Patents Examined by Brian Butcher
  • Patent number: 8842507
    Abstract: A thermally-assisted magnetic recording (HAMR) disk drive uses a thermal sensor to accurately monitor laser power during writing. The disk drive controller, or a separate processor, computes a prediction of the laser power from a history of laser power settings. This predicted value is compared with the measured value from the thermal sensor. If the difference is too large or too small, indicating that the laser power is too high or too low, an error signal is sent to the disk drive controller. The disk drive controller may adjust the laser power setting and initiate a re-write of the data. The predicted laser power is calculated from a convolution of a sequence of current and prior laser power settings with a sequence of coefficients. A calibration process generates the sequence of coefficients when the disk drive is idle or just after it is powered on.
    Type: Grant
    Filed: October 22, 2013
    Date of Patent: September 23, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Toshiki Hirano, Lidu Huang, Tetsuo Semba, Barry Cushing Stipe
  • Patent number: 8837071
    Abstract: An apparatus includes a near-field transducer at or near an air bearing surface of the apparatus. A write pole is disposed at or near the air bearing surface and proximate the near-field transducer, respectively. A thermal sensor is disposed at the air bearing surface and within a protrusion region of the air bearing surface defined relative to at least one of the near-field transducer and the write pole. The thermal sensor is configured to produce a signal indicative of a temperature at the protrusion region.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: September 16, 2014
    Assignee: Seagate Technology LLC
    Inventors: Declan Macken, James Dillon Kiely, Manuel Charles Anaya-Dufresne
  • Patent number: 8830614
    Abstract: Approaches for a hard-disk drive (HDD) having a balanced resistive temperature detector (RTD). A HDD includes a head slider comprising a single RTD. A read/write IC comprises a balance resistor having the same resistance as the single RTD when the head slider is not in physical contact with the disk. The same amount of current flows through the single RTD and the balance resistor except when the head slider is in physical contact with the disk. Detecting a voltage change across the single RTD enables physical contact between the head slider and the disk to be accurately detected using a circuit with low noise. Alternately, the head slider may include two RTDs connected in sequence, and the balance resistor may possess the same resistance as the two RTDs. The two RTDs may vary inversely with environmental changes to avoid the need to recalibrate the balance resistor after any environmental change.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: September 9, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Samir Y. Garzon, Rehan Ahmed Zakai, John Thomas Contreras
  • Patent number: 8824076
    Abstract: The present invention is related to systems and methods for adaptive parameter modification in a data processing system.
    Type: Grant
    Filed: August 28, 2012
    Date of Patent: September 2, 2014
    Assignee: LSI Corporation
    Inventors: Lu Pan, Seongwook Jeong, Haitao Xia
  • Patent number: 8824085
    Abstract: A heat-assisted magnetic recording system may include, but is not limited to: at least one magnetic recording read/write head; at least one laser diode configured to illuminate at least a portion of at least one magnetic recording medium; at least one laser power level sensor configured to detect a power level of the at least one laser diode; and a controller configured to modify one or more power level settings associated with the at least one laser diode in response to one or more output signals of the at least one laser power level sensor.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: September 2, 2014
    Assignee: LSI Corporation
    Inventors: Ross S. Wilson, Jason P. Brenden, Toan V. Tran
  • Patent number: 8817406
    Abstract: A magnetic-recording head with touch-down detector incorporating a carbon nano-tube (CNT). The magnetic-recording head includes a write element, a read element and a touch-down detector. The write element is configured to write data to a magnetic-recording disk. The read element is configured to read data from the magnetic-recording disk. The touch-down detector includes a thermal sensor, and a CNT portion. The thermal sensor is configured to convert heat to a voltage signal. The CNT portion is configured to touch down on the magnetic-recording disk. The CNT portion is also coupled to the thermal sensor, and is configured to transfer heat generated by contact between the CNT portion and the magnetic-recording disk to the thermal sensor. A hard-disk drive (HDD) including the magnetic-recording head with touch-down detector incorporating a CNT, and a method for detecting contact between the magnetic-recording head and a recording surface of a magnetic-recording disk are also provided.
    Type: Grant
    Filed: December 30, 2011
    Date of Patent: August 26, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Patent number: 8817407
    Abstract: An apparatus that includes a write pole, the write pole including a magnetic material; a near field transducer-heat sink (NFT-HS), the NFT-HS including a noble metal; and a power source configured to electrically bias the write pole with respect to a second structure.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: August 26, 2014
    Assignee: Seagate Technology LLC
    Inventors: James G. Wessel, Steven C. Riemer, Zoran Jandric
  • Patent number: 8817403
    Abstract: According to one embodiment, a magnetic disk drive includes a disk and a controller. The disk includes a plurality of zones each having a plurality of tracks. The disk is formatted such that a plurality of servo frames are discretely recorded in each of the plurality of tracks. The plurality of servo frames include servo preamble data of a second length which corresponds to the zone having the track and which is less than or equal to a first length serving as a reference. The controller allows a head to read the servo frames from the disk via a read amplifier.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: August 26, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takumi Sato
  • Patent number: 8810946
    Abstract: A microwave-assisted magnetic recording system configured to perform magnetic recording with high density, including a high-frequency magnetic field generation element whose width is narrower than a track width of a main pole. A magnetic field vector from the main pole is perpendicularly incident on a film surface of the high-frequency magnetic field generating unit, by a shield material arranged to have a high magnetic permeability so that the main pole magnetic field is corrected and induced, and a hard bias layer to which a desired static magnetic field is added. Areas having high magnetic field gradients overlap each other by performing an offset of the high-frequency magnetic field generating unit of the magnetic head from the central line of the main pole.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: August 19, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Kan Yasui, Harukazu Miyamoto, Masukazu Igarashi
  • Patent number: 8804265
    Abstract: Calibrating a frequency filter includes applying a series of input electrical signals at different frequencies to a shock sensor, using circuitry to identify a particular one of the frequencies as a resonance frequency of the shock sensor based on responses of the shock sensor to the series of input signals, and setting a center frequency of the notch filter equal to the particular frequency identified as the resonance frequency of the shock sensor.
    Type: Grant
    Filed: December 23, 2011
    Date of Patent: August 12, 2014
    Assignee: Rohm Co., Ltd.
    Inventors: Yoshito Otaguro, Shinichi Miura
  • Patent number: 8773803
    Abstract: Three structures, and processes for manufacturing them, that improve the performance of a TAMR feature in a magnetic write head are disclosed. This improvement is achieved by making the separation between the edge plasmon generator and the plasmon shield less than the separation between the edge plasmon generator and the optical wave-guide.
    Type: Grant
    Filed: October 18, 2012
    Date of Patent: July 8, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Xuhui Jin, Hiroyuki Ito, Shigeki Tanemura, Dayu Zhou
  • Patent number: 8760786
    Abstract: A tape edge sensor system for detecting lateral movement of a storage tape includes a first photo-emitter, a first photo-detector positioned to receive a first light signal from the first photo-emitter, a first aperture disposed between the first photo-emitter and the first photo-detector, and a feedback system connected to the first photo-emitter and the first photo-detector. The first aperture defines a first region at a first tape edge through which the first light signal is received by the first photo-detector with the storage tape blocking a portion of the first light signal. The feedback system determines the first photo-detector's signal amplitude and adjusts the first light signal such that the first photo-detector signal amplitude is within a first average amplitude range. A tape edge sensor system using compensating photo-interrupters is also provided.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: June 24, 2014
    Assignee: Oracle International Corporation
    Inventors: Faramarz Mahnad, Scott D. Wilson
  • Patent number: 8755138
    Abstract: Various embodiments of the present inventions provide systems and methods for adaptive servo address mark detection.
    Type: Grant
    Filed: February 22, 2013
    Date of Patent: June 17, 2014
    Assignee: LSI Corporation
    Inventors: Dahua Qin, Haitao Xia, Xun Zhang
  • Patent number: 8743494
    Abstract: An extended servo mark word is used when an error is detected from a servo mark. For example, a servo mark associated with a disk drive track may be detected during a data access operation. In response to an error in detecting the servo mark, at least one adjacent bit is evaluated together with the servo address mark to overcome the error.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: June 3, 2014
    Assignee: Seagate Technology LLC
    Inventors: Mustafa Can Ozturk, Puskal Prassad Pokharel, Barmeshwar Vikramaditya
  • Patent number: 8736999
    Abstract: Aspects of the disclosure provide a circuit. The circuit includes a biasing circuit and an amplifier. The biasing circuit is configured to generate a bias voltage and a bias current based on a first resistor having a first resistance determined based on a second resistor. The amplifier is biased based on the bias voltage and bias current to generate an electrical signal that varies in response to a resistance change of the second resistor.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: May 27, 2014
    Assignee: Marvell International Ltd.
    Inventor: Thart Fah Voo
  • Patent number: 8736993
    Abstract: Approaches are provided for a hard-disk drive (HDD) and techniques for using multiple LUNs per HDD where each LUN is mapped to a head/disk interface. In one example, a HDD generates multiple LUNs and assigns each to a single head, such that data written by a first head is only associated to a first LUN, and so forth.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: May 27, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Zvonimir Z. Bandic, Cyril Guyot
  • Patent number: 8730613
    Abstract: An apparatus and associated methodology for retracting a first member in relation to a second member. The first member may be selectively moveable by a first motor and the second member may be selectively moveable by a second motor that operably generates a back electromagnetic force (BEMF) voltage VBEMF. In an embodiment a retract control circuit may control movement of the first member via the first motor in response to a loss of supply power to the second motor. An embodiment of the apparatus may include a backup power source storing a voltage VB after the loss of supply power. Another embodiment of the apparatus may include retract logic operative on the retract control circuit to divide the VB from the VBEMF to energize the first motor by the VBEMF and not the VB when the VB is greater than a predetermined threshold voltage and a loss of the supply power to the second motor is detected.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: May 20, 2014
    Assignee: Seagate Technology LLC
    Inventors: Shuang Quan Min, June Christian Ang, Tze Ming Jimmy Pang, Kian Keongh Ooi, Paul E. Dienstbier
  • Patent number: 8711504
    Abstract: Disk drives are described in which the conventional write-to-read gap is omitted in selected sectors which frees up space that can be used for other purposes including writing a higher number of bits in the user data area in the gapless selected sectors. Alternative embodiments can use the additional space for servo information such as a repeatable run out (RRO) field. Conventional servo sector SID formats can be used for both gapped and gapless SIDs, which means that during seeking and reading operations full SIDs can be read for every wedge. The tradeoff for being able to write data much closer to the gapless SIDs is that the servo system does not detect the SAM or read the TID in the gapless SIDs during write operations.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: April 29, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Timothy John Everett, James Bowling French, Jr., Gary Allan Herbst, Anthony Edwin Welter
  • Patent number: 8705198
    Abstract: An implementation of a system disclosed herein provides a method of compensating for a change in write position of a recording head due to a change in an operating condition of the recording head.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: April 22, 2014
    Assignee: Seagate Technology LLC
    Inventors: Ravi Hebbar, Peter Stuart Harllee, III
  • Patent number: 8698779
    Abstract: A touch panel comprises a substrate and a transparent conductive layer including a plurality of groups of first conductive patterns, second conductive patterns, and third conductive patterns, and a plurality of first wires, second wires, and third wires. Each group of first conductive patterns is arranged along a first direction. Each group of second conductive patterns is arranged along a second direction and located at a first side of the second direction. Each group of third conductive patterns is arranged along the second direction and located at a second side of the second direction. Each group of first conductive patterns, each group of second conductive patterns, and each group of third conductive patterns are electrically insulated to each other. Each second conductive pattern among each group of second conductive patterns has different areas, and each third conductive pattern among each group of third conductive patterns has different areas.
    Type: Grant
    Filed: November 7, 2012
    Date of Patent: April 15, 2014
    Assignee: HTC Corporation
    Inventor: Shu-Hung Tseng