator converts the backup voltage into the operating voltage used to operate the non-volatile memory.

Abstract: A data storage library is described including a plurality of tape cartridges wherein each of the tape cartridges possesses an auxiliary radio frequency memory device in which auxiliary digital data is stored. The library also includes at least one drive disposed substantially within the library capable of transferring user data to and from one of the tapes. The library further includes at least one auxiliary radio frequency memory device reader that capable of reading the auxiliary digital data and transmitting the auxiliary digital data to at least one designated location, the reader is independent of the at least one drive.

Abstract: The present disclosure describes apparatuses and techniques of improved sequential-access of storage media. In some aspects an indication that a media disk interface failed to read a sector of a sequential-read during a revolution of the media disk is received and the media disk interface is caused to attempt to read a next sector of the sequential-read subsequent the sector failed to be read during a same revolution of the media disk.

Abstract: Described are embodiments of an invention for customizing the range of acceptable write conditions to a tape of a tape cartridge that contracts or expands laterally based on environmental conditions. The tape drive utilizes servo information to determine if the tape has expanded or contracted from the nominal dimension and to determine the magnitude of the expansion or contraction. In the case of expansion, the magnitude of the determined expansion and the stored maximum amount of contraction must be below a predetermined threshold value to allow a write. In the case of contraction, the magnitude of the determined contraction and the stored magnitude of expansion must be below the same predetermined threshold value to allow a write. If the determined magnitude of contraction or expansion is greater than the stored magnitude of contraction or expansion, respectively, then the new extreme is stored.

Abstract: A computer-implemented method, apparatus and computer-program product for writing data to a tape data storage medium. The method comprises providing a system service that an application invokes to handle data synchronization events associated with writing a group of files to the tape medium; keeping track of the files and data blocks in each file while writing the files to the tape medium based on file boundaries; and responsive to a data writing failure, invoking the system service to determine the files affected by the data writing failure.

Abstract: A tape edge sensor system for detecting lateral movement of a storage tape includes a first photo-emitter, a first photo-detector positioned to receive a first light signal from the first photo-emitter, a first aperture disposed between the first photo-emitter and the first photo-detector, and a feedback system connected to the first photo-emitter and the first photo-detector. The first aperture defines a first region at a first tape edge through which the first light signal is received by the first photo-detector with the storage tape blocking a portion of the first light signal. The feedback system determines the first photo-detector's signal amplitude and adjusts the first light signal such that the first photo-detector signal amplitude is within a first average amplitude range. A tape edge sensor system using compensating photo-interrupters is also provided.

Abstract: In various embodiments, systems and methods to detect signal irregularity caused by defects in the read/write head element are disclosed. In some embodiments, an exemplary system comprises a memory and a processor. The processor is coupled to the memory and is configured to implement a filter module and a detector module. The filter module is configured to generate a test waveform based on data read from a medium by a storage device head to be tested. The detector module is configured to generate a signal quality value based on a property of at least a portion of the test waveform, compare the signal quality value to an event threshold, and generate an event indicator based on the comparison, the event indicator indicating possible instability of the storage device head.

Abstract: Disclosed is a disk drive that is operable with a host computer that includes a printed circuit board assembly (PCBA) having a system on a chip (SOC). The disk drive comprises: a hard disk drive assembly (HDA); and a non-volatile semiconductor memory (NVSM). The NVSM is located within a preamplifier of the HDA and is couplable to the SOC of the host computer. The NVSM is configured to store configuration data for disk drive operation. The configuration data is configured to be retrieved by the SOC for controlling disk drive operations.

Abstract: Apparatus and methods for performing defect scanning on a disk drive which includes a disk constructed to have tracks written on the disk for storing data. Test data is concurrently written in more than one track on the disk and the data written to the more than one track is read to detect defects on the disk.

Abstract: Disclosed is a disk drive that is operable with a host computer that includes a printed circuit board assembly (PCBA) having a system on a chip (SOC). The disk drive comprises: a hard disk drive assembly (HDA); and a non-volatile semiconductor memory (NVSM). The NVSM is located in the HDA and is couplable to the SOC of the host computer. The NVSM is configured to store configuration data for disk drive operation. The configuration data is configured to be retrieved by the SOC for controlling disk drive operations.

Abstract: A disk drive is described with a single servo master timer that is used to control timing critical signals such as servo gate, SAM windows, channel power save, PREAMP power save and so on. The master timer is adjusted to compensate for SAM detection errors (early, late or missed) and provides improved servo timing quality. In an embodiment the adjustable master timer can be selectably clocked by either the DLC/DSW clock or the system clock.

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of non-circular servo tracks for defining a plurality of substantially circular tracks. Each non-circular servo track comprises a plurality of servo sectors defining a plurality of servo wedges. The head is positioned at a first offset relative to a first circular track and a relationship of servo bursts for each servo wedge is first generated. The head is positioned at a second offset relative to the first circular track and the relationship of the servo bursts for each servo wedge is second generated. For each servo wedge, a selection is made between the first generated relationship at the first offset and the second generated relationship at the second offset, and the servo bursts at the selected offset are evaluated to generate a track squeeze indicator.

Abstract: Embodiments described herein provide for robust servo patterns that comply with planarization constraints and also allow use of a single master template for manufacture of both the front and back of a magnetic disk. Planarization constraints are met because only a portion of servo data is hard patterned on the magnetic disk and the hard patterned servo data areas comply with planarization constraints. The servo pattern has two symmetrical servo write assist patterns, one on each side of a central burst pattern. The servo sync, SAM, track-ID, sector-ID, and/or RRO values can be written magnetically by the write head onto these servo write assist patterns after the completion of the planarization process. The symmetric design of the servo pattern allows both a left-to-right and a right-to-left servo write and read back, thereby enabling use of a single master template in magnetic disk manufacture.

Abstract: Approaches for a hard-disk drive (HDD) comprising a head slider comprising a thermoelectric embedded contact sensor. The thermoelectric embedded contact sensor may comprise a first and second conductive lead and a metallic component. The metallic component has a different Seebeck coefficient than the first and second conductive leads. A thermoelectric voltage across the metallic component is used to measure the distance between a head slider and a magnetic-recording disk without supplying an electrical current from a hard-disk drive to either of the first conductive lead or the second conductive lead.

Abstract: A magnetic recording system including follows: a recording head, a recording medium that includes a first recording medium layer, a second recording medium layer, and a substrate. The magnetic recording system includes an electric field applying device applying an electric field and a magnetic field applying device applying a magnetic field to the recording medium, a movement mechanism that moves them to an arbitrary position. The magnetic recording system has a function of controlling an applying direction of at least one of the electric field applying device and the magnetic field applying device, and the recording head is arranged at a position facing the recording medium.

Abstract: Certain embodiments of the present invention are directed to magnetic-tape drives that employ data-set-multiplexing magnetic-tape formats in order to achieve compatibility in magnetic-tape formats with respect to a variety of different magnetic-tape-drive tape-head configurations and dimensions. While previous and current magnetic-tape drives employ magnetic-tape formats that feature linear sequences of data sets along the tracks that are read or written during a single pass, or wrap, magnetic-tape drives of the present invention feature magnetic tape that contains data formatted according to a data-set-multiplexing magnetic-tape format, the data-set-multiplexing magnetic-tape format including, for each multiple-track wrap within a band, two or more parallel sequences of data sets written to the multiple tracks of the multiple-track wrap.

Abstract: Disk drives with preamp rotational parameter control (RPC) using standard digital serial interface lines to the preamp are described. The standard serial interface lines are used to generate a special signal pattern that does not follow the serial communication protocol. The special signal pattern is used to implement RPC when doing so will not interference with other signals, preferably in the read/write recovery gap between the data and the servo field in a standard track format. A value of a selected preamp parameter can be incremented or decremented by one LSB during the read/write gap time in each servo sector as the disk rotates. Embodiments of the invention allow fly-height and write driver parameters to be varied inside of a single disk revolution. Embodiments are described that include two or four parameters in the set, which allows for multiple updates of each parameter per revolution of the disk.

Abstract: A servo system according to one embodiment includes a servo control configured to: determine position error between a magnetic head and a desired position related to at least one defined servo track on a longitudinal tape based on at least one servo signal; calculate a first average position of the magnetic head while the longitudinal tape is moved in a first direction; calculate a first offset of the magnetic head while the longitudinal tape is moved in the first direction based on a target position and an assumption that the first average position of the magnetic head occurred when the tape was at a top-most position or a bottom-most position of a supply reel; and operate an actuator to position the actuator substantially at the target position using the first offset and the first average position.

Abstract: A voltage booster is disclosed comprising an input for receiving an input voltage Vin, a first charging capacitor C1, a second charging capacitor C2, and an output capacitor Cout. The output capacitor Cout is charged to four times Vin by connecting C1 in parallel with Vin to charge C1 to Vin, after charging C1 to Vin, connecting C2 in parallel with Vin plus C1 to charge C2 to twice Vin, after charging C2 to twice Vin, connecting C1 in parallel with Vin to recharge C1 to Vin, and after recharging C1, connecting Cout in parallel with Vin plus C1 plus C2 to charge Cout to four times Vin.

Abstract: A channel circuit includes a reader, a decoder, a prediction module, and a seek module. The reader reads data written in a medium. The decoder performs iterative decoding of the read data. The prediction module predicts whether an early read is possible or not without waiting for arrival of the read data. The seek module continuously initiates a seek when the prediction module predicts that the read is possible.

Abstract: An apparatus includes, in at least one aspect, a plurality of buffers and circuitry configured to store encoded data in one buffer of the plurality of buffers concurrently with storing other data in another buffer of the plurality of buffers and to write the stored encoded data from the one buffer to a storage device concurrently with storing encoded other data in the other buffer, replacing the stored other data in the other buffer.

Abstract: A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and control circuitry coupled to the read/write head and configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The control circuitry comprises a disk controller and read channel circuitry, with the read channel circuitry comprising a read channel memory. The control circuitry is further configured to selectively permit the disk controller to access the read channel memory. For example, the disk controller may be permitted to access the read channel memory only when the read channel circuitry is not performing a read operation.

Abstract: A system including a weighting function module, a frequency sensor module, and a control module. The weighting function module is configured to receive a plurality of samples of data, the data having been obtained based on a head having read the data from a storage medium while the head was at a given height above the storage medium, and to apply a weighting function to the plurality of samples to generate weighted samples. The frequency sensor module is configured to estimate, based on the weighted samples, (i) a first magnitude of a first frequency component, and (ii) a second magnitude of a second frequency component. The control module is configured to estimate, based on the first magnitude and the second magnitude, the height of the head above the storage medium.