Abstract: A magnetic disk device includes a plurality of magnetic disks, a plurality of sliders each including one or more resistive elements, each of which is arranged to face a recording surface of one of the plurality of magnetic disks, and is provided corresponding to the plurality of magnetic disks, and a processor configured to detect a change in a resistance value of one or more of the plurality resistive elements.

Abstract: A data storage device configured to access a magnetic tape is disclosed comprising a plurality of data tracks. A first head is configured to access a first data track comprising a first sync mark, and a second head is configured to access a second data track comprising a second sync mark. The first head is used to read first data from the first data track, wherein the first data comprises a plurality of symbols, and the second head is used to read the second sync mark from the second data track. The first data is symbol synchronized based on the second head reading the second sync mark from the second data track.

Abstract: According to one embodiment, a magnetic disk apparatus includes a magnetic disk, a magnetic head, and a controller. The magnetic disk includes a plurality of tracks. The magnetic head performs read/write from/to the plurality of tracks. The controller controls, in a first case in which, during execution of write to a first track among the plurality of tracks, a position of the magnetic head is displaced from a target position corresponding to the first track toward a second track, and a first distance exceeds a first threshold, write to the second track under a condition different from a condition in a second case in which the first distance is less than the first threshold. The second track is a track different from the first track among the plurality of tracks. The first distance is the distance between the target position and the position of the magnetic head.

Abstract: A data storage device is disclosed comprising a voice coil motor (VCM) configured to actuate a head over a disk. The data storage device further comprises control circuitry comprising a digital current control loop including a windowed delta-sigma analog-to-digital converter (ADC) configured to control the VCM. A vibration of the data storage device is measured, and at least one of a gain or a window of the windowed delta-sigma ADC is configured based on the measured vibration.

Abstract: According to one embodiment, a magnetic disk device includes a disk including two first servo sectors and at least a second servo sector, a head, and a controller, wherein the first servo sector includes burst data and a first data pattern written before the circumferential direction of the burst data, the second servo sector includes the burst data, the first data pattern, and a second data pattern written after the circumferential direction of the burst data, a first frequency of the first data pattern is different from a second frequency of the second data pattern, and a first length of the first data pattern is different from a second length of the second data pattern.

Abstract: According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

Abstract: Devices and techniques for temperature informed memory refresh are described herein. A temperature counter can be updated in response to a memory device write performed under an extreme temperature. Here, the write is performed on a memory device element in the memory device. The memory device element can be sorted above other memory device elements in the memory device based on the temperature counter. Once sorted to the top of these memory device elements, a refresh can be performed the memory device element.

Abstract: According to one embodiment, a magnetic disk device includes a disk including a first sector arranged at a first radial position deviated from a target position in a radial direction by a first offset amount larger than a first threshold value, a head that writes data to the disk and reads data from the disk, and a controller that reads the first sector by arranging the head at a second radial position deviated from the target position by a second offset amount different from the first offset amount.

Abstract: A data storage device (DSD) includes a base-deck, a disc above the base-deck, and a shaft extending perpendicular from the base-deck. The DSD also includes a head stack assembly (HSA) including a head gimbal assembly having a load beam and a head at a first end of the HSA. The head interacts with a surface of the disc. The HSA also includes a second end movably mounted on the shaft. The DSD additionally includes an elevator that linearly moves the HSA along the shaft to adjust a distance between the load beam and the surface of the disc in response to receiving a feedback signal associated with the interaction of the head with the surface of the disc. The feedback signal is one of a plurality of feedback signals employed by the elevator to adjust the distance between the load beam and the surface of the disc.

Abstract: A data storage device is disclosed comprising a first plurality of heads actuated over a first subset of disk surfaces by a first actuator, and a second plurality of heads actuated over a second subset of disk surfaces by a second actuator. A plurality of access commands is received, wherein each access command is associated with one of the heads. A scalar is configured for each access command based on at least one of a current radial location of the corresponding head or a target radial location of the corresponding head associated with executing the access command. The access commands are sorted based on the scalars, and one of the access commands is selected for execution based on the sort.

Abstract: A data processing method including: searching for a smallest data unit of a buffer with regard to appending data in an append write request; sequentially writing at least some of the appending data into the smallest data unit of the buffer to obtain a first smallest data unit to be stored, and writing data not yet written in the appending data into at least one smallest data unit to obtain at least one second smallest data unit to be stored; writing the first smallest data unit to be stored into a storage device in an overwriting manner, and sequentially writing the at least one second smallest data unit to be stored into the storage device; and buffering a smallest data unit not fully written that corresponds to the appending data. The present disclosure ensures data integrity, increase operation convenience, and write operation efficiency.

Abstract: Systems and methods are disclosed for resource allocation for multi-actuator systems. In some examples, a data storage device can include two or more independently moveable voice coil motor (VCM) actuators where the resources of the system to operate the VCM actuators are divided. The disclosure here describes methods to allocate or re-allocate the divided resources, such as unused resources, to a VCM actuator that has a need for more resources. The methods and systems herein can also be applied to other actuator systems.

Abstract: Systems and methods are disclosed for calibrating actuators in a multi-stage servo system. In certain embodiments, a method may comprise performing a calibration process on a multi-stage actuated servo system, including simultaneously injecting voltage injections into multiple microactuators of the servo system, measuring a resulting position error signal (PES), and determining gain settings for each of the multiple microactuators based on the PES. Multiple microactuators can therefore be calibrated during a single-injection calibration operation.

Abstract: The present disclosure generally relates to magnetoresistive device apparatus and methods. The magnetoresistive device includes a read head. The read head is a tunneling magnetoresistive reader that includes a multilayer free layer structure. The multilayer structure includes one or more layers of Co or FCC FeCo sandwiched between a BCC CoFe50 nanolayer and an amorphous CoFeB layer. The one or more layers of Co or FCC FeCo create nanocrystalline disorder that allows the thickness of the amorphous CoFeB layer to be reduced while retaining or even improving TMR and reducing the interlayer coupling field.

Abstract: According to one embodiment, a magnetic disk device includes a disk having a first area, and a second area to which data is temporary written, a head including a write head which writes data to the disk, and an assisting element which generates energy which improves write performance of the write head, and a controller which writes data to the first area by supplying energy having a first value to the assisting element, and writes data to the second area by supplying energy having a second value different from the first value to the assisting element.

Abstract: Described are magnetic recording heads that include a read transducer and a write transducer, with the two transducers being arranged in a side-by-side configuration.

Abstract: A method for mitigating intentional potential interruptions in data signal communication, the method comprising transmitting (S21) or receiving (S23) a data signal, determining when a portion of the data signal has been successfully transmitted (S22) or received (S24), when the portion of the data signal has been successfully transmitted or received, generating (S25) a transmission interruption signal, and in response to the transmission interruption signal, performing one or more maintenance operations, such as beamforming, that may potentially interrupt transmission or reception of the data signal.

Abstract: A servo writer includes a writing head that writes a servo signal on a long magnetic tape that is traveling and at least two first guide rollers that guide the travel of the magnetic tape, in which the at least two first guide rollers on which a spiral groove is provided have a circumferential surface that has contact with the traveling magnetic tape, tensile forces act on the magnetic tape from the at least two first guide rollers in a width direction of the traveling magnetic tape, and the tensile forces that act on the magnetic tape from the at least two first guide rollers cancel each other.

Abstract: A method, and associated computer program product and mobile computing device, for backing-up information stored in the mobile computing device. The mobile computing device detects one or more support computing devices located within a corresponding communication range and being available to support the mobile computing device for backing-up the information stored in the mobile computing device. The mobile computing device detects a dangerous condition indicative of a risk of inoperability of the mobile computing device. The mobile computing device sends back-up information corresponding to selected information stored in the mobile computing device to at least one of the support computing devices in response to the detection of the dangerous condition to cause the at least one support computing device to upload the back-up information to a back-up computing system.

Abstract: The present invention provides a method for positioning short circuit failure, used to position the short circuit point between a first metal wire and a second metal wire. The positioning method comprises: measuring the resistance between the first metal wire and the second metal wire, and positioning the first region where the short circuit point is located by a resistance ratio. In the first region, the short circuit point may be gradually approached by periodically cutting the first metal wire and the second metal wire, electrically isolating the cut portions, and performing a plurality of voltage contrast analysis on the first metal wire and the second metal wire based on the principle of the dichotomy, thereby accurately locating the short circuit point. With the positioning method provided by the present invention, the region where the short circuit defect of the nA (nano ampere) level is located may be accurately found from the first metal wire and the second metal wire that are extremely long.

Abstract: A data storage device is disclosed comprising a head actuated over a magnetic media. A write boost is configured to a first setting, and a first pattern of magnetic transitions is written to a first servo field of a servo sector on the magnetic media using the first setting for the write boost. The write boost is configured to a second setting different from the first setting, and the first pattern of magnetic transitions is written to a second servo field of the servo sector on the magnetic media using the second setting for the write boost.

Abstract: A computer-implemented method includes, by one or more processors in electronic communication with a tunneling magnetoresistive sensor, wherein the tunneling magnetoresistive sensor is a component of a magnetic storage drive configured to read magnetic data from a magnetic storage medium, detecting a short across the tunneling magnetoresistive sensor, measuring a change in resistance of the tunneling magnetoresistive sensor, measuring a change in voltage amplitude for the tunneling magnetoresistive sensor, and dividing said change in voltage amplitude by said change in resistance to yield a ratio. The computer-implemented method further includes, responsive to the ratio being greater than a predetermined ratio threshold, determining that the short is caused by a magnetic shunt. A corresponding computer program product and computer system are also disclosed.

Abstract: A memory system according to an embodiment includes a nonvolatile memory and a memory controller. The memory controller converts a received value read from the nonvolatile memory into first likelihood information by using a first conversion table, executes decoding on the first likelihood information and outputting a posterior value, outputs an estimated value of the received value obtained on the basis of the posterior value in a case where the decoding is successful. The memory controller generates a second conversion table on the basis of the posterior value in a case where the decoding fails. The memory controller converts the received value into second likelihood information by using the second conversion table in a case where the second conversion table has been generated, and executes decoding on the second likelihood information and outputs a posterior value.

Abstract: According to one embodiment, a servo write method includes a head and a disk having a plurality of spiral servo patterns which are written radially in a first direction from a first area to a second area other than the first area at velocity that varies between the first area and the second area, the method including moving the head in a second direction opposite to the first direction to read each of the spiral servo patterns, measuring a plurality of time intervals at which each of the spiral servo patterns is read in the first area, and writing a plurality of servo patterns to the first area based on the time intervals.

Abstract: According to one embodiment, a magnetic disk device includes a disk including a recording region including a servo sector, a head configured to write data to the disk and read data from the disk, and a controller configured to acquire a plurality of correction data for a repeatable runout of the recording region, the correction data respectively corresponding to a plurality of measurement positions set based on a first linearity error acquired by reading the servo sector, and to correct a position of the head based on the correction data.

Abstract: According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head including a read head to read data from the magnetic disk and a write head to write data to the magnetic disk, and a controller configured to control read/write from/to the magnetic disk by the magnetic head. The magnetic head includes a thermal actuator configured to project a head surface of the magnetic head to a recording surface of the magnetic disk, and a detector configured to detect a gap between the head surface and the recording surface of the magnetic disk. The controller controls a degree of projection of the magnetic head to the recording surface by the thermal actuator corresponding to the gap detected by the detector during the read/write.

Abstract: According to one embodiment, a method for evaluating a magnetic head is disclosed. The method can include measuring an electrical characteristic of a current path when an alternating-current magnetic field is applied to the magnetic head. The magnetic head includes the current path. The current path includes an oscillator. The method can include, based on the electrical characteristic, deriving a frequency value relating to an oscillation frequency of the oscillator.

Abstract: A power supply circuit comprises a power conversion circuit, a voltage selection circuit, and a voltage regulator. The voltage regulator coupled to the voltage selection circuit and a digital-to-analog converter (DAC), and the voltage regulator is configured to provide supply power to the DAC; the power conversion circuit is coupled to a first power supply and a power amplifier (PA), and the power conversion circuit is configured to convert, based on output power of the PA, a voltage of the first power supply into an output voltage that supply power to the PA; and the voltage selection circuit is coupled to a second power supply, the power conversion circuit and the voltage regulator, and the voltage selection circuit is configured to select the second power supply or the power conversion circuit to supply power to the voltage regulator based on an output voltage of the power conversion circuit.

Abstract: The present disclosure, in various aspects, describes technologies and techniques for use by a data storage device that includes a controller of a non-volatile memory (NVM). In one example, the controller applies a default storage format to a storage region of the NVM, the default storage format configuring the storage region as a number of distinct storage regions logically arranged along a horizontal dimension and a vertical dimension. The controller modifies the default storage format using a combination of horizontal dimension scaling and vertical dimension scaling based on a performance capability of the storage region to obtain a modified storage format. The controller applies the modified storage format to the storage region.

Abstract: A magnetic disk device includes a magnetic disk, a first read element, a second read element, and a controller. In the magnetic disk, first servo information is written. The controller controls the servo writing of second servo information on the magnetic disk, based on the first servo information. In addition, the controller controls acquisition of the first servo information by the first read element. The controller switches a read element to be used to control the servo writing from the first read element to the second read element based on quality of the first servo information acquired by the first read element.

Abstract: The present invention relates to platform power management.

Abstract: An automated test equipment (ATE) apparatus comprises a computer system comprising a system controller, wherein the system controller is communicatively coupled to a tester processor and an FPGA. The tester processor is operable to generate commands and data from instructions received from the system controller for coordinating testing of a device under test (DUT), wherein the DUT supports a plurality of non-standard sector sizes and a plurality of protection modes. The FPGA is communicatively coupled to the tester processor, wherein the FPGA comprises at least one hardware accelerator circuit operable to internally generate commands and data transparently from the tester processor for testing the DUT, and wherein the at least one hardware accelerator circuit is able to perform computations to calculate protection information associated with the plurality of protection modes and to generate repeatable test patterns sized to fit each of the plurality of non-standard sector sizes.

Abstract: A 3D printer is provided herein. In some embodiments, a 3D printer includes an ink tank for storing ink comprising a magnetic body, an injection nozzle which is linked to the ink tank and is adapted to inject ink, a substrate on which the injected ink is deposited, a heating unit so as to heat the ink coated onto the substrate by means of induction heating, and which is positioned behind the injection nozzle such that injection of ink occurs prior to induction heating of the ink; a carriage unit for changing the positions of the injection nozzle and the heating unit relative to the substrate: and a control unit for controlling the heating unit and the carriage unit.

Abstract: A storage system can include a first tape storage drive (TSD), a second TSD, and a printed circuit board assembly (PCBA) where the first and second TSD are coupled back-to-back, with the PCBA between the two. The first TSD can include a first enclosure, a first head assembly, a first actuator, and a first connector. The second TSD can include a second enclosure, a second head assembly, a second actuator, and a second connector. The PCBA can include a first side having a first mating connector configured to connect to the first connector for the first TSD, a second side opposite the first side, the second side having a second mating connector configured to connect to the second connector for the second TSD, and a controller configured to control activation of the first actuator of the first TSD and the second actuator of the second TSD.

Abstract: Provided is a servo controller that can prevent an unnecessary cut from being generated in a workpiece during oscillation machining. A servo controller 20 includes: an oscillation command generating unit 23 that generates an oscillation command for causing a workpiece W and a tool 11 to relatively oscillate; a position deviation estimating unit 31 that estimates an estimated position deviation from a moving command for causing the workpiece W and the tool 11 to relatively move; an adder that applies the oscillation command to a position deviation based on the moving command; a subtractor that deducts the estimated position deviation from a position deviation to which the oscillation command is applied; and a learning control unit that calculates a compensation amount from a position deviation based on the moving command after deducting the estimated position deviation.

Abstract: Implementation of a non-interfering micro-positioning device, for a tape drive write/read head module assembly utilizing piezoelectric elements, by generating at least two flexure brackets. The at least two flexure brackets may include the piezoelectric elements. Affixing at least one flexure bracket to a first side of the write/read head module assembly. Affixing at least one other flexure bracket to a second side of the write/read head module assembly.

Abstract: A system is provided to receive a first request to write data to an HDD which comprises a plurality of platters with corresponding heads, wherein a respective platter includes a plurality of tracks. The system aligns the heads at a same first position on a first track of each platter, and distributes the data as a plurality of data sectors to track sectors located at the same first position on the first track of each platter. The system then receives a second request to read the data from the HDD, and aligns the heads at a same random position on the first track of each platter. Subsequently, the system reads, during a single rotation of the platters, all data stored on the first track of each platter, stores the read data in a data buffer, and reshuffles the read data in the data buffer to obtain the requested data.

Abstract: Disclosed herein are circuits, architectures, and methods that provide for the control of a data storage device write head's trailing shield and main pole potential with respect to the disk using circuitry that is integrated with circuitry used to bias a spin torque oscillator (STO) apparatus. Various embodiments include slider connections with STO bias circuitry that resides in a read/write integrated circuit, which has a programmable circuit that generates a bias current with overshoot (bias kicks). Also disclosed are circuits that may be incorporated into a slider to mitigate radio-frequency interference.

Abstract: A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a fly height actuator (FHA) configured to adjust a fly height of the head over the disk. A temperature of the data storage device is measured, and the FHA is controlled as a function of the measured temperature. A first quality metric of the data storage device is measured, and when the first quality metric falls below a threshold, the FHA control as a function of the measured temperature is disabled and the FHA is controlled to decrease the fly height of the head.

Abstract: A method including obtaining a target actuation efficiency slope that is a linear function of temperature when a fixed active clearance is maintained between a transducing head and an adjacent storage surface in a sealed storage device. The target efficiency slope is obtained at least in part by a temperature dependence calibration of actuation efficiency. An operating temperature of the storage device is measure. Power to a clearance adjustment mechanism is adjusted to achieve the target actuation efficiency slope at the measured operating temperature.

Abstract: Magnetic sensors with effectively shaped side shields and their fabrication processes are provided. One such process includes depositing sensor materials on a substrate, shaping the sensor materials to form a stripe height of the magnetic sensor, shaping the sensor materials to form a track width of the magnetic sensor, depositing side shield materials on the shaped sensor materials, shaping the side shield materials such that a resulting side shield extends further than the stripe height, depositing an insulator layer on the shaped side shield materials, and shaping the insulator layer.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a recording head and a controller. The recording head includes a high-frequency oscillator disposed in a write gap between a main magnetic pole and a return magnetic pole and configured to oscillate in accordance with a bias voltage, and a bias voltage supply circuit configured to supply the bias voltage to the high-frequency oscillator. The controller includes a bias voltage controller configured to control the bias voltage to be applied to the high-frequency oscillator in accordance with a sampling frequency of data when the data is recorded on the magnetic disk by the recording head.

Abstract: A data storage device is disclosed comprising a head actuated over a disk surface, wherein the head comprises a plurality of elements including a write assist element. A bias signal applied to the write assist element is controlled such that the write assist element is substantially unprotruded, and while the write element is substantially unprotruded, an air bearing resonant frequency (ABRF) of the head and disk surface is measured. The bias signal applied to the write assist element is controlled such that the write assist element protrudes toward the disk surface, and while the write assist element protrudes toward the disk surface, the head is excited at the measured ABRF and the head touching down onto the disk surface is detected.

Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a trailing shield, a main pole, an STO disposed between the trailing shield and the main pole, and a non-magnetic conductive structure adjacent to the main pole and in contact with the STO. The STO includes an FGL and an SPL, and the FGL is disposed between the main pole and the SPL. The FGL includes a side extending over the main pole and at least a portion of the non-magnetic conductive structure. With the FGL disposed proximate to the main pole and over at least a portion of the non-magnetic conductive structure, current crowding and disturbance from the trailing shield are minimized.

Abstract: A switching circuit includes a switching circuit stage configured to supply a load via filter networks. Control circuitry is provided to control alternate switching sequences of transistors in the half-bridges of the switching circuit stage. A current flow line is provided between the output nodes of the half-bridges including an inductance between two switches. First and second capacitances are coupled with the output nodes of the half-bridges. The control circuitry switches first and second switches to the conductive state at intervals in the alternate switching sequences of the transistors in the half-bridges between switching the first pair of transistors to a non-conductive state and switching the second pair of transistors to a conductive state.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A magnetic disk device includes a case including a magnetic disk, a magnetic head configured to read or write data from or to the magnetic disk, an actuator configured to move the magnetic head, and a humidity sensor positioned within the case to measure a humidity in the case and output a measurement value; a control circuit configured to calculate a value of a voltage to be applied to the actuator based on a displacement amount of the magnetic head and the measurement value output from the sensor, and output the calculated value; and a servo controller configured to control the actuator by applying the voltage to the actuator according to the value output by the control circuit.

Abstract: A method includes processing, via an integrated circuit, data read from a first servo wedge; processing, via the integrated circuit, data from a second servo wedge; and skipping processing data from a third servo wedge positioned between the first servo wedge and the second servo wedge.

Abstract: According to one embodiment, a recording medium controller includes a recording medium, an input module, a reading module, and a writing module. The recording medium includes a write area and an escape area. The write area includes track groups. Each of the track groups is a unit for writing data and includes tracks. The input module receives a write command for data. The reading module reads data stored in the escape area and data from a first track group of the track groups. The writing module writes data received for the write command to the escape area, and writes merged data obtained by merging the data read from the escape area and the data read from the first track group to each track of a second track group of the track groups by using a shingle recording technique in which adjacent tracks are partly overlapped with each other.