Abstract: Write apparatus for a disk drive includes a write head, write current circuitry connected to the write head for generating a steady-state write current, overshoot current circuitry connected to the write head for generating write current overshoot pulses, and a T-coil termination network between (a) the write current circuitry and the overshoot current circuitry, and (b) a first node connected to a first input of a transmission line together with the write head. The T-coil termination network may include a first inductor connected to the first node, a second inductor coupled with the first inductor at a second node, and a first termination resistor between the first inductor and a common voltage. An output of the overshoot current circuitry may be connected to the first node, and an output of the write current circuitry may be connected to the second node.

Abstract: A Permanent Magnet Degausser Mechanism for Destroying the Functionality of Data Bearing Components of Magnetic Media Data Bearing Devices. This permanent magnet degausser mechanism provides reconciliation and tracking with a unique. identification tag using a secure and proprietary database, destruction of the functionality of the data bearing components of magnetic media data bearing devices using an automated movement system, a NSA Certified high strength degausser, digital pre-degaussing and post-degaussing readings to indicate the completion of the process of destroying the functionality of the data bearing components including storage of readings and containment of the remains of the magnetic media devices for verification.

Abstract: An ultrasonic device includes an ultrasonic transceiver that transmits an ultrasonic wave to a target at a predetermined interval, and that receives the ultrasonic wave reflected on the target so as to output a reception signal, a signal integration unit that outputs an integrated signal obtained by integrating the reception signals output within a predetermined period, and a position detection unit that detects a position of the target, based on a magnitude relationship between signal intensity of the integrated signal and a predetermined reference value.

Abstract: A data storage library system includes a data storage library having at least one library frame, at least one environmental conditioning unit associated with the data storage library and configured to control one or more interior environmental conditions within the at least one library frame, and at least one access door for providing access to an interior portion of the at least one library frame. The system also includes a library controller configured to initiate a service mode prior to and/or during a service procedure performed within the at least one library frame, wherein the service mode comprises configuring the at least one environmental conditioning unit to adjust the one or more environmental conditions within the at least one library frame toward one or more exterior environmental conditions outside of the data storage library. Optionally, a lock and/or indicator (visual and/or audible) may control access to the interior of the library frames.

Abstract: Provided are a computer program product, system, and method for indicating tracks as erased without deleting data for the tracks. In response to receiving erase commands to erase tracks in the storage, indicating the tracks as erased without performing an erase operation on the tracks subject to the erase command. Data in the storage for the tracks indicated as erased remains in the storage while requests are directed to the tracks indicated as erased. A command is received indicating an operation with respect to a target track. The operation to proceed is permitted with respect to the target track in response to determining that the target track is not indicated as erased. An alternate operation is performed providing a result different from the operation indicated in the command in response to determining that the target track is indicated as erased.

Abstract: A magnetic erasing device includes a rotating member provided in an internal space of a cylindrical housing, a first magnet and a second magnet attached to the rotating member, and a motor for driving the rotating member. The first magnet is arranged so that the S pole is exposed and the second magnet is attached so that the N pole is exposed. By rotating the rotating member, the magnetic field generated by the first and second magnets is changed.

Abstract: An I/O result receiving unit receives, from a storage device control unit, a result of I/O to a logical device with respect to an I/O request from an I/O control unit, a format target determining unit considers a failed track to be a format target when the failed track corresponds to a control area or an unallocated area, and a format requesting unit requests the storage device control unit to format a storage area of storage devices which corresponds to a page allocated to the failed track having been considered a format target.

Abstract: Provided are a computer program product, system, and method for indicating tracks as erased without deleting data for the tracks. In response to receiving erase commands to erase tracks in the storage, indicating the tracks as erased without performing an erase operation on the tracks subject to the erase command. Data in the storage for the tracks indicated as erased remains in the storage while requests are directed to the tracks indicated as erased. A command is received indicating an operation with respect to a target track. The operation to proceed is permitted with respect to the target track in response to determining that the target track is not indicated as erased. An alternate operation is performed providing a result different from the operation indicated in the command in response to determining that the target track is indicated as erased.

Abstract: An apparatus according to one embodiment includes a magnetic head having at least two tunneling magnetoresistance sensors, where a resistance of a tunnel barrier of each of the tunneling magnetoresistance sensors of the magnetic head is about 25 ohms or less, a drive mechanism for passing a magnetic medium over the magnetic head, and a controller electrically coupled to the magnetic head. In addition, the controller includes a biasing circuit, where the biasing circuit restricts a maximum voltage drop across the tunnel barrier.

Abstract: According to one embodiment, there is provided a disk device including a head, a disk, a first motor, and a first circuit. The disk has a recording surface. The first motor causes the head to seek along the recording surface. The first circuit can switch between a first state and a second state. The first state is a state where a current path of the first motor is electrically cut off from a first electricity storage unit. The second state is a state where the current path of the first motor is electrically connected to the first electricity storage unit.

Abstract: A data storage library system includes a data storage library having at least one library frame, at least one environmental conditioning unit associated with the data storage library and configured to control one or more interior environmental conditions within the at least one library frame, and at least one access door for providing access to an interior portion of the at least one library frame. The system also includes a library controller configured to initiate a service mode prior to and/or during a service procedure performed within the at least one library frame, wherein the service mode comprises configuring the at least one environmental conditioning unit to adjust the one or more environmental conditions within the at least one library frame toward one or more exterior environmental conditions outside of the data storage library. Optionally, a lock and/or indicator (visual and/or audible) may control access to the interior of the library frames.

Abstract: Certain aspects of the present disclosure provide a digital-to-analog converter (DAC). The DAC generally includes a plurality of transistors selectively coupled to an output of the DAC, and a biasing circuit coupled to gates of the plurality of transistors. The biasing circuit may include a first transistor having a gate coupled to a drain of the first transistor, a first buffer having an input coupled to the gate of the first transistor, a second transistor having a gate coupled to an output of the first buffer, a first resistive-capacitive (RC) circuit having a first resistive element and a first capacitive element, the first RC circuit being coupled between the gate of the first transistor and the gate of the second transistor, and a first switch coupled between the first resistive element and the first capacitive element.

Abstract: A data storage library system includes a data storage library having at least one library frame, at least one environmental conditioning unit associated with the data storage library and configured to control one or more interior environmental conditions within the at least one library frame, and at least one access door for providing access to an interior portion of the at least one library frame. The system also includes a library controller configured to initiate a service mode prior to and/or during a service procedure performed within the at least one library frame, wherein the service mode comprises configuring the at least one environmental conditioning unit to adjust the one or more environmental conditions within the at least one library frame toward one or more exterior environmental conditions outside of the data storage library. Optionally, a lock and/or indicator (visual and/or audible) may control access to the interior of the library frames.

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 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 method of operating a near-field communication (NFC) circuit, the method including: receiving an interference signal and a data signal through an antenna; adjusting magnitudes of the received interference signal and the received data signal; down-converting frequencies of the interference signal and the data signal, the magnitudes of which are adjusted; filtering the data signal by removing the frequency down-converted interference signal; and adjusting a magnitude of the filtered data signal. The adjusting of the magnitudes of the received interference signal and the received data signal may include adjusting the magnitudes of the interference signal and the data signal such that linearity of the data signal is maintained during signal processing performed on the interference signal and the data signal in the down-converting of the frequencies of the interference signal and the data signal, the filtering of the data signal, and the adjusting of the magnitude of the filtered data signal.

Abstract: A single magnetic pulse degaussing apparatus for use in erasing information contained on magnetic recording or storage media. A degaussing chamber for receipt of magnetic forces above 2.0 Tesla is accessible by upper and lower rotary actuated doors. The internal flux of a coil is measured by the current passing through the coil during the discharge cycle to provide a flux versus time measurements. The measurements are inserted into a performance verification algorithm to assure sufficient time for media destruction has taken place before releasing the media from the degaussing chamber.

Abstract: A method and system for cleaning and/or burnishing an article. The article is operated on by a burnishing object having one more cutting edges and one or more heating surfaces. The article rotates relative to the burnishing head and the cutting edges remove asperities from the article. The heating surface can be activated and can optionally protrude from the burnishing head to further reduce roughness of the surface of the article as the article is rotating relative to the head. The cutting edges and heating surfaces can be configured in shape and size (i.e., geometry) to accommodate the article.

Abstract: A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a first sensor element and a second sensor element. When configured into a first single-ended mode, a bias signal is applied to the first sensor element to generate a first single-ended output signal based on a response of the first sensor element, and when configured into a second single-ended mode, the bias signal is applied to the second sensor element to generate a second single-ended output signal based on a response of the first sensor element. When configured into a differential mode, the bias signal is concurrently applied to the first sensor element and the second sensor element to generate a differential output signal based on a response of the first sensor element and the second sensor element.

Abstract: The magnetic tape device includes: a magnetic tape; and a servo head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the servo head is a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes a servo pattern, and a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the magnetic layer is 48.0° to 53.0°.

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 sensor supported by a head transducer has a temperature coefficient of resistance (TCR) and a sensor resistance. The sensor operates at a temperature above ambient and is responsive to changes in sensor-medium spacing. Conductive contacts connected to the sensor have a contact resistance and a cross-sectional area adjacent to the sensor larger than that of the sensor, such that the contact resistance is small relative to the sensor resistance and negligibly contributes to a signal generated by the sensor. A multiplicity of head transducers each support a TCR sensor and a power source can supply bias power to each sensor of each head to maintain each sensor at a fixed temperature above an ambient temperature in the presence of heat transfer changes impacting the sensors. A TCR sensor of a head transducer can include a track-oriented TCR sensor wire for sensing one or both of asperities of the medium.

Abstract: In one general embodiment, an apparatus includes a plurality of read transducers arranged in an array, and a plurality of biasing circuits. Each biasing circuit is coupled to a unique one of the read transducers. Each biasing circuit is configured to selectively reverse a direction of a read current applied to the read transducer associated therewith.

Abstract: Methods and systems for monitoring contact joint integrity in an information handling system may include precisely monitoring a change in resistance of a resistive element associated with a contact joint. The change in resistance of the resistive element may be indicative of the integrity of the contact joint. The resistance may be measured using a modulated current source and by demodulating a voltage signal resulting from the modulated current flowing across the resistive element.

Abstract: A circuit is suggested comprising an electronic switching element, a logic unit coupled to control the electronic switching element, and a counter unit coupled to the logic unit, wherein the counter unit comprises a counter and an internal power supply.

Abstract: Embodiments of the present invention provide methods, systems, and computer program products for compensating for loss of current through shorted tunneling magnetoresistance (TMR) sensors. In one embodiment, for a magnetic head having multiple TMR read sensors, a first voltage limit is set for most parts and a second voltage limit is set for all of the parts. A number of TMR read sensors which are allowed to function between the first and the second voltage limits is determined using a probability algorithm, which determines the probability that the application of the second voltage limit will result in a dielectric breakdown within an expected lifetime of a drive is below a threshold value. For the number of TMR read sensors which are allowed to function at voltages between the first and second voltage limits, a determined subset of those sensors are then allowed to function at the second voltage limit.

Abstract: A receiver that is selectively reconfigurable in a first and a second selectable configuration is disclosed. Configured in the first selectable configuration, the receiver may provide a low impedance input. Configured in the first selectable configuration, a low common-mode input signal may be received. In an embodiment, configured in the first selectable configuration, signaling technologies, such as a Near Ground Signaling (NGS) may be received. Configured in the second selectable configuration, the receiver may provide a high impedance input. Configured in the second selectable configuration, a high common-mode input signal may be received. In an embodiment, configured in the second selectable configuration, signaling technologies, such as a Low Voltage Differential Signaling (LVDS), Pseudo Open Drain Logic (PODL) signaling, Differential Rambus Signaling Level (DRSL), and/or Series Stub Terminated Logic (SSTL) signaling may be received.

Abstract: A memory erasing method and a memory controller and a memory storage apparatus using the same are provided. The memory erasing method includes following steps. Physical blocks of a rewritable non-volatile memory module of the memory storage apparatus are logically grouped into at least a data area and a spare area. After the memory storage apparatus is powered on, an erase mark is configured for each of the physical blocks in the spare area, and each of the erase marks is initially set to an unerased state. After the memory storage apparatus enters a standby state, whether an erase command is executed on the physical blocks in the spare area is determined according to the erase marks. Thereby, the memory erasing method can effectively shorten the time for the memory storage apparatus to enter the standby state after the memory storage apparatus is powered on.

Abstract: A sensor supported by a head transducer has a temperature coefficient of resistance (TCR) and a sensor resistance. The sensor operates at a temperature above ambient and is responsive to changes in sensor-medium spacing. Conductive contacts connected to the sensor have a contact resistance and a cross-sectional area adjacent to the sensor larger than that of the sensor, such that the contact resistance is small relative to the sensor resistance and negligibly contributes to a signal generated by the sensor. A multiplicity of head transducers each support a TCR sensor and a power source can supply bias power to each sensor of each head to maintain each sensor at a fixed temperature above an ambient temperature in the presence of heat transfer changes impacting the sensors. A TCR sensor of a head transducer can include a track-oriented TCR sensor wire for sensing one or both of asperities of the medium.

Abstract: An apparatus for two-dimensional magnetic recording includes a storage medium, an array of magnetoresistive read heads disposed adjacent the storage medium and spaced to read a data track, a number of leads connected to the array of magnetoresistive read heads, and number of bias circuits connected to the array of read heads by the leads. The bias circuits can be configured to independently bias each of the array of read heads with the array of read heads connected in series or in parallel.

Abstract: Embodiments of the present invention provide methods, systems, and computer program products for compensating for loss of current through shorted tunneling magnetoresistance (TMR) sensors. In one embodiment, for a magnetic head having multiple TMR read sensors, a first voltage limit is set for most parts and a second voltage limit is set for all of the parts. A number of TMR read sensors which are allowed to function between the first and the second voltage limits is determined using a probability algorithm, which determines the probability that the application of the second voltage limit will result in a dielectric breakdown within an expected lifetime of a drive is below a threshold value. For the number of TMR read sensors which are allowed to function at voltages between the first and second voltage limits, a determined subset of those sensors are then allowed to function at the second voltage limit.

Abstract: The embodiments disclose an alternating current (AC) erase process configured to cancel out existing polarity of stack magnetic features on both sides of the stack and an AC reset process configured to initialize the polarity of the device stack magnetic features of both sides of a stack configured to create a uniform polarity.

Abstract: Systems and methods relating generally to sensing information, and more particularly to systems and methods for utilizing multiple readers to sense information.

Abstract: Systems and methods are provided for calibrating signals retrieved from a storage device using a first reader and a second reader. The systems and methods further include reading a first signal using the first reader and a second signal using the second reader. Control circuitry computes a calibration metric associated with the first reader and the second reader based on the combination of the first signal and the second signal. At least one of the first signal and the second signal is subsequently decoded based in part on the computed calibration metric.

Abstract: A data writing device may be constructed and operated with at least a data writer that has at least a write pole and a magnetic feature. A controller may selectively activate the magnetic feature to magnetically oscillate and produce a radio frequency signal proximal the write pole on an air bearing surface (ABS).

Abstract: A testing device tests a magnetic head with a read head structure including a read head element while applying an external magnetic field to the magnetic head. The testing device receives signals from the read head element and processes the signals to generate a spectral power density for the signals. The spectral power density is characterized for at least one frequency range. The characterization of the spectral power density is used to determine a characteristic of noise from the read head structure. The signals from the read head may be received with different applied magnetic fields and/or before or while thermally exciting the magnetic head. Additionally, a histogram of the signals may be generated and used to determine a second characteristic of the noise.

Abstract: An apparatus and associated method employing a bridge circuit having first and second microactuators attached to the apparatus. An excitation source is configured to independently drive each of the microactuators. A computation module is connected to the bridge circuit and is configured to independently measure an electrical output of each microactuator. The computation module uses the electrical outputs to characterize a bimodal modulation of the apparatus.

Abstract: A resistive sensor read-out apparatus is disclosed. In one embodiment, the resistive sensor read-out apparatus comprises an active sensor, a reference element, a bias circuit, a current-to-voltage converter, an analog-to-digital converter and a calibration processor. The bias circuit is coupled to the active sensor and the reference element and configured to calibrate one or more mismatches between the active sensor and the reference element. The current-to-voltage converter is coupled to an output of the bias circuit. The analog-to-digital converter is coupled to an output of the current-to-voltage converter. The calibration processor is coupled to an output of the analog-to-digital converter and configured to estimate an error caused by limited resolution mismatch calibration. The calibration processor is also configured to at least partially control calibration performed at the bias circuit based on the error.

Abstract: A magnetic sensor system includes a magnetic field generation unit for generating a target magnetic field and a magnetic sensor for detecting the target magnetic field, and is selectable between an operating state and a non-operating state. The magnetic sensor has a magnetic detection element including a magnetic layer whose magnetization direction varies according to the direction of the target magnetic field in a reference position. When in the operating state, the direction of the target magnetic field in the reference position varies when viewed from the magnetic sensor. When in the non-operating state, the direction of the target magnetic field in the reference position does not vary when viewed from the magnetic sensor and the magnetization direction of the magnetic layer is pinned in a first direction. The magnetic layer has an induced magnetic anisotropy that is imparted in advance to the magnetic layer.

Abstract: According to one embodiment, there is provided a magnetic disk device including a magnetic disk, a magnetic head, a heater, and a control unit. The magnetic head reads out information recorded on the magnetic disk. The heater is configured to adjust a magnetic spacing of the magnetic head from the magnetic disk. The control unit is configured to change a bias amount of the magnetic head according to setting of current flow through the heater.

Abstract: A receiver that is selectively reconfigurable in a first and a second selectable configuration is disclosed. Configured in the first selectable configuration, the receiver may provide a low impedance input. Configured in the first selectable configuration, a low common-mode input signal may be received. In an embodiment, configured in the first selectable configuration, signaling technologies, such as a Near Ground Signaling (NGS) may be received. Configured in the second selectable configuration, the receiver may provide a high impedance input. Configured in the second selectable configuration, a high common-mode input signal may be received. In an embodiment, configured in the second selectable configuration, signaling technologies, such as a Low Voltage Differential Signaling (LVDS), Pseudo Open Drain Logic (PODL) signaling, Differential Rambus Signaling Level (DRSL), and/or Series Stub Terminated Logic (SSTL) signaling may be received.

Abstract: The magnetic data eraser includes: a mounting and immobilizing tray on which a magnetic recording medium is mounted, the mounting tray being inclined at an angle of 60±10 degrees to the horizontal; a magnetizer that is encircled by a magnetizing coil, the magnetizer having a hollow portion into which the mounting and immobilizing tray is inserted; and a controller that causes an electric current to flow as an excitation current through the magnetizing coil, the excitation current generating a magnetic field that erases data stored in the magnetic recording medium.

Abstract: A bond pad set includes at least one ground pad and at least one electrical bond pad configured to bias and send/receive signals. The bond pad set is electrically connected to a multiplicity of electrical components. At least one electrical bond pad of the bond pad set is shared between two or more of the electrical components.

Abstract: Magnetoresistive (MR) bias is dynamically controlled in a tape drive using a processor device. Median tape head amplitude is monitored during a calibration operation, as measured across all tracks of the tape head, against predetermined thresholds of the tape drive for determining if the median tape head amplitude is below the threshold value. Upon determining the median tape head amplitude is below the threshold value during the calibration operation, a reference MR bias and a MR bias range is dynamically adjusted, during the calibration operation, for increasing the median tape head amplitude.

Abstract: A bias calibration circuit includes a first current source that can provide a majority biasing current, sufficient to provide most but not all of a desired bias voltage across a sensor. A second current source can provide a remaining amount of biasing current (minority biasing current) to provide a bias voltage across the sensor. In some embodiments, the current sources are programmable and codes are determined for programming the first and second current sources. The codes can be stored in a memory.

Abstract: Interface circuitry of a storage device or other type of processing device comprises a digital input detector and an adaptive power supply. The digital input detector comprises an input transistor. The adaptive power supply provides a variable supply voltage to the digital input detector that varies with a threshold voltage of the input transistor. In one embodiment, the variable supply voltage provided to the digital input detector by the adaptive power supply varies with the threshold voltage of the input transistor about a set point value determined as a function of an expected logic level of an input signal. For example, the set point value may be determined as a function of a minimum expected logic high input signal level. In such an arrangement, the input transistor is biased at or close to the threshold voltage for an input signal having the minimum expected logic high input signal level.

Abstract: A data storage device includes a recording medium including a data region for recording data and a nonvolatile recording unit distinct from the data region. In response to a request for executing erase processing with respect to the recording medium, first time information corresponding to initiation of the erase processing in the nonvolatile recording unit is stored, the erase processing after storing the first time information is executed, and second time information corresponding to completion of the erase processing is stored in the nonvolatile recording unit.

Abstract: An apparatus according to one embodiment includes a resistive link coupled to both an electrically conductive bus and an electrically conductive structure, the electrically conductive structure being positioned proximate to a media bearing surface. An apparatus according to another embodiment includes an array of transducers; an electrically conductive bus; and resistive links electrically coupled between the electrically conductive bus and at least one of: each of a plurality of electrically conductive structures, and at least some of the transducers.

Abstract: A method for detecting a contact event between a transducer and a recording medium is disclosed. The method includes positioning a transducer with respect to a recording medium, where the transducer includes a writer, a reader, a heater, and a thermally responsive sensor. The method further includes applying power to the heater to establish a fly height of the transducer; supplying a bias current through the thermally responsive sensor to generate a bias signal; measuring a root mean square (RMS) voltage VRMS of the thermally responsive sensor based on the bias signal; determining a threshold voltage VT; and detecting a contact event between the transducer and the medium based on VRMS being greater than VT.

Abstract: A disk drive is disclosed comprising a disk surface comprising a radius, a head operable to generate a read signal, and a voice coil motor (VCM) operable to actuate the head over the disk surface. A back electromotive force (BEMF) voltage generated by the VCM is measured. The VCM is controlled to move the head over substantially the entire radius of the disk surface in response to the BEMF voltage, and while moving the head the read signal from the head is processed to detect residual data recorded on the disk surface after erasing the disk surface.