Patents by Inventor Duane C. Phinney

Duane C. Phinney 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).

  • Wafer level test structure for detecting multiple domains and magnetic instability in a permanent magnet stabilized MR head
    Patent number: 5514953
    Abstract: A wafer level test structure and method detects multiple magnetic domains and magnetic domain instability in a test magnetic element. The apparatus comprises a first MR sensor designed to be held in a single magnetic domain by shape anisotropy and a second MR sensor having a permanent magnet to hold the element in a single magnetic domain. A circuit connects the first and second MR sensors to detect differences between the changes in resistance between the first and second sensors in the presence of a magnetic field or differences in resistance after the application and release of a magnetic field. The circuit is preferably a balance circuit in which imbalance in the presence of a magnetic field indicates the presence of multiple magnetic domains in at least one of the test sensors.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: May 7, 1996
    Assignee: Seagate Technology, Inc.
    Inventors: Allan E. Schultz, Peter K. George, William P. Wood, Duane C. Phinney, Patrick J. Ryan