Abstract: A transceiver includes a first common T-coil circuit coupled to a first input-output pin of the transceiver, a termination impedance coupled to the first common T-coil circuit and configured to match an impedance of a transmission line coupled to the first common T-coil circuit, an amplifier configured to receive an input signal from the first input-output pin through the first common T-coil circuit based on a receive enable signal, and a first transmission buffer configured to transmit an output signal to the first input-output pin through the first common T-coil circuit based on a transmit enable signal.

Abstract: A data storage device includes a stack of data storage disks mounted on a spindle, a first arm and a second arm. The stack comprises a first plurality of upper disks and second plurality of lower disks. The first arm is movably attached to an actuator shaft, the first arm having a first head end that supports a first head, the first arm configured to move along a first portion of the actuator shaft to enable the first head to interact with data storage surfaces of the first plurality of upper disks. The second arm has a second head end that supports a second head, the second arm attached to and configured to move along a second portion of the actuator shaft, independently of the first arm, to enable the second head to interact with data storage surfaces of the second plurality of lower disks.

Abstract: A storage device includes a controller that determines a degree of data degradation for a data track targeted by a pending read command and sets a head/media clearance parameter for execution of the read command based on the determined degree of data degradation for the data track, the head/media clearance parameter providing for a greater head-media separation when the determined level of degradation is lower than when the determined level of degradation is higher.

Abstract: A storage device includes a controller that determines a degree of data degradation for a data track targeted by a pending read command and sets a head/media clearance parameter for execution of the read command based on the determined degree of data degradation for the data track, the head/media clearance parameter providing for a greater head-media separation when the determined level of degradation is lower than when the determined level of degradation is higher.

Abstract: The technology disclosed herein pertains to a system and method for managing off-track retry. An implementation of a method of determining offset direction for read off-track retry includes storing analog to digital converter (ADC) values of data read from a data sector by a data reader in a read channel buffer, calculating an indicator value of the distribution of the ADC values, determining an amount of offset for the data reader based on the indicator value, and moving the data reader by the amount of offset before performing a read retry operation.

Abstract: A method includes receiving a write command including data to be stored and a logical block address associated with the data. The method includes selecting, from a pre-defined plurality of cooling zones of a data storage chassis, a cooling zone in which to store the data. The method further includes writing the data to a data storage device in the cooling zone.

Abstract: An exemplary data storage device includes an actuator arm assembly, a top guide rail, a bottom guide rail, and a first ball bearing. The actuator arm assembly includes a first post defining a pivot axis that is inclined between about 5 degrees and about 25 degrees from a horizontal plane defined by a data storage disk surface. The top guide rail includes a first rolling surface that is parallel to the pivot axis. The bottom guide rail is spaced from the top guide rail and includes a second rolling surface that is parallel to the first rolling surface. The first ball bearing includes a first inner race and a first outer race, the first inner race surrounding the first post, and the first outer race in contact with the first rolling surface or the second rolling surface. An exemplary method of assembling a data storage device is also described.

Abstract: A data storage device includes a base, a data storage disk, an actuator arm, a suspension, and a piezoelectric actuator. The data storage disk is attached to the base and has a read/write surface defining an x-y plane. The actuator arm is attached to the base at a first pivot point to rotate parallel to the x-y plane. The suspension is attached to the actuator arm at a second pivot point, the suspension having a first end comprising a curved edge surface, and a second end supporting a head that is configured to interact with the read/write surface. The piezoelectric actuator is disposed on the actuator arm and comprises a biasing finger configured to contact the curved edge surface to rotate the suspension parallel to the x-y plane about the second pivot point. An actuator arm assembly and a method of use are also described.

Abstract: An apparatus comprises a write pole for writing data to a magnetic recording medium and a near-field transducer (NFT) optically coupled to a laser source and configured to produce a thermal spot on the medium. A laser driver applies laser operation power (Iop) to the laser source. A channel circuit generates symbols having a length of nT, where T is a channel clock rate and n is an integer. The laser driver applies Iop to the laser source and a write driver applies bi-directional write currents to the write pole to record the symbols at a location of the thermal spot on the medium, wherein a duration of applying Iop to the laser source by the laser driver is dependent on a length of the symbols and the effective thermal spot size.

Abstract: The technology disclosed herein pertains to a method for determining expected command completion time (CCT), the method including receiving a plurality of position error signals (PESs) for an HDD over a predetermined time period, determining sigma of the plurality of PESs, retrieving upper off-track limits (UOL) for one or more data sectors of the HDD, calculating average number of retrieved sectors (A) between two consecutive occurrences of the |PES|>UOL for the HDD, and determining required number of revolutions (CCT) to collect data based on the average number of retrieved data sectors (A) and a total number of requested data sectors (N).

Abstract: A data storage device includes a stack of data storage disks mounted on a spindle, a first arm and a second arm. The stack comprises a first plurality of upper disks and second plurality of lower disks. The first arm is movably attached to an actuator shaft, the first arm having a first head end that supports a first head, the first arm configured to move along a first portion of the actuator shaft to enable the first head to interact with data storage surfaces of the first plurality of upper disks. The second arm has a second head end that supports a second head, the second arm attached to and configured to move along a second portion of the actuator shaft, independently of the first arm, to enable the second head to interact with data storage surfaces of the second plurality of lower disks.

Abstract: A data storage device includes a ferromagnetic center pole, a drive coil for an actuator arm assembly, and a magnetic assembly surrounding the drive coil. The drive coil surrounds the center pole and has a top, a bottom, and first and second sides; the first side is attached to the actuator arm assembly. The magnetic assembly includes a top magnet disposed above and spaced from the center pole, a bottom magnet disposed below and spaced from the center pole, and a side magnet disposed proximate the second side of the coil and spaced from the center pole. In another embodiment, a linear actuator comprises a ferromagnetic center pole, a drive coil supported for linear motion on a rail, and a magnetic assembly. A method including linearly moving a drive coil along a center pole by a magnetic field is also described.

Abstract: The technology disclosed herein provides a system for generating a personal unclonable function (PUF) for a user based on a biometric data related to the user. Implementations of the system include a camera to generate a partial image of a user's tongue, a sensor to generate a moisture level in the user's saliva, a PUF generator configured to generate a PUF benchmark of the user based on combination of the partial image of a user's tongue and the moisture level in the user's saliva, and an access control unit configured to control access to one or more user devices based on the PUF benchmark.

Abstract: A hard disk drive includes a base deck, a motor coupled to the base deck, a magnetic recording medium coupled to the motor and having a first zone and a second zone, and a controller. The controller is programmed to cause the motor to rotate at either a first speed or a second speed when data is to be read from the first zone and to cause the motor to rotate at the first speed when data is to be written to the first zone and the second zone.

Abstract: The technology disclosed herein provides a system for allowing users to login into one or more devices without a password. Implementations of the system include one or more biometric data collection devices (shoe, glasses, watch) and a device configured to store one or more user identification data, receive a request for user verification, request user's biometric data from one or more of the biometric data collection devices, generate a personal unclonable function (PUF) value based on combination of at least one of the user identification data and the user's biometric data, and verify the user's identity by comparing the PUF value to the user's PUF benchmark.

Abstract: A torsional mode damping controller in which the controller modifies electrical power to an electrical motor to provide active damping control of torsional vibration in rotating masses. The controller receives a measurement of a rotational speed of the rotating masses ?m and an estimate or a measurement of a torque transmitted between the rotating masses Tsh; based on the received transmitted torque Tsh, generate a compensating torque to suppress vibration Tcom; based on the received rotational speed ?m and the compensating torque Tcom, generate an electromagnetic torque modification signal Tmodi; and modify the electrical power provided to the electrical motor on the basis of the electromagnetic torque modification signal Tmodi. The controller is further configured to generate compensating torque Tcom by applying a filter to the received transmitted torque Tsh, based on plural tunable parameters including a tuning gain K, a cut-off frequency ?n and a resonant damping ratio ?.

Abstract: A receiver includes a first T-coil circuit at an input of the receiver and configured to receive an input signal, a termination impedance coupled to the first T-coil circuit and configured to match an impedance of a transmission line coupled to the first T-coil circuit, and an amplifier including a first input and a second input and configured to amplify a differential signal at the first and second inputs, a calibration switch coupled to the amplifier and configured to selectively electrically connect or disconnect the first and second inputs of the amplifier, and a first receive switch configured to selectively electrically connect or disconnect a center node of the first T-coil circuit and the amplifier.

Abstract: The technology disclosed herein pertains to a system and method for storing data on a storage media using both down-track super parity and cross-track super parity. Specifically, a method disclosed herein provides for generating down-track super parity values for data on the plurality of tracks and storing the down-track super parity values on a down-track super parity row of the storage block and generating cross-track super parity values for data on the plurality of rows and storing the cross-track super parity values on a cross-track upper parity track, wherein the cross-track super parity value for any given row is generated by inputting the data on the given row into an exclusive-OR (XOR) gate.

Abstract: Electrical power systems and methods of controlling electrical power systems are described. One such electrical power system comprises: a first ac bus and a first generator set configured to supply the first ac bus with ac electrical power; a second ac bus and a second generator set, configured to supply the second ac bus with ac electrical power; an interconnecting transformer connected between the first and second ac busses; a primary electrical load connected to both the first and second ac busses via a converter arrangement; an auxiliary load connected to the first ac bus; and a controller configured to control the first generator set according to a first droop control profile and to control the second generator set according to a second droop control profile, the first and second droop control profiles relating respective generator operating frequencies of the first and second generator sets to respective output powers of the first and second generator sets.