Patents by Inventor Colin Whitfield

Colin Whitfield 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).

  • Publication number: 20230178962
    Abstract: Systems and methods for controlling laser modulation in burst communications. In a start-up phase, a drive circuitry sequentially applies first and second drive currents to a laser diode such that it produces a first and second optical output, respectively. A compensating current source coupled to the laser diode provides a current related to the first and second drive currents to maintain a combined current flowing through an impedance connected to the laser diode at a substantially constant level during the start-up phase. An optical sensor measures the first and second optical outputs, and a controller uses values of the first and second drive currents, the outputs from the optical sensor, and at least one supplied input value to provide control values for the drive circuitry for controlling operating current of the laser diode during a subsequent operating phase, wherein information is transmitted in at least one burst.
    Type: Application
    Filed: December 2, 2022
    Publication date: June 8, 2023
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield
  • Patent number: 10749605
    Abstract: A system for transmitting a sequence of at least two data bursts in a fibre optical communications system includes: selection circuitry configured to select one of a data input value, a logical high value or a logical low value such that the selection circuitry selects the data input value during a data transmission period during a defined burst period and selects one of the logical high value and the logical low value during an extension time period during the defined burst period and immediately following the data transmission period, such that for the sequence of at least two bursts, at least one burst has a logical low value extension period and at least one burst has a logical high value extension period; drive circuitry configured to apply a current to a laser diode, the current corresponding to the value selected by the selection circuitry during the defined burst period or a zero value otherwise, the current being such that the laser diode is configured to provide an optical output; an optical sensor
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: August 18, 2020
    Assignee: HiLight Semiconductor Limited
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield
  • Patent number: 10535978
    Abstract: A system for controlling an optical intensity and modulation of an optical data transmitter which includes current driver circuitry configured to provide a drive current to a laser diode wherein said current comprises a fixed component and a modulated component, said modulated component having a magnitude related to an input data stream. The monitor circuitry contains a photodiode and a first transimpedance amplifier coupled to said photodiode, said monitor circuitry configured to provide an output signal related to an optical intensity of said laser diode. The system further includes replica monitor circuitry containing a replica capacitor with a replica capacitance and a second transimpedance amplifier configured to be substantially identical in construction to said first transimpedance amplifier, said second transimpedance amplifier coupled to said replica capacitor.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: January 14, 2020
    Assignee: HILIGHT SEMICONDUCTOR LIMITED
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield, Christian Rookes, Derek Hutchins, George Brocklehurst
  • Patent number: 10447007
    Abstract: A system comprising drive circuitry configured to apply in a start-up phase a first drive current and then a second different drive current to a laser diode, the first drive current and second drive current being such that the laser diode is configured to provide a first optical output and a second optical output respectively. The system further comprising an optical sensor configured to provide a first sensor output corresponding to the first optical output of the laser diode and a second sensor output corresponding to the second optical output. The system further comprises a controller configured to use a value of the first drive current, a value of the second drive current, the first sensor output, the second sensor output and at least one supplied input value to provide control values for the drive circuitry to control an operating current of the laser diode, wherein the system is arranged to be used in a communication system wherein information is transmitted in at least one burst.
    Type: Grant
    Filed: June 17, 2016
    Date of Patent: October 15, 2019
    Assignee: HILIGHT SEMICONDUCTOR LIMITED
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield
  • Publication number: 20190089464
    Abstract: A system for transmitting a sequence of at least two data bursts in a fibre optical communications system includes: selection circuitry configured to select one of a data input value, a logical high value or a logical low value such that the selection circuitry selects the data input value during a data transmission period during a defined burst period and selects one of the logical high value and the logical low value during an extension time period during the defined burst period and immediately following the data transmission period, such that for the sequence of at least two bursts, at least one burst has a logical low value extension period and at least one burst has a logical high value extension period; drive circuitry configured to apply a current to a laser diode, the current corresponding to the value selected by the selection circuitry during the defined burst period or a zero value otherwise, the current being such that the laser diode is configured to provide an optical output; an optical sensor
    Type: Application
    Filed: November 5, 2018
    Publication date: March 21, 2019
    Applicant: HiLight Semiconductor Limited
    Inventors: William REDMAN-WHITE, Dominique COUE, Colin WHITFIELD
  • Patent number: 10205532
    Abstract: A laser power controller employs: selection circuitry configured to select one of a data input value, a logical high value or a logical low value such that the selection circuitry selects the data input value during a data transmission period during a defined burst period and selects one of the logical high value and the logical low value during an extension time period during the defined burst period and immediately following the data transmission period; drive circuitry configured to apply, to a laser diode, a current corresponding to the value selected by the selection circuitry during the defined burst period or a zero value otherwise, the current being such that the laser diode is configured to provide an optical output; an optical sensor module configured to provide a sensor module output corresponding to the optical output of the laser diode, and configured to provide an electrical output proportional to the laser diode's optical output corresponding to the logical high value or the logical low value;
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: February 12, 2019
    Assignee: HILIGHT SEMICONDUCTOR LIMITED
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield
  • Publication number: 20180219354
    Abstract: A system for controlling an optical intensity and modulation of an optical data transmitter which includes current driver circuitry configured to provide a drive current to a laser diode wherein said current comprises a fixed component and a modulated component, said modulated component having a magnitude related to an input data stream. The monitor circuitry contains a photodiode and a first transimpedance amplifier coupled to said photodiode, said monitor circuitry configured to provide an output signal related to an optical intensity of said laser diode. The system further includes replica monitor circuitry containing a replica capacitor with a replica capacitance and a second transimpedance amplifier configured to be substantially identical in construction to said first transimpedance amplifier, said second transimpedance amplifier coupled to said replica capacitor.
    Type: Application
    Filed: January 30, 2018
    Publication date: August 2, 2018
    Applicant: Hilight Semiconductor Limited
    Inventors: William REDMAN-WHITE, Dominique COUE, Colin WHITFIELD, Christian ROOKES, Derek HUTCHINS, George BROCKLEHURST
  • Publication number: 20180019823
    Abstract: A laser power controller employs: selection circuitry configured to select one of a data input value, a logical high value or a logical low value such that the selection circuitry selects the data input value during a data transmission period during a defined burst period and selects one of the logical high value and the logical low value during an extension time period during the defined burst period and immediately following the data transmission period; drive circuitry configured to apply, to a laser diode, a current corresponding to the value selected by the selection circuitry during the defined burst period or a zero value otherwise, the current being such that the laser diode is configured to provide an optical output; an optical sensor module configured to provide a sensor module output corresponding to the optical output of the laser diode, and configured to provide an electrical output proportional to the laser diode's optical output corresponding to the logical high value or the logical low value;
    Type: Application
    Filed: July 7, 2017
    Publication date: January 18, 2018
    Applicant: Hilight Semiconductor Limited
    Inventors: William REDMAN-WHITE, Dominique COUE, Colin WHITFIELD
  • Publication number: 20160372887
    Abstract: A system having: drive circuitry configured to apply in a start-up phase a first drive current and then a second different drive current to a laser diode, said first drive current and second drive current being such that said laser diode is configured to provide a first optical output and a second optical output respectively; an optical sensor configured to provide a first sensor output corresponding to said first optical output of said laser diode and a second sensor output corresponding to said second optical output; and a controller configured to use a value of said first drive current, a value of said second drive current, said first sensor output, said second sensor output and at least one supplied input value to provide control values for said drive circuitry to control an operating current of said laser diode, wherein said system is arranged to be used in a communication system wherein information is transmitted in at least one burst.
    Type: Application
    Filed: June 17, 2016
    Publication date: December 22, 2016
    Applicant: Hilight Semiconductor LImited
    Inventors: William REDMAN-WHITE, Dominique COUE, Colin WHITFIELD
  • Patent number: 5764097
    Abstract: A voltage level converter having: an input bias terminal; connect to first, second and third voltage sources; first and second complementary output terminals; and an input control terminal wherein, said input bias terminal is connected to a third output terminal of an automatic bias stage, said bias stage having connections to said voltage sources for providing substantially said first low voltage to said third output terminal in the absence of said second high voltage and providing a third voltage that is greater than said first low voltage when said second high voltage is present, said third voltage being derived from said second high voltage.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: June 9, 1998
    Assignee: SGS-Thomson Microelectronics Limited
    Inventor: Colin Whitfield
  • Patent number: 5726936
    Abstract: A capacitive load such as the array ground line of a flash memory is initially pulled up towards a positive voltage via a first relatively weak current source, and subsequently a stronger source is switched to the load. To pull the load down, the pull up sources are turned off, and a relatively weak pull-down current source switched to the load. Subsequently a stronger pull-down source is switched to the load.The arrangement may avoid high transient currents while ensuring adequate quiescent sourcing ability.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: March 10, 1998
    Assignee: SGS-Thomson Microelectronics Limited
    Inventor: Colin Whitfield