Patents Assigned to XTAL Technologies, Ltd.
  • Patent number: 5594354
    Abstract: The present invention discloses a method for obtaining frequency parameters to determine the resonator frequencies, the synchronous peak separation frequency, and the normal center frequency of a coupled-dual resonator crystal. Under this method, a plurality of frequencies are applied to a first electrode. This application is performed once while the second electrode and the common electrode are connected by a short circuit, and then again when the second electrode and the common electrode are capacitively connected or open circuited. During each application of the plurality of frequencies to the crystal, the phase response for the output of the resonator circuit is monitored. Then the time response of the crystal is determined. Next, the time delay relative maxima for the time response is determined. Finally, the frequencies at which the time delay relative maxima occur are determined.
    Type: Grant
    Filed: January 9, 1995
    Date of Patent: January 14, 1997
    Assignee: Xtal Technologies, Ltd.
    Inventors: Gerald E. Roberts, Michael E. Roberts
  • Patent number: 5587663
    Abstract: The present invention discloses a method for obtaining frequency parameters to determine the resonator inductances of a crystal. Under this method, a plurality of frequencies are applied to a first electrode. This application is performed once while the second electrode and the common electrode are connected by a short circuit, and then again when the second electrode and the common electrode are capactively connected or open circuited. During each application of the plurality of frequencies to the crystal, the phase response for the output of the resonator circuit is monitored. Then the time response of the crystal is determined. Next, the time delay relative maxima for the time response is determined. Finally, the frequencies at which the time delay relative maxima occur are determined. These frequencies correspond to the inflection points where the change in phase goes from monotonically increasing to monotonically decreasing.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: December 24, 1996
    Assignee: XTAL Technologies, Ltd.
    Inventors: Gerald E. Roberts, Michael E. Roberts