Abstract: According to the embodiment, a controller of a magnetic disk apparatus acquires a first amplitude and a first phase of a first read waveform and a second amplitude and a second phase of a second read waveform by demodulating the first/second read waveforms. The first read waveform is a read waveform of a first burst pattern. The second read waveform is a read waveform of a second burst pattern. The controller acquires weights on the basis of the first amplitude, the second amplitude, the first phase, and the second phase. The controller corrects an initial phase of each of the first read waveform and the second read waveform by calculating a weighted average using the weights, the first phase, and the second phase. The controller executes positioning of the magnetic head on the basis of the corrected first read waveform and second read waveform.

Abstract: According to an embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, and a control circuit. The magnetic disk has a plurality of first storage regions disposed in the radial direction. The recording method is changeable for each of the plurality of first storage regions. The control circuit operates such that, when having received a first command instructing to change the recording method of one first storage region out of a plurality of first storage regions, the control circuit changes the recording method of the one first storage region in accordance with the first command, and moves a magnetic head onto the second storage region before receiving a second command.

Abstract: A magnetic recording/reproducing device includes a magnetic recording medium, a plurality of assisted magnetic recording heads, and a processor configured to write data onto the magnetic recording medium according to a first type of magnetic recording or a second type of magnetic recording and select one of the assisted magnetic recording heads for recording based on at least one of assist power and application time of the assist power when assisted magnetic recording is performed.

Abstract: According to an embodiment, a controller of a magnetic disk apparatus moves a magnetic head to a first track being one of tracks on a magnetic disk. The controller acquires, in a servo sampling cycle, a positioning error amount of the magnetic head with respect to the first track. The controller executes an access to the first track by the magnetic head after a positioning error amount equal to or less than a first threshold is continuously acquired a first set number of times. The controller obtains a frequency estimation value by estimating a frequency of residual vibration of the magnetic head due to movement of the magnetic head to the first track and obtains an amplitude estimation value by estimating an amplitude of the residual vibration. The controller updates the first set number of times on the basis of the frequency estimation value and the amplitude estimation value.

Abstract: According to one embodiment, a disk device includes a disk-shaped recording medium, a magnetic head including a write head, a read head, and a heater, and a controller including a reference signal generator outputting a reference signal having a constant voltage amplitude at the same frequency as a high-frequency component of a gap measurement signal recorded in the recording medium, a measurer measuring a component amplitude of a reproduced signal of the gap measurement signal and an amplitude of the reference signal, and a heater controller controlling a power value of heater power supplied to the heater based on the measured values of the component amplitude and the amplitude of the reference signal.

Abstract: A magnetic recording and reproducing device includes a magnetic recording medium including a protective layer that is exposed to an enclosed interior volume of the magnetic recording and reproducing device, which contains oxygen and helium, a magnetic head including a heat assist element that is also exposed to the enclosed interior volume, the magnetic head configured to record data onto the magnetic recording medium, and an oxygen amount measurement unit configured to measure an oxygen amount in the enclosed interior volume.

Abstract: According to one embodiment, a magnetic disk device comprising a magnetic head expanding to the magnetic disk side with the generated heat of a heater, a flying height measurement unit measuring a flying height of the magnetic head, based on a read signal of the magnetic head for data for measuring flying height written to the magnetic disk, and a controller. The controller detects variation of a measurement value of the flying height measurement unit, based on change of “correspondence between a change amount of the supply power and a measurement value of the flying height measurement unit”.

Abstract: A magnetic disk device detects a shift of writing positions of a spiral pattern, corrects the regulation speed in a direction where the shift is canceled, and writes spiral patterns based on the corrected regulation speed.

Abstract: Various illustrative aspects are directed to a data storage device comprising a disk, a read/write head configured to read data from and write data to the disk, a laser diode (LD) coupled to a nearfield transducer configured to heat an area of the disk near the read/write head, a first resistive temperature detector (RTD), a second RTD, and one or more processing devices configured to: apply a laser bias to the LD during a write operation; obtain a plurality of differential signal measurements, based at least in part on a plurality of measurements from each of the first and second RTDs; and adjust the laser bias applied to the LD, based at least in part on comparing the plurality of differential signal measurements to a target value for the differential signal.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, and a controller including an offtrack write table, positioning the magnetic head, and registering an address at which data in a track is written and a positioning error of the magnetic head at the address for the track, in the offtrack write table. When writing data to a first sector, the controller corrects a positioning target position of the first sector, based on a positioning error of a second sector located on two tracks away in a radial direction from the first sector.

Abstract: A data storage device comprises a disk and a head having a read and write elements. A read heater is powered based on a dual heater ratio (DHR) to thermally adjust a spacing of the read element from a disk surface, and a write heater is powered based on the DHR to thermally adjust a spacing of the write element from the disk surface. A read spacing slope profile is determined comprising read touchdowns (TDs) over a range of DHRs, and a write spacing slope profile is determined comprising write TDs over the range of DHRs. An operating DHR of the head is set to be where the read spacing slope profile intersects the write spacing slope profile.

Abstract: A method for determining a fly height includes measuring a first differential voltage between a first head of a disk drive and a reference voltage with a first front end circuit, converting the first differential voltage to a first analog current signal with the first front end circuit, and converting the first analog current signal to a second differential voltage with a first back end circuit. The first front end circuit is coupled with the first head. The first back end circuit is coupled with the first front end circuit. The method further includes determining a first capacitance between the first head and a first disk of the disk drive based on the second differential voltage and determining the fly height between the first head and the first disk using the first capacitance.

Abstract: Methods, data storage devices, and computer-readable media for setting the flying height of a recording head are disclosed. A method may set a value of a control parameter of the recording head to force a predetermined location of the recording head to be a touchdown location. The method may involve incrementally moving the recording head toward a surface of a recording media, and, using a temperature sensor of the recording head, detecting an onset of touchdown at the touchdown location as the recording head is incrementally moving toward the surface of the recording media. The method may set the fly-height control power by backing off from an initial fly-height control power value, which may be a sum of a power level at which the onset of touchdown at the touchdown location was detected and a power corresponding to the value of the control parameter.

Abstract: A method, in accordance with one aspect of the present invention, includes writing, by a tape drive, data tracks to a data band of a magnetic tape having servo bands flanking the data band, the writing being performed using a magnetic head that is not designed for a format of the magnetic tape. An effective pitch of servo readers of the magnetic head used simultaneously during the writing matches a servo reader pitch specification of the format of the magnetic tape. An average effective pitch of write transducers of the magnetic head is greater than a data track pitch specification of the format of the magnetic tape.

Abstract: A data storage device or disk drive may include a plurality of regulators, a first voltage rail associated with a first regulator of the plurality of regulators, a second voltage rail associated with a second regulator of the plurality of regulators, wherein a switching frequency of the second regulator is greater than a switching frequency of the first regulator, the first voltage rail is associated with a higher voltage than the second voltage rail, or a combination thereof. The data storage device may include one or more processing devices configured to: determine a minimum switching frequency, identify a start time of a switching cycle for the first regulator, based at least in part on determining the minimum switching frequency; and, at or near the start time of the new switching cycle, couple the first regulator to the second regulator to initiate the switching cycle.

Abstract: The history record unit, in the non-volatile storage device, records recovery history information showing a history of the recovery process. The suspension control unit, when the recovery process' frequency specified based on the recovery history information exceeds a first reference frequency, restricts execution of the specific suspension process which is in response to a satisfaction of the suspension condition. Further, the suspension control unit, when the recovery process' frequency specified based on the recovery history information is lower than a second reference frequency, which is lower than the first reference frequency, under a situation where the specific suspension process' execution is restricted, cancels the restricting of the specific suspension process' execution.

Abstract: A piezoelectric (PZT) actuator assembly having a fixed-end and a hinged-end is provided. The assembly includes a first side electrode at the hinge-end, and a second side electrode at the fixed-end. The assembly includes a third piezoelectric layer including a top surface and a bottom surface disposed over the top surface of the second PZT layer. A fourth electrode is at least partially disposed on the top surface of the third PZT layer. The fourth electrode is connected to the second side electrode at the fixed-end.

Abstract: Various illustrative aspects are directed to a data storage device comprising a slider with a resistive temperature detector (RTD) having a first resistance electrically connected to a first amplifier and a plurality of controlled current sources and switches, and one or more processing devices configured to: control the switches to generate an alternating-bias signal having a first clock frequency for biasing the first resistance, modulate an input signal of the first amplifier using the first clock frequency to generate a modulated signal, demodulate an amplified modulated signal at an output of a second amplifier using the first clock frequency to generate a resistance detection signal, the second amplifier coupled to the first amplifier, and process the resistance detection signal to determine the first resistance and/or a change in value of the first resistance.

Abstract: A method involves determining a threshold error rate that will result on data stored on a magnetic disk surface of a disk drive being unrecoverable. The method also involves determining a seek velocity that will overwrite sufficient portions of the data such the data will exhibit at least the threshold error rate. The disk drive performs at least one traversal of the magnetic disk surface with a head of the disk drive that emits an erase field during the at least one traversal at the seek velocity. The at least one traversal sanitizes the data.

Abstract: Various illustrative aspects are directed to a data storage device comprising one or more disks; a spindle motor for rotating the one or more disks, wherein the spindle motor comprises a plurality of magnetic pole-pairs, and wherein the spindle motor is configured to operate in a plurality of modes, including at least a first mode and a second mode; and one or more processing devices configured to select a reference point for spindle motor interrupt service routines (ISRs), determine a delay time, wherein the delay time is based at least in part on a number of magnetic pole-pairs and a mechanical revolution period of the spindle motor, start a timer at a first ISR, and when the timer is equal to the delay time, switch operation of the spindle motor from the first mode to the second mode.

Abstract: Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position a selected head among one or more heads proximate to a corresponding disk surface of the one or more disks; and one or more processing devices. The one or more processing devices are configured to detect adjacent track interference (ATI) due to a write operation in an adjacent sector to a subject sector on the corresponding disk surface; and to generate a readback servo trajectory for the subject sector, based on a position error signal (PES) for the subject sector, a PES for the adjacent sector, and the ATI.

Abstract: Methods, systems, and devices for techniques for non-volatile data protection are described. As part of a power on operation, a non-volatile memory system may be configured to selectively stored data. For example, the memory system may determine whether a host system is authorized to access data stored in the memory system prior to a power off operation. If the memory system determines that the host system is authorized, the memory device may retain the data. If the memory system determines that the host system is not authorized, the memory system may erase all or a portion of the data. In some cases, the memory system may maintain a retain flag to determine whether the host system is authorized. Additionally or alternatively, the memory system may determine whether a password received from the host system is valid to determine whether the host system is authorized.

Abstract: A magnetic tape including a timing-based servo pattern, in which the magnetic tape is used in a magnetic tape device in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, and ?PNL of the timing-based servo pattern is 10.0% or less of a track pitch. A magnetic tape cartridge including the magnetic tape, and a magnetic tape device including a magnetic tape, in which a total number of data tracks is 8705 or more in conversion of a magnetic tape having a width of ½ inches, the magnetic tape includes a timing-based servo pattern, and ?PNL of the timing-based servo pattern is 10.0% or less of a track pitch are provided. The ?PNL indicates an amount of deviation of the timing-based servo pattern from linearity.

Abstract: A magnetic head includes a first servo reading element pair, a second servo reading element pair, and a plurality of magnetic elements. The first servo reading element pair consists of a first servo reading element and a second servo reading element, the second servo reading element pair consists of a third servo reading element and a fourth servo reading element, the first servo reading element and the third servo reading element are disposed on one end side of the plurality of magnetic elements and read one servo band of the pair of servo bands, and the second servo reading element and the fourth servo reading element are disposed on the other end side of the plurality of magnetic elements and read the other servo band of the pair of servo bands.

Abstract: A device of force sensing, which includes a rigid structure and force sensors. The rigid structure includes rigid blocks spaced apart, and a strain amplification area is formed between two adjacent rigid blocks, every two force sensors in four force sensors are used as a group, and two groups of the force sensors are selectively arranged corresponding to two of the mounting surfaces of the strain amplification area, the four force sensors are connected to form different bridge circuits.

Abstract: According to an embodiment, a magnetic disk is provided with a servo sector in which a preamble and a burst pattern are recorded. A recording frequency of the preamble is different from an even multiple of a recording frequency of the burst pattern. A controller determines a demodulation period of the burst pattern while a magnetic head passes through the servo sector. The controller acquires a first phase of a demodulation signal of the burst pattern and acquires first position information of the magnetic head, by demodulating the burst pattern in the demodulation period. The controller corrects the first position information on the basis of the first phase. The controller executes positioning control of the magnetic head on the basis of second position information that is post-correction first position information.

Abstract: Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position one or more heads proximate to a corresponding disk surface of the one or more disks; and one or more processing devices. The one or more processing devices are configured to apply a pre-bias current to the assistive energy emitter at a first value while the selected head is positioned proximate to one or more spiral patterns on the corresponding disk surface. The one or more processing devices are further configured to apply the pre-bias current to the assistive energy emitter at a boosted value while the selected head is not positioned proximate to the one or more spiral patterns, wherein the boosted value is greater than the first value.

Abstract: Various illustrative aspects are directed to a data storage device comprising data tracks N and N?1, and one or more processing devices, configured to identify, during a track write on the data track N, a write abort event based upon an expected risk for the data track N?1 exceeding a risk threshold, read one or more sectors of the data track N?1 and collect one or more corresponding sector metrics, verify the one or more sectors based upon the collected sector metrics, wherein the verifying comprises assigning each of the one or more sectors as one of a readable or a non-readable sector, and continue the track write on the data track N upon determining each of the one or more sectors is a readable sector, or recovering and relocating the data track N?1 based on determining at least one of the sectors is a non-readable sector.

Abstract: According to one embodiment, a disk device includes a rotatable magnetic disk, an actuator which supports and moves a head, a ramp which holds the head at an unloaded position, a motor which rotates the magnetic disk, and a controller which performs a load operation and a seek operation. When a radial travel speed of the head during the load operation is referred to as Vr1, a circumferential travel speed of the head is referred to as Vt1, a radial travel speed of the head during the seek operation is referred to as Vrs, and a circumferential travel speed is referred to as Vts, the controller controls at least one of the radial travel speed of the head and number of revolutions of the magnetic disk to satisfy a relationship (Vr1/Vt1)<(Vrs/Vts).

Abstract: A request to access data programmed to a memory sub-system is received. A determination is made of whether memory cells of the memory sub-system that store the programmed data satisfy one or more cell degradation criteria. In response to a determination that the memory cells satisfy the one or more cell degradation criteria, an error correction operation to access the data is performed in accordance with the request.

Abstract: There is provided a recording medium, a recording apparatus, a recording method, a reproducing apparatus, and a reproduction method that make it possible to correctly reproduce multilevel codes recorded at high density. A multilevel code of at least three ML values produced by coding user data into a (d,k)-RLL code of the ML values and a particular pattern of the ML values that includes a run of repeated codes which is greater than a maximum run k of the multilevel code are recorded on a recording medium. In addition, reproduction is performed from the recording medium, and the multilevel code is decoded according to the particular pattern. For example, the present technology can be applied to a recording medium, a recording/reproducing apparatus that performs recording on and reproduction from the recording medium, and the like.

Abstract: According to one embodiment, first, a frequency to be corrected by an MA additional filter is specified based on a head position error spectrum and a multi-rate sensitivity characteristic, in a state before the MA additional filter is added. Then, a candidate in which a peak of the multi-rate sensitivity characteristic is equal to or less than a threshold value and a head position error is minimized is determined as the MA additional filter to be used, in a state in which each of a plurality of candidates of the MA additional filter is added.

Abstract: A magnetic tape cartridge includes a magnetic tape in which a plurality of servo patterns are recorded along a longitudinal direction, and a storage medium that is configured to store servo format information including servo pattern inclination information which is information on an inclination of the servo pattern with respect to a first imaginary straight line.

Abstract: A computer program product, system, and method are provided for direct resistance measurement of a magnetoresistive (MR) head of a storage drive in a storage system. In one embodiment, a voltage difference across the MR reader head is measured directly by applying an AC current to the MR head to generate an AC voltage across the MR head that can propagate through filter capacitors and be measured. In one embodiment, the voltage difference is amplified and the peak-to-peak voltage at the output of the amplifier is captured. Similarly, a reference voltage difference across a reference resistance is measured directly by applying a reference AC current to a reference resistance. The resistance of an MR reader head may be calculated directly as a function of the respective voltage differences without including the resistance of any bias resistors biasing the MR head.

Abstract: An industrial integrated development environment (IDE) allows project topologies to be defined using an industrial domain-specific language (DSL) script. DSL scripting language can be used to define a control system topology in terms of the devices that make up the control system as well as the data connections between those devices. The IDE system can translate resulting topology to a project tree that serves as the basis for a control system project.

Abstract: According to one embodiment, a magnetic disk device comprises a disk, a first head, a second head, a controller. The disk includes a first surface and a second surface different from the first surface. The first head carries out read and write of data from and to the first surface. The second head carries out read and write of data from and to the second surface. The controller adjusts a spiral speed of at least one of the first head and the second head according to a cylinder offset amount corresponding to a positional difference between the first head and the second head. The spiral speed is a speed at which spiral servo patterns are to be written.

Abstract: A method of determining radial position of a magnetic head that includes a first read sensor and a second read sensor includes: with the first read sensor, detecting a servo spiral formed on a disk; with the second read sensor, detecting the servo spiral; measuring a time interval between when the servo spiral is detected by the first read sensor and when the servo spiral is detected by the second read sensor; and based on the time interval, determining a radial position of the magnetic head relative to the disk.

Abstract: In accordance with an embodiment, a hard disk drive includes voice coil motors (VCMs) coupled to respective control units configured to drive retract an operation of the VCMs in the hard disk drive. The retract operation of the VCMs includes a sequence of retract steps. The control units are allotted respective time slots for communication over a communication line with the respective time slots synchronized via the common clock line, and are configured to drive sequences of retract steps of the VCMs in the hard disk drive in a timed relationship.

Abstract: A method for starting hard disks, applied in an electronic device, the method includes: starting a storage in the electronic device, and the storage comprising hard disks and a backplane extension chip; sending preset request signals by the hard disks to the backplane extension chip; verifying a number of the hard disks by the backplane expansion chip according to the request signals; when the number of the hard disks is verified successfully, performing type verification on the hard disks by the backplane expansion chip; and sending a start signal by the backplane expansion chip to the target hard disks having a successful type verification according to a preset start sequence and a preset number of the hard disks, to start the target hard disks.

Abstract: The present disclosure is generally related to a tape drive comprising a tape head and a controller coupled to the tape head. The tape head comprises one or more modules, each module comprising a plurality of write heads aligned in a first row, a plurality of read heads aligned in a second row parallel to the first row, and at least four first servo heads aligned in the second row. Two or more first servo heads of the at least four first servo heads are configured to concurrently read first servo data from a first servo track. The controller is configured to concurrently process the first servo data, to compute the position of the tape head based on a known spacing between the at least two servo heads, and to dynamically adjust a position of the tape head based on the processed first servo data.

Abstract: A tape drive (226) for use in a tape library (10) that retains at least one tape cartridge (220) that retains magnetic tape (250) includes a drive housing (226A) and a media conditioner (255). The drive housing (226A) is configured to receive the tape cartridge (220). The media conditioner (255) is coupled to the drive housing (226A). The media conditioner (255) is configured to condition the magnetic tape (250) when the tape cartridge (220) is received within the drive housing (226A). The media conditioner (255) can be configured to remove at least one of abrasives, contaminants and lubricants that are on the magnetic tape (250) when the tape cartridge (220) is received within the drive housing (226A). The magnetic tape (250) is configured to move along a predefined path (251) within the drive housing (226A), which is defined by one or more rollers (254).

Abstract: The present disclosure generally relates to a tape drive including a tape head. The tape head comprises two modules, where each module comprises 64 writers, 64 readers, and three pairs of servo readers aligned with the 64 readers in a first row. The three pairs of servo readers comprise a first pair disposed at a first end of the first row, a second pair disposed between two groups of 32 readers, and a third pair disposed at a second end of the first row. The writers are disposed in a second row parallel to the first row, and are each aligned with an adjacent reader. The spacing between each reader and each writer is about 150 ?m to about 200 ?m. Each module is configured to write data to a tape using the 64 writers and to read verify the newly written data using the 64 readers.

Abstract: A controller provides a plurality of first sections with numerical information on a first scale. The plurality of first sections are obtained by dividing a recording surface of a magnetic disk in units of first memory areas in each of which a first volume of data can be written by an SMR method. The first scale corresponds to a sequence of the first sections. The controller provides a plurality of second sections with numerical information on a second scale. The plurality of second sections are obtained by dividing the recording surface of the magnetic disk in units of second memory areas in each of which the first volume of data can be written by a CMR method. The second scale corresponds to a sequence of the second sections. The controller executes a plurality of commands in order based on a numerical information on the first scale or the second scale.

Abstract: According to one embodiment, a magnetic disk device comprising a magnetic disk, a magnetic head, and a controller that registers an address and a positioning error, determines whether or not a positioning error of a second sector that is two tracks ahead in a radial direction of a first sector to which a data is written is registered, and when the positioning error of the second sector is registered, sets a first threshold that allows a write operation for a positioning error of the first sector based on the positioning error of the second sector, and determines whether or not the positioning error of the first sector exceeds the first threshold, and stops the write operation when the positioning error of the first sector exceeds the first threshold.

Abstract: Various illustrative aspects are directed to a data storage device comprising a slider with a resistive temperature detector (RTD) having a first resistance electrically connected to a first amplifier and a plurality of controlled current sources and switches, and one or more processing devices configured to: control the switches to generate an alternating-bias signal having a first clock frequency for biasing the first resistance, modulate an input signal of the first amplifier using the first clock frequency to generate a modulated signal, demodulate an amplified modulated signal at an output of a second amplifier using the first clock frequency to generate a resistance detection signal, the second amplifier coupled to the first amplifier, and process the resistance detection signal to determine the first resistance and/or a change in value of the first resistance.

Abstract: According to one embodiment, a magnetic disk device comprises a disk, a head that writes data to the disk and reads data from the disk, and a controller that controls a position of the head so as to write a first spiral servo pattern to the disk, and overwrite a second spiral servo pattern different from the first spiral servo pattern by shifting in a radial direction of the disk from the first spiral servo pattern.

Abstract: Various illustrative aspects are directed to a data storage device comprising a disk; a read/write head having read and write portions configured to read data from and write data to the disk; read and write heaters configured to thermally adjust read and write spacings of the read and write portions from the disk surface; and a controller configured to control power applied to the read and write heaters based on a dual heater power ratio (DHR) of the respective power applied to each heater. The DHR is set based on a point during touchdown at which a reader shield and a writer shield have maximum contact with the surface of the disk (DHRmax).

Abstract: Various illustrative aspects are directed to a data storage device, comprising: one or more disks; an actuating mechanism comprising one or more heads, and configured to position the one or more heads proximate to disk surfaces of the one or more disks; and one or more processing devices. The one or more processing devices are configured to: determine a first burst value based on an averaged value of a first set of one or more bursts; determine a second burst value based on an averaged value of a second set of one or more bursts; generate a position error signal (PES) based on the determined first burst value and the determined second burst value; and control a position of at least one head among the one or more heads based on the PES.

Abstract: The present disclosure generally relates to a tape drive including a tape head. The tape head comprises one or more modules, each module comprising a plurality of writers disposed in a first row, a plurality of readers disposed in a second row parallel to the first row, a first servo reader aligned with either the first row or the second row, and a second servo reader aligned in a third row parallel to the first and second rows. The first servo reader and the second servo reader are offset from one another in a first direction and in a second direction perpendicular to the first direction, the first direction being a cross-track direction. The first servo reader and the second servo reader are spaced apart in the first direction about 1 ?m to about 20 ?m.

Abstract: Systems, apparatuses, methods, and computer program products are disclosed for facilitating contactless and socially distant payments. Specifically, certain embodiments are configured for generating and utilizing a user expression map for associating user expressions to control events. The methods further correspond to receiving, in real-time, image data representative of at least a portion of a user body, the user body tracked by a contactless human to device interface system. The methods further include causing a retrieval of a user expression map from a first computing device for provision to a second computing device, determining using the user expression map, that the image data is associated with a control event indicative of a directive to perform a particular transaction, and triggering the control event to cause performance of the particular transaction based, at least in part on the determination that the image data is associated with the control event.