Abstract: Method and apparatus for data security in a data storage device. In some embodiments, a first version of firmware is installed in a memory of the device. The firmware is used by a programmable processor to control accesses to a rotatable data recording medium on which is written pre-recorded servo positioning data used to position a data transducer. A newer, second version of the firmwave is subsequently installed in the memory to replace the first version of firmware. The second version of the firmware includes an instruction to corrupt a selected portion of the servo positioning data on the medium in order to authenticate the second version of the firmware. During a subsequent initialization of the device, host access is granted based on detection of the corruption of the selected portion of the servo positioning data.

Abstract: A computer-implemented method, according to one embodiment, includes, performing anti-aliasing filtering on each of a plurality of symmetrical square wave signals, each symmetrical square wave signal having a frequency that is a different fraction of a frequency of a data read clock. The filtered symmetrical square wave signals are passed through a band pass filter. An amplitude of each of the symmetrical square wave signals is measured after the band pass filtering. In response to the amplitudes of the symmetrical square wave signals being within a predefined range, anti-aliasing settings used during the anti-aliasing filtering are stored. In response to the amplitudes of the symmetrical square wave signals being outside the predefined range, the anti-aliasing settings are changed.

Abstract: In certain embodiments, an apparatus may comprise a first output driver connected to a first output via a first trace and a second output driver connected to a second output via a second trace. The first output driver may be configured to output a first drive signal to the first output to drive the first output and the first drive signal may cause first induced noise in the second trace. Further, the second output driver may be configured to output a second drive signal based on the first drive signal where the second drive signal may reduce the magnitude of the first induced noise at the second output.

Abstract: There is disclosed herein charge-mode circuitry for use in a comparator to capture a difference between magnitudes of first and second input signals, the circuitry comprising: a tail node configured during a capture operation to receive a charge packet; first and second nodes conductively connectable to said tail node along respective first and second paths; and control circuitry configured during the capture operation to control such connections between the tail node and the first and second nodes based on the first and second input signals such that said charge packet is divided between said first and second paths in dependence upon the difference between magnitudes of the first and second input signals.

Abstract: According to one embodiment, there is provided a disk apparatus including a disk medium and a controller. The disk medium is able to store a signal with three levels in a track. The track includes a first subtrack and a second subtract. The second subtrack is adjacent to the first subtract. The controller performs a first operation based on a selected level among the three levels, a first bit written in the first subtract corresponding to the selected level, and a second bit written in the second subtrack corresponding to the selected level. The first operation is an operation to correct displacement between a write position of a third bit in the first subtrack and a write position of a fourth bit in the second subtrack in a circumferential direction of the disk medium.

Abstract: A memory system includes a plurality of channels; a plurality of semiconductor memory devices connected to the channels; and a controller that controls the semiconductor memory devices through the channels, wherein the controller writes program data in a first semiconductor memory device of the plurality of semiconductor memory devices, and wherein, when the writing of the program data fails, the program data is temporarily stored in a page buffer unit of a second semiconductor memory device of the plurality of semiconductor memory devices connected to a channel other than the channel corresponding to the first semiconductor memory device.

Abstract: Implementations disclosed herein provide a method comprising iteratively reading data from a failing media sector prior to a an error minimization operation, analyzing read data at each iteration using an error minimization operation to determine sections of read data as good data, storing the good data in a buffer during each iteration, and using the good data as input for the read data during a subsequent error retry operation. In another implementation, the method further comprises comparing new read data with stored good data in the buffer, and replacing the stored good data with the new read data if the new read data has a higher quality than the stored good data.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a magnetic head, and a processor. The magnetic head includes a first reproducing element portion and a second reproducing element portion. The processor is configured to acquire a first signal and a second signal, and to output an output signal according to either one of the first signal and the second signal. The first signal is obtained by reproducing information recorded on a first recording region by the first reproducing element portion. The second signal is obtained by reproducing the information recorded on the first recording region by the second reproducing element portion.

Abstract: Implementations described and claimed herein includes a storage device comprising a plurality of readers, including a first subset of readers configured to read a first subset of tracks and a second subset of readers configured to read a second subset of tracks, the first subset of tracks being wider than the second subset of tracks. In another implementation, the readers in the first subset of readers are wider than the readers in the second subset of readers. The wider readers may be configured to recover servo information and the narrow readers may be configured to recover data information. The storage devices may include two-dimensional magnetic recording, conventional perpendicular magnetic recording, shingled magnetic recording, multi-sensor magnetic recording, and interlaced magnetic recording.

Abstract: This disclosure describes codes and techniques for magnetic recording. The coding schemes decrease bit error rates by decreasing total transitions in the encoded binary data compared to conventional codes. Additionally, instead of relying on a single coding scheme, an encoder and decoder are configured to switch between different coding schemes. By so doing, a variety of the coding schemes allows the encoded binary data to have a smaller bit error rate than a single coding scheme and have a maximum run-length less than or equal to a maximum run-length limitation of a magnetic disk.

Abstract: The invention provides a signal processing device, including: an extraction section that extracts, from an input digital signal, a decoding target signal at an extraction timing that has been determined as a timing for extracting the decoding target signal; a decoding section that decodes the decoding target signal by estimating, by a maximum likelihood decoding, a candidate for a decoding result of the decoding target signal extracted by the extraction section and detecting a maximum likelihood decoding result; and an adjustment section that adjusts the extraction timing using a likelihood of the candidate for the decoding result estimated by the decoding section.

Abstract: A method, computer program product, and system for dividing a file and writing the file to a plurality of tapes in a tape library system comprising a plurality of tape apparatuses. A request to write a file to a plurality of tapes is received. The file comprises data. A number of available tapes is predicted with respect to a number of drives available at a time when the file requested to be written is written to the plurality of tapes. The data of the file is divided into a predetermined number of segments to reduce a time period for reading the file. The predetermined number of segments is based on the predicted number of tape drives. The data segments are written to the available tape drives.

Abstract: A storage device includes a transducer head including a first write element configured to write data at a first write width and a second write element configured to write data at a second write width less than the first write width. According to one implementation, the first write element writes data at a first linear density and to alternating data tracks and the second write element writes data at a second linear density and to data tracks interlaced with the alternating data tracks.

Abstract: This application includes systems and techniques relating to storage devices, such as a device including: a first read channel to process a first input signal obtained from a storage medium using a first read head; a second read channel to process a second input signal obtained from the storage medium using a second read head, which is offset from the first read head in each of two dimensions; a single digital timing loop configured to control interpolation of timing of sampling for first and second analog to digital converters in the first and second read channels; and a two dimensional equalizer coupled with output lines of the first and second read channels; the device being configured to account for a fractional timing difference between the first input signal and the second input signal, the fractional timing difference being a fractional amount of a single clock cycle of the device.

Abstract: An apparatus and method involves a writer configured for heat-assisted magnetic recording of data to a magnetic storage medium. A controller is coupled to the writer. The controller and writer are configured to write data to a plurality of concentric bands of the medium each comprising a plurality of partially overlapping narrow data tracks and a wide track. The wide tracks of successive bands are positioned adjacent to one another with no intervening narrow data track therebetween.

Abstract: In response to a command to update a target track, two tracks or more are concurrently read. The two tracks or more tracks include a top track that partially overlaps the target track. Data of the top track is stored in a memory, and the update data is written over at least part of the target track. The stored data is written on the recording medium over the top track or at a different location.

Abstract: Systems and methods relating generally to determining flaws on a storage medium.

Abstract: An AC signal having a specified frequency and a DC offset voltage is applied to a slider substrate or a magnetic recording medium. A low- or non-modulation interface is defined between the slider and medium. In response to applying the AC signal, an oscillation in an electrostatic force occurs between the slider and the medium at the specified frequency, which causes an oscillation in thermal sensor signal at the slider, which oscillates at the specified frequency. A heater of the slider is adjusted to decrease spacing between the slider and medium during oscillation of the electrostatic force. For each heater adjustment, thermal sensor resistance is measured over a specified number of medium revolutions. Head-medium contact is detected using one of an amplitude of a harmonic of the thermal sensor signal and a summation of amplitudes of all frequency components at the specified frequency.

Abstract: A computer-implemented method, according to one embodiment, includes: receiving a first output signal from a write driver, the write driver having an operating voltage applied thereto, receiving a second output signal from a comparator circuit, the comparator circuit having a reference voltage applied thereto, comparing a voltage of the first output signal with a voltage of the second output signal, and detecting a high resistance condition in response to determining that the voltage of the first output signal is less than the voltage of the second output signal. According to the present embodiment, the high resistance condition indicates open and/or partially open circuitry in the write driver. Moreover, the operating voltage is equal to the reference voltage. Other systems, methods, and computer program products are described in additional embodiments.

Abstract: Systems and methods are disclosed for data processing, and more particularly for equalizing a data signal during both real time (i.e., on the fly) and retry operation. The system may include a first equalizer circuit operable to equalize a first sample set, and a second equalizer circuit operable to equalize a second sample set. The system may include a third equalizer circuit operable to equalize a summed data set to yield a third equalized output. The system may include a summation circuit connected to the first equalizer circuit, the second equalizer circuit, and a switch circuit. The summation circuit is operable to sum at least the first equalized data set and the second equalized data set to yield the summed data set. The switch circuit selectively provides the third equalized data set to the summation circuit.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a recording unit and a reproducing unit. The magnetic recording medium includes a first track and a second track, the first track extending in a first direction, the second track extending in the first direction and being arranged with the first track in a second direction intersecting the first direction. The first track includes first and second sub-tracks extending in the first direction. The second track includes third and fourth sub-tracks extending in the first direction. The second sub-track is disposed between the first and fourth sub-tracks. The third sub-track is disposed between the second and fourth sub-tracks. The recording unit records information in the first and second tracks. The reproducing unit reproduces first information recorded in the first track. The reproducing unit reproduces second information recorded in the second track.

Abstract: Embodiments of the present inventions are related to systems and methods for data processing, and more particularly to systems and methods for reducing inter-track interference in relation to processing data retrieved from a storage medium.

Abstract: The present disclosure describes systems and techniques relating to storage devices, such as storage devices that employ Two Dimensional Magnetic Recording (TDMR). According to an aspect of the described systems and techniques, a device includes: a first read channel to process a first input signal obtained from a Two Dimensional Magnetic Recording (TDMR) storage medium using a first read head, wherein the first read channel includes a first analog to digital converter (ADC); a second read channel to process a second input signal obtained from the TDMR, storage medium using a second read head, wherein the second read channel includes a second ADC; and a single digital timing loop (DTL) for both the first read channel and the second read channel, wherein the single DTL is configured to control interpolation of timing of sampling for the first and second ADCs.

Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for detecting patterns in a data stream. As an example, a data processing system is discussed that includes a sync mark detection circuit and a sync quality output circuit. The sync mark detection circuit is operable to identify a predefined pattern in a received data set, where identification of the predefined pattern results is asserting a sync found output, and where a preamble pattern precedes the predefined pattern in the received data set. The sync quality output circuit is operable to provide a sync mark quality metric indicating a similarity between the preamble pattern and the received data set within a region preceding the predefined pattern.

Abstract: A detector (22) detects an event. First and second time-to-digital converters (TDCs) (70, 72) generate first and second time stamps (TS1, TS2) for the detection of the event. The first TDC and the second TDC are both synchronized with a common clock signal (62) that defines a fixed time offset between the second TDC and the first TDC. An autocalibration circuit (120) adjusts the first TDC and the second TDC to keep the time difference between the second time stamp and the first time stamp equal to the fixed time offset between the second TDC and the first TDC. The detector may be a detector array, and trigger circuitry (28) propogates a trigger signal from a trigger detector of the array of detectors to the first and second TDC's. Skew correction circuitry (132, 134, 136, 142, 60, 162) adjusts a timestamp (TS) based on which detector is the triggering detector.

Abstract: A data processing system includes an equalizer circuit operable to equalize digital data according to tap coefficients to yield equalized data, a tap coefficient adaptation circuit operable to adapt the tap coefficients based at least in part on a scaled error signal, a data detector operable to apply a data detection algorithm to the digital data to generate hard decisions and soft decisions, an error calculation circuit operable to calculate an error signal based on the equalized data and on the hard decisions, and a scaling circuit operable to scale the error signal based on the soft decisions to yield the scaled error signal.

Abstract: A system for writing data to overlapping physical tracks of a shingled magnetic record (SMR) hard disk drive (HDD) and a method for creating a logical disk from overlapping physical tracks of the SMR HDD. The system comprises a write header and a memory identifying the overlapping physical tracks which are accessible through the logical disk. The physical tracks are spaced from each other by at least the width of the write header. The method comprises mapping in a memory the logical disk to writeable tracks of the overlapping physical tracks, the writeable tracks spaced from each other by at least the width of the write header.

Abstract: A reader failover system and method are described for a data storage system. At least two reader systems, including a first reader element and a second reader element, situated on the same head, are employed to read a magnetic storage medium. In an aspect, the head is a two-dimensional magnetic recording (TDMR) head. Control circuitry detects when the first reader system provides less than a predetermined performance or fails, and thereafter causes the second reader system, but not the first reader system, to read the magnetic storage medium. In an aspect, a buffer stores a first reader element signal until the control circuitry detects whether or not the first reader element provides less than a predetermined performance or fails. In an aspect, when a reader element fails, data recovery is performed, and all of, or a majority of, the media continues to be readable, improving the data storage system robustness.

Abstract: According to one embodiment, a microwave-assisted magnetic recording head includes a SIL formed either in an area outside a FGL in a track width direction or in an area outside a FGL in a depth direction perpendicular to an air bearing surface of the FGL. An area between the SIL and the FGL can be enlarged, and an intermediate layer can be formed therebetween such that an area in which the intermediate layer contacts the FGL can be enlarged as well.

Abstract: Systems, methods, devices, circuits for data processing, and more particularly to systems and methods for processing skew tolerant processing of data derived from multiple read heads.

Abstract: Method and apparatus for decoding data, such as from a rotatable magnetic recording medium. In accordance with some embodiments, a plurality of sensors is provided, with each sensor configured to generate a sense signal from an adjacent pattern. A processing circuit is configured to decode data from the adjacent pattern using the generated sense signals.

Abstract: Technologies are described herein for utilizing multiple, wide readers to read narrow data tracks on a magnetic recording media in a storage device. A system for reading a data track on a magnetic recording media comprises a plurality of reader elements and a multi-reader decoder module operably connected to the plurality of reader elements. Each of the reader elements is configured to read a magnetic signal from the magnetic recording media. Each reader element may be wider than a width of the data track on the recording media. The multi-reader decoder module is configured to receive a read signal from each of the reader elements, and decode the data on the data track based on the read signals from the reader elements.

Abstract: According to various embodiments, a method for reading data from a storage medium using a reader may be provided. The method may include: reading a first signal with a reader head of the reader at a first position of the storage medium; reading a second signal with a reader head of the reader at a second position of the storage medium; and determining data stored at a pre-determined position of the storage medium based on the first signal and based on the second signal.

Abstract: In accordance with one embodiment, a computer program product includes a computer readable storage medium having computer readable program code that is readable and/or executable by a processor to: receive a signal including precoded data read from a magnetic tape medium and pass the signal through a soft detector to calculator first soft information about each bit of the signal and to provide adaptive compensation for the precoded data, send the first soft information to a soft decoder, pass the signal through the soft decoder to calculate second soft information about each bit the signal, and send the second soft information to the soft detector, wherein the precoded data is passed through at least one precoder prior to being written to the magnetic tape medium via a precoder that applies 1/(1?D2) to bits of data, where D is delay corresponding to bit duration

Abstract: Records or filemarks read from data segments are aggregated into at least one single data segment. The records and the filemarks are padded at an end of the one single data segment, such that the padding of the end of the one single data segment is less than padding of the one of the records and filemarks in the plurality of data segments.

Abstract: In one embodiment, a method includes passing a signal through a noise whitening filter, passing the signal through a soft detector to calculate first soft information, passing the signal through the soft decoder to calculate second soft information based on the first soft information, and sending the second soft information to the soft detector, wherein the noise whitening filter is configured to process the signal according to the following transfer polynomial: W(D)=1?(p1D+ . . . p1D?), where p1 . . . p? are noise whitening coefficients, D is delay corresponding to bit duration, and a transfer polynomial of the tape channel is F(D)=1+f1D+ . . . +fLDL, wherein L represents a memory length of the tape channel, and wherein ? represents a memory length of the noise whitening filter. Other methods, systems, and computer program products are described in more embodiments.

Abstract: A Dynamic Wave-Shaping (DWS) write driver for use in a preamp in a disk drive is described. The DWS write driver includes a Dynamic Current Booster (DCB) that adds a current component (WDCB) to the standard write driver signal (including overshoot) that is a function of the bit spacing in the write data input waveform supplied to the write driver. The invention allows dynamic control of the bit-pattern dependent overshoot amplitude without requiring significant preamp overhead. Embodiments of the Dynamic Current Booster include a programmable analog feed-forward timer at the preamp level. The boost current amplitude is a function of the time between the transitions that represent bits. In embodiments, the polarity of the boost current WDCB can be programmed to be positive or negative.

Abstract: A data storage device is disclosed comprising a disk comprising a plurality of data tracks, and a head comprising a first read element and a second read element. A first data track is read using the first read element to generate a first read signal, and the first read signal is sampled to generate first signal samples. A first branch metric is generated in a first trellis sequence detector when detecting a first data sequence based on one of the first signal samples. A second data track adjacent the first data track is read using the second read element to generate a second read signal, and the second read signal is sampled to generate second signal samples. A second branch metric is generated in a second trellis sequence detector when detecting a second data sequence based on one of the second signal samples and the first branch metric.

Abstract: A method and system for providing format savings in data sectors. The method includes receiving a signal outputted from an analog-to-digital conversion circuit. The method further includes shifting a signal phase of the signal based at least upon a corrected phase at an output of a phase loop and a phase measured when the signal was digitally sampled by the analog-to-digital conversion circuit. The method also includes adjusting a gain of the signal based at least upon a current gain loop correction and a gain correction made when the signal was digitally sampled by the analog-to-digital conversion circuit. Additionally, the method includes adjusting the signal based at least upon an output of a current offset correction and an offset correction made when the signal was digitally sampled by the analog-to-digital conversion circuit. The method also includes outputting an adjusted signal to a sync mark detector.

Abstract: A semiconductor integrated circuit device has a p-type substrate to which a ground voltage is applied and a floating-type NMOSFET which is integrated on the p-type substrate and to which a negative voltage lower than the ground voltage is applied. The floating-type NMOSFET includes an n-type buried layer buried in the p-type substrate, a high voltage n-type well formed on the n-type buried layer and floats electrically, a p-type drift region formed in the n-type well, an n-type drain region and an-type source region formed in the p-type drift region, and a gate electrode formed on a channel region interposed between the n-type drain region and the n-type source region. The high voltage n-type well includes an n-type tunnel region, with a higher impurity concentration than that of the high voltage n-type well, inside a peripheral region formed so as to surround the p-type drift region.

Abstract: Methods for measuring media performance associated with adjacent track interference are provided. One such method includes iteratively writing data to a target track for each of a plurality of n frequencies, measuring a first signal amplitude and a first noise for each of the n sectors on the target track, writing an aggressor track pattern proximate the target track, measuring a second signal amplitude and a second noise for each of the n sectors on the target track, calculating a weighted sum for each of the signal amplitude measurements for each of the plurality of n frequencies, and calculating a weighted sum for each of the noise measurements for each of the plurality of n frequencies, and repeating the writing the aggressor track pattern, the measuring the second signal amplitude and the second noise, and calculating the weighted sums for preselected numbers of times.

Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for detecting patterns in a data stream. In one case, a data processing system is disclosed that includes: a pattern detector circuit operable to generate a pattern value based upon a comparison of a defined pattern to a first portion of a received input; and a comparator circuit operable to compare the pattern value to an adapted threshold, and to selectively assert a pattern found signal based at least in part on the comparison of the pattern value and the adapted threshold, where the adapted threshold is adjusted based at least in part on a noise component of a second portion of the received input.

Abstract: A method for detecting an information pattern includes obtaining a first sample stream and a second sample stream. The first sample stream and the second sample stream are obtained by sensing recorded information at a target location of a storage medium using a first sensor and a second sensor, respectively. A first metric is computed by comparing the first sample stream to a reference pattern representative of a target information pattern to be detected. A second metric is computed by comparing the second sample stream to the reference pattern. A combined metric is computed by combining the first metric and second metric using a weighting function. The target information pattern is detected using the combined metric.

Abstract: An implementation of a system disclosed herein provides a method of deferring decoding of a data sector received at a read channel of a storage device, in response to determining that a data sector cannot be decoded by a first decoder and storing the data sector for further processing by a second decoder.

Abstract: The disclosure is directed to a system and method of a system and method for determining fundamental bit cell duration of a data record, which can be used for pattern-dependent write (PDW) current control. According to various embodiments of the disclosure, at least a first portion of a data record is fed through a plurality of delay units. A binary output of each delay unit is stored in at least one register when the delay units have received the first portion of the data record. The register contents are then decoded to determine fundamental bit cell duration of the data record based upon the stored binary outputs.

Abstract: Systems and method relating generally to data processing, and more particularly to systems and methods for utilizing multiple data streams for data recovery from a storage device.

Abstract: According to at least one embodiment, a magnetic disk apparatus includes a disk, a random number generator, a determination module, and a refresh module. The disk includes a plurality of tracks. A random number generator generates a random number within a range of N integers in accordance with writing to a first area of a first track of the plurality of tracks. A determination module determines whether the generated random number includes a predetermined number. A refresh module refreshes a second area of a second track near the first track based on a result of determination of the determination module. The second area corresponds to the first area.

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

Abstract: Technologies are described herein for detecting adjacent track interference in a storage device using a size-adjustable sliding window. A value for an inter-track interference factor associated with at least one adjacent track is determined for a first area of a data track of the storage device. The first area may encompass a plurality of sectors of the data track. Next, it is determined whether the value of the calculated inter-track interference factor is greater than a threshold value, and if so, an indication of inter-track interference corresponding to the first area is stored in the storage device.

Abstract: A system and method for power management in a hard disk drive (HDD) assembly incorporating two or more read sensors includes directing a read/write head to follow a track; depowering one or more read sensors and readpath circuits associated with the read sensors; reading an analog readback signal through the first read sensor; processing the signal through an analog front-end to generate an input signal; sampling the input signal through an analog to digital converter at a first frequency to generate a first sampling signal; sampling the input signal through a second analog to digital converter at a second frequency to generate a second sampling signal; and generating a digital output signal from either or both sampling signals at a third sampling frequency through a digital signal processor. The method may additionally comprise adjusting a sampling frequency when power level reaches a threshold.