Patents by Inventor Titkwan Hui

Titkwan Hui 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: 6476682
    Abstract: A temperature compensated crystal oscillation circuit adapted to be contained within a small device package and providing an output frequency accuracy of approximately +/−2 ppm over a temperature range or less than 2 minutes per year over the temperature range. The device includes crystal and a single integrated circuit wherein the integrated circuit has a temperature sensing circuit with a digital output, control circuitry, a memory circuit and a switched capacitor array for compensating the oscillation of the crystal oscillator over temperature.
    Type: Grant
    Filed: October 22, 1999
    Date of Patent: November 5, 2002
    Assignee: Dallas Semiconductor Corporation
    Inventors: Douglas Gene Cole, Ranganath Bagade, Titkwan Hui
  • Patent number: 6414559
    Abstract: A temperature compensated crystal oscillation circuit adapted to be contained within a small device package and providing an output frequency accuracy of approximately +/−2 ppm over a temperature range or less than 2 minutes per year over the temperature range. The device includes crystal and a single integrated circuit wherein the integrated circuit has a temperature sensing circuit with a digital output, control circuitry, a memory circuit and a switched capacitor array for compensating the oscillation of the crystal oscillator over temperature.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: July 2, 2002
    Assignee: Dallas Semiconductor Corporation
    Inventors: Douglas Gene Cole, Ranganath Bagade, Titkwan Hui
  • Patent number: 6160458
    Abstract: A temperature compensated crystal oscillation circuit adapted to be contained within a small device package and providing an output frequency accuracy of approximately +/-2 ppm over a temperature range or less than 2 minutes per year over the temperature range. The device includes crystal and a single integrated circuit wherein the integrated circuit has a temperature sensing circuit with a digital output, control circuitry, a memory circuit and a switched capacitor array for compensating the oscillation of the crystal oscillator over temperature.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: December 12, 2000
    Assignee: Dallas Semiconductor Corporation
    Inventors: Douglas Gene Cole, Ranganath Bagade, Titkwan Hui
  • Patent number: 5994970
    Abstract: A temperature compensated crystal oscillation circuit adapted to be contained within a small device package and providing an output frequency accuracy of approximately +/-2 ppm over a temperature range or less than 2 minutes per year over the temperature range. The device includes a crystal and a single integrated circuit wherein the integrated circuit has a temperature sensing circuit with a digital output, control circuitry, a memory circuit and a switched capacitor array for compensating the oscillation of the crystal oscillator over temperature.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: November 30, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Douglas Gene Cole, Ranganath Bagade, Titkwan Hui
  • Patent number: 5933039
    Abstract: Digital signal delay lines with electrically programmable and trimmable delay times, including electrically erasable and reprogrammable delay times. Floating gate field effect transistors are programmed to select current, capacitance, and/or threshold and thereby set a delay time determined by acurrent charging of a capacitor up to a threshold voltage. Trimming after packaging avoids package offsets. Temperature and power supply voltage compensation by current combining gives compensation compatible with the electrical programming.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: August 3, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Titkwan Hui, Robert W. Mounger
  • Patent number: 5650739
    Abstract: Digital signal delay lines with electrically programmable and trimmable delay times, including electrically erasable and reprogrammable delay times. Floating gate field effect transistors are programmed to select current, capacitance, and/or threshold and thereby set a delay time determined by acurrent charging of a capacitor up to a threshold voltage. Trimming after packaging avoids package offsets. Temperature and power supply voltage compensation by current combining gives compensation compatible with the electrical programming.
    Type: Grant
    Filed: September 26, 1994
    Date of Patent: July 22, 1997
    Assignee: Dallas Semiconductor Corporation
    Inventors: Titkwan Hui, Robert W. Mounger
  • Patent number: 5355038
    Abstract: A programmable delay line with digital input to a two-part digital-to-analog converter structure to define an equivalent resistance at a pull-down node. Preferred embodiments are configured as two identical halves. The outputs of the two halves are combined to produce an exactly symmetrical waveform. This is particularly advantageous in a programmable delay line, since this architecture assures that control changes which change the delay will not also introduce asymmetry into the output waveform.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: October 11, 1994
    Assignee: Dallas Semiconductor Corporation
    Inventor: Titkwan Hui
  • Patent number: 5160863
    Abstract: A programmable delay line with digital input to a two-part digital-to-analog converter structure to define an equivalent resistance at a pull-down node. Preferred embodiments are configured as two identical halves. The outputs of the two halves are combined to produce an exactly symmetrical waveform. This is particularly advantageous in a programmable delay line, since this architecture assures that control changes which change the delay will not also introduce asymmetry into the output waveform.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: November 3, 1992
    Assignee: Dallas Semiconductor Corporation
    Inventor: Titkwan Hui
  • Patent number: 5144173
    Abstract: A programmable delay line with digital input to a two-part digital-to-analog converter structure to define an equivalent resistance at a pull-down node. Preferred embodiments are configured as two identical halves. The outputs of the two halves are combined to produce an exactly symmetrical waveform. This is particularly advantageous in a programmable delay line, since this architecture assures that control changes which change the delay will not also introduce asymmetry into the output waveform.
    Type: Grant
    Filed: August 7, 1991
    Date of Patent: September 1, 1992
    Assignee: Dallas Semiconductor Corporation
    Inventor: Titkwan Hui