Patent classifications
G11B20/10481
Magnetic recording and reproducing apparatus and magnetic recording and reproducing method
A magnetic recording and reproducing apparatus for recording and reproducing bit information comprising a magnetic head having a spin torque oscillator configured to readout bit information which is recorded on a magnetic recording medium, a detector configured to detect amplitude of a first signal, the first signal which is to reproduce the bit information, and a controller configured to control the magnetic head so as to read the bit information recorded on the magnetic recording medium when the amplitude of the first signal detected by the detector is smaller than a predetermined value.
MAGNETIC RECORDING AND REPRODUCING DEVICE AND METHOD OF CONTROLLING MAGNETIC RECORDING AND REPRODUCING DEVICE
According to one embodiment, a magnetic recording and reproducing device which has a magnetic recording medium, a magnetic head, and a recording current output unit. Magnetic data is recorded on the magnetic recording medium. The magnetic head records the magnetic data on the magnetic recording medium. The recording current output unit supplies a recording current to the magnetic head so as to magnetize the magnetic head. A waveform of the recording current has a first slope for a first period to record data of first information continuously and a second slope for a following second period to switch the data to data of second information and to record the data of the second information. The first slope and the second slope are different from each other.
Dynamic write field test for a perpendicular recording head
A method of testing a dynamic write field of a recording head includes preparing a test magnetic medium and recording a write signal on the test magnetic medium with the write signal being set at a first write parameter and a second write parameter. An average of multiple read-back signals of the recorded write signal are captured to determine an average amplitude of the read-back signals. The recording of the write signal on the test magnetic medium and the capturing of the average of multiple read-back signals of the recorded write signal are repeated to determine the average amplitude of the read-back signals by fixing the first write parameter of the write signal and changing the second write parameter of the write signal until the average amplitude of the read-back signals saturates.
Selecting a maximum laser power for a calibration based on a previously measured function
An operational laser power for a heat-assisted, magnetic recording head is selected based on a function of a write quality metric versus laser power. The write quality metric of data written to a magnetic recording medium is monitored at the operational laser power. Responsive to the write quality metric satisfying a threshold, a power difference between the operational laser power and an offset laser power is determined. The offset laser power corresponds to a point of the function where the write quality metric is approximately equal to the threshold. A maximum laser power is set for a calibration operation. The maximum laser power is based on the sum of the operational laser power and the power difference.
Adjusting track width to compensate for offset writing of a track
An offset from track center of a writer that is writing to a track of a magnetic recording medium is determined. A write current applied to a write coil of the writer is adjusted to compensate for the offset. The adjusting of the write current affects a width of the track.
Optical storage system divider based draw verification with digitally synthesized writing laser pulse signal
An optical storage system includes an optical head configured to split a light beam into a higher power main beam and a lower power side beam. The system also includes a controller. The controller is configured to modulate the higher power main beam according to writing commands to write to an optical medium while processing first data resulting from the lower power side beam being reflected from the medium and second data obtained from a look-up table that maps the writing commands to digital representations of filtered writing strategy waveforms to remove noise from the first data caused by the higher power main beam and generate output indicative of written data directly after writing.
MANAGING FAR AND NEAR TRACK ERASURE BY DYNAMIC CONTROL OF A WRITE CURRENT PARAMETER OF A MAGNETIC DISK DRIVE
A method may include causing a write head of a magnetic data storage drive to write a first portion of data to a magnetic data storage device of the magnetic data storage drive based at least in part on a first value of at least one parameter of a write current. The method may include updating a value of a write counter and determining whether the value of the write counter is greater than or equal to a threshold write count. The method may also include adjusting the at least one parameter of the write current to a second, different value. The method may further include causing the write head to write a second portion of data to the magnetic data storage device based at least in part on the second value of the at least one parameter of the write current.
Heat-assisted magnetic recording device capable of laser calibration during a background operation
A storage device performs a background operation involving seeking a read/write head between inner and outer diameters of a disk of the storage device. During the seeking, adjacent test tracks are written at a diameter between the inner and outer diameters of the disk. The adjacent test tracks are written using varying levels of laser power applied to the disk via the read/write head. An optimum value of the laser power is determined based on reading at least one of the adjacent test tracks.
Data storage device with power loss adaptation
A data storage device can employ a transducing head that accesses data stored on a data storage medium as directed by a controller. In response to experiencing a power disruption, the controller can predict at least one performance metric lost due to the power disruption and subsequently compensate for the power disruption by assuming the at least one predicted performance metric is correct.
SYSTEMS AND METHODS FOR TIME SHIFTING TASKS
Systems, apparatuses, and methods for time shifting tasks in a computing system. A system may include a display control unit configured to process pixels for display. The display control unit may include at least one or more pixel processing pipelines, a control unit, and a pixel buffer. The control unit may be configured to monitor the amount of data in the pixel buffer and set the priority of pixel fetch requests according to the amount of data in the pixel buffer. If the control unit determines that an inter frame period will occur within a given period of time, the control unit may prevent the priority of pixel fetch requests from being escalated if the amount of data in the pixel buffer falls below a threshold. The control unit may also be configured to fill the buffers of the display control unit with as much data as possible during the inter frame period.