Patents by Inventor Albert John Wallash

Albert John Wallash has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9786331
    Abstract: The present disclosure generally relates to a shielded three-layer patterned ground structure in a PCB. The PCB may be disposed in a hard disk drive. To reduce costs, PCBs are being made with only four total layers separated by dielectric material. Conductive traces in PCBs can have the problem of common mode current flowing through the traces and thus increasing the magnitude of EMI noise. By providing a shielded three-layer patterned ground structure, not only is the cost reduced, but so is the common mode current and the magnitude of EMI noise, all without any negative impact to the differential signal.
    Type: Grant
    Filed: July 26, 2016
    Date of Patent: October 10, 2017
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventor: Albert John Wallash
  • Patent number: 9717140
    Abstract: The present disclosure generally relates to a shielded patterned ground structure in a PCB. The PCB may be disposed in a hard disk drive. Conductive traces in PCBs can have the problem of common mode current flowing through the traces and thus increasing the magnitude of EMI noise. By providing a shielded patterned ground structure, the common mode current is reduced as is the magnitude of EMI noise, yet there is no negative impact to the differential signal.
    Type: Grant
    Filed: October 29, 2015
    Date of Patent: July 25, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventors: John T. Contreras, Junjia Liu, Satoshi Nakamura, Jack Nguyen, Albert John Wallash
  • Publication number: 20170127509
    Abstract: The present disclosure generally relates to a shielded patterned ground structure in a PCB. The PCB may be disposed in a hard disk drive. Conductive traces in PCBs can have the problem of common mode current flowing through the traces and thus increasing the magnitude of EMI noise. By providing a shielded patterned ground structure, the common mode current is reduced as is the magnitude of EMI noise, yet there is no negative impact to the differential signal.
    Type: Application
    Filed: October 29, 2015
    Publication date: May 4, 2017
    Inventors: John T. CONTRERAS, Junjia LIU, Satoshi NAKAMURA, Jack NGUYEN, Albert John WALLASH
  • Patent number: 9196266
    Abstract: An interconnect between the read/write circuitry and the read/write head in a magnetic recording hard disk drive (HDD) for two-dimensional magnetic recording (TDMR) has the read sensor signal lines located on a lower level of a bi-level structure of conductive lines. Common return lines are located on an upper level above the signal lines and on the lower level between the signal lines. All of the return lines on the upper level are connected to one another by cross-connect lines, and vias are located along the interconnect and connect the upper return lines with the lower return lines and with the ground plane of the interconnect's electrically conductive substrate. The interconnect is a coaxial-like interconnect because the return lines are located around each signal line and thus shield each signal line from the other signal lines, much like the outer conductive shield of a coaxial cable.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: November 24, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: John Contreras, Albert John Wallash, Rehan Ahmed Zakai
  • Patent number: 9117474
    Abstract: A method, apparatus, and system are provided for implementing a write head device for writer-to-disk contact detection and spacing sensing of recording heads in hard disk drives (HDDs). A write head device, such as a spin-torque oscillator (STO), is provided between a main pole tip and a surrounding magnetic shield of the writer in the recording head. A pair of connections is provided to the magnetic shield and the main pole of the writer, and resistance of the write head device is measured to detect writer to disk spacing and contact.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: August 25, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: John Contreras, Samir Y. Garzon, Timothy Scott Hughbanks, Albert John Wallash
  • Patent number: 9117469
    Abstract: A “split-substrate” design is described for the metal ground layer in the suspension for a slider for use in a disk drive that reduces crosstalk from signals being transmitted on the conductive traces and allows externally induced interference to be shunted away from sensitive traces along selected portions of the suspension. In embodiments of the invention a slit formed in the metal ground layer to provide two parallel ground paths respectively on the left and right sides of the selected portion of the suspension. By positioning interference signal generating traces like writer traces on one side of the slit, that side becomes the noisy ground path leaving the other side as a “quiet” ground path. The shape, positioning and grounding of the split substrate structure can shunt return/ground currents created by external RFI into the noisy leg and thereby shield the quiet leg.
    Type: Grant
    Filed: December 1, 2014
    Date of Patent: August 25, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: John Contreras, Albert John Wallash, Rehan Ahmed Zakai
  • Patent number: 8873231
    Abstract: An electronic device enclosure configured to shield against electromagnetic interference (EMI). The electronic device enclosure includes an electronic device-enclosure base and at least one laterally disposed blunt boss. The electronic device-enclosure base includes a bottom, and sides and attached to the bottom in a boxlike configuration. The laterally disposed blunt boss is configured so as to be disposed between, and to couple electrically, a side of the electronic device-enclosure base and a vertical flange of an electronic device-enclosure cover. The electronic device-enclosure base and the electronic device-enclosure cover are configurable with respect to said laterally disposed blunt boss to shield an interior space enclosed by the electronic device-enclosure base and the electronic device-enclosure cover against EMI at a resonant frequency of a slot of the electronic device enclosure.
    Type: Grant
    Filed: December 23, 2010
    Date of Patent: October 28, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Ravinder Singh Ajmani, Ryan Thomas Davis, Antony Nguyen, Albert John Wallash
  • Patent number: 8570684
    Abstract: A method, apparatus, and system for implementing spin integrated spin-torque oscillator (STO) with an interface bias control for hard disk drives. Bias circuitry for a spin-torque oscillator (STO) is integrated with a slider for microwave assisted magnetic recording (MAMR). The slider includes read and write transducers and the integrated STO bias circuitry controls a bias potential applied to a write return pole to the write transducer with respect to a disk.
    Type: Grant
    Filed: October 5, 2012
    Date of Patent: October 29, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: John Thomas Contreras, Ikuya Tagawa, Albert John Wallash
  • Publication number: 20120162895
    Abstract: An electronic device enclosure configured to shield against electromagnetic interference (EMI). The electronic device enclosure includes an electronic device-enclosure base and at least one laterally disposed blunt boss. The electronic device-enclosure base includes a bottom, and sides and attached to the bottom in a boxlike configuration. The laterally disposed blunt boss is configured so as to be disposed between, and to couple electrically, a side of the electronic device-enclosure base and a vertical flange of an electronic device-enclosure cover. The electronic device-enclosure base and the electronic device-enclosure cover are configurable with respect to said laterally disposed blunt boss to shield an interior space enclosed by the electronic device-enclosure base and the electronic device-enclosure cover against EMI at a resonant frequency of a slot of the electronic device enclosure.
    Type: Application
    Filed: December 23, 2010
    Publication date: June 28, 2012
    Inventors: Ravinder Singh Ajmani, Ryan Thomas Davis, Antony Nguyen, Albert John Wallash
  • Patent number: 8004795
    Abstract: Methods and structures for the fabrication of a thin film, longitudinal and perpendicular recording heads are disclosed. The heads comprise a plurality of embedded static dissipative layers that extend a few nanometers from the air bearing surface. These extended layers are first to contact the magnetic media surface and drain any electric charge buildup before a damaging discharge occurs with read or write head components. The embedded static dissipative layers are particularly useful for use in heads utilizing thermal fly height control systems, which tend to increase the probability of damaging electrical discharge through critical head components.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: August 23, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Albert John Wallash, Hong Zhu
  • Patent number: 7957083
    Abstract: A method for detecting an impending failure of a disk drive system. The method includes monitoring a signal from a magnetoresistive sensor for the presence of a negative signal spike. A negative signal spike can indicate that the carbon overcoat of the magnetic medium has been locally worn off. The resulting localized absence of carbon overcoat causes the magnetoresistive sensor to short to the magnetic medium. This causes a short, abrupt drop in voltage, which can be used as evidence of the localized absence of the carbon overcoat. If such a negative signal spike is detected, the user can be notified of an impending system failure. In addition to, or in lieu of, notifying the user of the impending system failure, the system can be automatically de-activated to prevent data loss and/or further damage to the recording system.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: June 7, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Albert John Wallash, Hong Zhu
  • Publication number: 20090168262
    Abstract: Methods and structures for the fabrication of a thin film, longitudinal and perpendicular recording heads are disclosed. The heads comprise a plurality of embedded static dissipative layers that extend a few nanometers from the air bearing surface. These extended layers are first to contact the magnetic media surface and drain any electric charge buildup before a damaging discharge occurs with read or write head components. The embedded static dissipative layers are particularly useful for use in heads utilizing thermal fly height control systems, which tend to increase the probability of damaging electrical discharge through critical head components.
    Type: Application
    Filed: December 26, 2007
    Publication date: July 2, 2009
    Inventors: Albert John Wallash, Hong Zhu
  • Publication number: 20090029188
    Abstract: A method for detecting an impending failure of a disk drive system. The method includes monitoring a signal from a magnetoresistive sensor for the presence of a negative signal spike. A negative signal spike can indicate that the carbon overcoat of the magnetic medium has been locally worn off. The resulting localized absence of carbon overcoat causes the magnetoresistive sensor to short to the magnetic medium. This causes a short, abrupt drop in voltage, which can be used as evidence of the localized absence of the carbon overcoat. If such a negative signal spike is detected, the user can be notified of an impending system failure. In addition to, or in lieu of, notifying the user of the impending system failure, the system can be automatically de-activated to prevent data loss and/or further damage to the recording system.
    Type: Application
    Filed: July 23, 2007
    Publication date: January 29, 2009
    Inventors: Albert John Wallash, Hong Zhu
  • Publication number: 20040017640
    Abstract: A magneto-resistive read head having a “parasitic shield” provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.
    Type: Application
    Filed: February 2, 2001
    Publication date: January 29, 2004
    Inventors: Timothy Scott Hughbanks, Neil Leslie Robertson, Steven Howard Voldman, Albert John Wallash
  • Patent number: 6498696
    Abstract: A method, devices, and an article of manufacture for reducing magnetic instability in a magnetoresistive read head of a combined read-write head after writing data onto a magnetic storage medium. The last write pulse polarity that results in the least amount of magnetic instability in the read head is determined, and is referred to as the designated polarity. Then, after a set of write pulses is written, it is determined whether the last write pulse has the designated polarity. If the last write pulse does not have the designated polarity, then an additional write pulse with the designated polarity is written. Thus, the last write pulse before a read always has the designated polarity, thereby reducing the magnetic instability of the read head, and consequently improving read head performance.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: December 24, 2002
    Assignee: International Business Machines Corporation
    Inventors: Michael Paul Salo, Albert John Wallash
  • Patent number: 6359750
    Abstract: A magneto-resistive read head having a “parasitic shield” in a data storage system provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: March 19, 2002
    Assignee: International Business Machines Corporation
    Inventors: Timothy Scott Hughbanks, Neil Leslie Robertson, Steven Howard Voldman, Albert John Wallash
  • Patent number: 6320715
    Abstract: A method, devices, and an article of manufacture for reducing magnetic instability in a magnetoresistive read head of a combined read-write head after writing data onto a magnetic storage medium. The last write pulse polarity that results in the least amount of magnetic instability in the read head is determined, and is referred to as the designated polarity. Then, after a set of write pulses is written, it is determined whether the last write pulse has the designated polarity. If the last write pulse does not have the designated polarity, then an additional write pulse with the designated polarity is written. Thus, the last write pulse before a read always has the designated polarity, thereby reducing the magnetic instability of the read head, and consequently improving read head performance.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: November 20, 2001
    Assignee: International Business Machines Corporation
    Inventors: Michael Paul Salo, Albert John Wallash
  • Patent number: 6288880
    Abstract: A magneto-resistive read head having a “parasitic shield” provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: September 11, 2001
    Assignee: International Business Machines Corporation
    Inventors: Timothy Scott Hughbanks, Neil Leslie Robertson, Steven Howard Voldman, Albert John Wallash
  • Patent number: 6169639
    Abstract: A method, devices, and an article of manufacture for reducing magnetic instability in a magnetoresistive read head of a combined read-write head after writing data onto a magnetic storage medium. The last write pulse polarity that results in the least amount of magnetic instability in the read head is determined, and is referred to as the designated polarity. Then, after a set of write pulses is written, it is determined whether the last write pulse has the designated polarity. If the last write pulse does not have the designated polarity, then an additional write pulse with the designated polarity is written. Thus, the last write pulse before a read always has the designated polarity, thereby reducing the magnetic instability of the read head, and consequently improving read head performance.
    Type: Grant
    Filed: October 23, 1998
    Date of Patent: January 2, 2001
    Assignee: International Business Machines Corporation
    Inventors: Michael Paul Salo, Albert John Wallash
  • Patent number: 6081409
    Abstract: A magneto-resistive read head having a "parasitic shield" provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: June 27, 2000
    Assignee: International Business Machines Corporation
    Inventors: Timothy Scott Hughbanks, Neil Leslie Robertson, Steven Howard Voldman, Albert John Wallash