Patents by Inventor Michael S. Harwood

Michael S. Harwood 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: 10771065
    Abstract: The present invention is directed to electrical circuits. More specifically, embodiments of the present invention provide a charge pump, which can be utilized as a part of a clock data recovery device. Early and late signals are used as differential switching voltage signals in the charge pump. The first switch and a second switch are used for controlling the direction of the current flowing into the loop filter. Input differential voltages to the switches are being generated with an opamp negative feedback loop. The output voltage of the first switch and the second switch is used in conjunction with a resistor to generate a charge pump current. There are other embodiments as well.
    Type: Grant
    Filed: October 25, 2019
    Date of Patent: September 8, 2020
    Assignee: INPHI CORPORATION
    Inventors: Simon Forey, Parmanand Mishra, Michael S. Harwood, Rajasekhar Nagulapalli
  • Publication number: 20200059348
    Abstract: The present invention is directed to electrical circuits. More specifically, embodiments of the present invention provide a charge pump, which can be utilized as a part of a clock data recovery device. Early and late signals are used as differential switching voltage signals in the charge pump. The first switch and a second switch are used for controlling the direction of the current flowing into the loop filter. Input differential voltages to the switches are being generated with an opamp negative feedback loop. The output voltage of the first switch and the second switch is used in conjunction with a resistor to generate a charge pump current. There are other embodiments as well.
    Type: Application
    Filed: October 25, 2019
    Publication date: February 20, 2020
    Inventors: Simon FOREY, Parmanand MISHRA, Michael S. HARWOOD, Rajasekhar NAGULAPALLI
  • Patent number: 10498526
    Abstract: The present invention is directed to electrical circuits. More specifically, embodiments of the present invention provide a charge pump, which can be utilized as a part of a clock data recovery device. Early and late signals are used as differential switching voltage signals in the charge pump. The first switch and a second switch are used for controlling the direction of the current flowing into the loop filter. Input differential voltages to the switches are being generated with an opamp negative feedback loop. The output voltage of the first switch and the second switch is used in conjunction with a resistor to generate a charge pump current. There are other embodiments as well.
    Type: Grant
    Filed: February 8, 2019
    Date of Patent: December 3, 2019
    Assignee: INPHI CORPORATION
    Inventors: Simon Forey, Parmanand Mishra, Michael S. Harwood, Rajasekhar Nagulapalli
  • Patent number: 10193640
    Abstract: The present invention is directed to data communication. According to a specific embodiment, the present invention provides technique for loss of signal detection. A loss-of-signal detection (LOSD) device determines an analog signal indicating signal strength by subtracting a threshold offset voltage from an incoming signal. The analog signal is then processed by a switch network of an output stage circuit, which provides a digital output of loss of signal indication at a low frequency (relative to the incoming signal frequency). There are other embodiments as well.
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: January 29, 2019
    Assignee: INPHI CORPORATION
    Inventors: Simon Forey, Rajasekhar Nagulapalli, Parmanand Mishra, Michael S. Harwood
  • Publication number: 20180294899
    Abstract: The present invention is directed to data communication. According to a specific embodiment, the present invention provides technique for loss of signal detection. A loss-of-signal detection (LOSD) device determines an analog signal indicating signal strength by subtracting a threshold offset voltage from an incoming signal. The analog signal is then processed by a switch network of an output stage circuit, which provides a digital output of loss of signal indication at a low frequency (relative to the incoming signal frequency). There are other embodiments as well.
    Type: Application
    Filed: May 31, 2018
    Publication date: October 11, 2018
    Inventors: Simon FOREY, Rajasekhar NAGULAPALLI, Parmanand MISHRA, Michael S. HARWOOD
  • Patent number: 10014965
    Abstract: The present invention is directed to data communication. According to a specific embodiment, the present invention provides technique for loss of signal detection. A loss-of-signal detection (LOSD) device determines an analog signal indicating signal strength by subtracting a threshold offset voltage from an incoming signal. The analog signal is then processed by a switch network of an output stage circuit, which provides a digital output of loss of signal indication at a low frequency (relative to the incoming signal frequency). There are other embodiments as well.
    Type: Grant
    Filed: November 4, 2016
    Date of Patent: July 3, 2018
    Assignee: INPHI CORPORATION
    Inventors: Simon Forey, Rajasekhar Nagulapalli, Parmanand Mishra, Michael S. Harwood
  • Patent number: 9853842
    Abstract: The present invention is directed to data communication systems and methods. More specifically, embodiments of the present invention provide a CML that uses one or more equalization modules to apply equalization via secondary windings of transformers that are coupled, directly or indirectly, to the CML outputs. The equalization modules comprises a DAC component that generates switching signals based on control signals received from an external equalization module. The equalization module also includes switchable resistors and/or capacitors. The switching signals are used to select switchable resistors and/or capacitors. By switching resistors and/or capacitors at the equalization module, the outputs of the CML are equalized. There are other embodiments as well.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: December 26, 2017
    Assignee: INPHI CORPORATION
    Inventors: Parmanand Mishra, Steffen Nielsen, Michael S. Harwood
  • Publication number: 20170078120
    Abstract: The present invention is directed to data communication systems and methods. More specifically, embodiments of the present invention provide a CML that uses one or more equalization modules to apply equalization via secondary windings of transformers that are coupled, directly or indirectly, to the CML outputs. The equalization modules comprises a DAC component that generates switching signals based on control signals received from an external equalization module. The equalization module also includes switchable resistors and/or capacitors. The switching signals are used to select switchable resistors and/or capacitors. By switching resistors and/or capacitors at the equalization module, the outputs of the CML are equalized. There are other embodiments as well.
    Type: Application
    Filed: November 22, 2016
    Publication date: March 16, 2017
    Inventors: Parmanand MISHRA, Steffen NIELSEN, Michael S. HARWOOD
  • Patent number: 9537685
    Abstract: The present invention is directed to data communication systems and methods. More specifically, embodiments of the present invention provide a CML that uses one or more equalization modules to apply equalization via secondary windings of transformers that are coupled, directly or indirectly, to the CML outputs. The equalization modules comprises a DAC component that generates switching signals based on control signals received from an external equalization module. The equalization module also includes switchable resistors and/or capacitors. The switching signals are used to select switchable resistors and/or capacitors. By switching resistors and/or capacitors at the equalization module, the outputs of the CML are equalized. There are other embodiments as well.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: January 3, 2017
    Assignee: INPHI CORPORATION
    Inventors: Parmanand Mishra, Steffen Nielsen, Michael S. Harwood
  • Patent number: 9485122
    Abstract: The present invention is directed to data communication systems and methods. In various embodiments, the present invention provides a CML device that changes output frequency response by varying resistance values of its load resistance and source resistance. A bias control voltage is used to adjust the tail current of the CML device, and the tail current adjusts the output gain of the CML device. There are other embodiments as well.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: November 1, 2016
    Assignee: INPHI CORPORATION
    Inventors: Parmanand Mishra, Michael S. Harwood
  • Publication number: 20160301549
    Abstract: The present invention is directed to data communication systems and methods. In various embodiments, the present invention provides a CML device that changes output frequency response by varying resistance values of its load resistance and source resistance. A bias control voltage is used to adjust the tail current of the CML device, and the tail current adjusts the output gain of the CML device. There are other embodiments as well.
    Type: Application
    Filed: November 23, 2015
    Publication date: October 13, 2016
    Inventors: Parmanand MISHRA, Michael S. HARWOOD
  • Publication number: 20160294582
    Abstract: The present invention is directed to data communication systems and methods. More specifically, embodiments of the present invention provide a CML that uses one or more equalization modules to apply equalization via secondary windings of transformers that are coupled, directly or indirectly, to the CML outputs. The equalization modules comprises a DAC component that generates switching signals based on control signals received from an external equalization module. The equalization module also includes switchable resistors and/or capacitors. The switching signals are used to select switchable resistors and/or capacitors. By switching resistors and/or capacitors at the equalization module, the outputs of the CML are equalized. There are other embodiments as well.
    Type: Application
    Filed: March 18, 2016
    Publication date: October 6, 2016
    Inventors: Parmanand MISHRA, Steffen NIELSEN, Michael S. HARWOOD
  • Patent number: 9325319
    Abstract: The present invention is directed to data communication systems and methods. More specifically, embodiments of the present invention provide a CML that uses one or more equalization modules to apply equalization via secondary windings of transformers that are coupled, directly or indirectly, to the CML outputs. The equalization modules comprises a DAC component that generates switching signals based on control signals received from an external equalization module. The equalization module also includes switchable resistors and/or capacitors. The switching signals are used to select switchable resistors and/or capacitors. By switching resistors and/or capacitors at the equalization module, the outputs of the CML are equalized. There are other embodiments as well.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: April 26, 2016
    Assignee: INPHI CORPORATION
    Inventors: Parmanand Mishra, Steffen Nielsen, Michael S. Harwood
  • Patent number: 9225560
    Abstract: The present invention is directed to data communication systems and methods. In various embodiments, the present invention provides a CML device that changes output frequency response by varying resistance values of its load resistance and source resistance. A bias control voltage is used to adjust the tail current of the CML device, and the tail current adjusts the output gain of the CML device. There are other embodiments as well.
    Type: Grant
    Filed: April 8, 2015
    Date of Patent: December 29, 2015
    Assignee: INPHI CORPORATION
    Inventors: Parmanand Mishra, Michael S. Harwood
  • Patent number: 8964820
    Abstract: The present invention is directed to integrated circuits. In a specific embodiment, high frequency signals from an equalizer are directly connected to a first pair of inputs of a sense amplifier. The sense amplifier also has a second pair of inputs, which can be selectively coupled to output signals from a DAC or high frequency loopback signals. There are other embodiments as well.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: February 24, 2015
    Assignee: Inphi Corporation
    Inventors: Parmanand Mishra, Michael S. Harwood
  • Publication number: 20150016493
    Abstract: The present invention is directed to integrated circuits. In a specific embodiment, high frequency signals from an equalizer are directly connected to a first pair of inputs of a sense amplifier. The sense amplifier also has a second pair of inputs, which can be selectively coupled to output signals from a DAC or high frequency loopback signals. There are other embodiments as well.
    Type: Application
    Filed: September 5, 2014
    Publication date: January 15, 2015
    Inventors: Parmanand MISHRA, Michael S. HARWOOD
  • Patent number: 8855176
    Abstract: The present invention is directed to integrated circuits. In a specific embodiment, high frequency signals from an equalizer are directly connected to a first pair of inputs of a sense amplifier. The sense amplifier also has a second pair of inputs, which can be selectively coupled to output signals from a DAC or high frequency loopback signals. There are other embodiments as well.
    Type: Grant
    Filed: April 18, 2014
    Date of Patent: October 7, 2014
    Assignee: Inphi Corporation
    Inventors: Parmanand Mishra, Michael S. Harwood
  • Patent number: 8731031
    Abstract: The present invention is directed to integrated circuits. In a specific embodiment, high frequency signals from an equalizer is directly connected to a first pair of inputs of a sense amplifier. The sense amplifier also has a second pair of inputs, which can be selectively coupled to output signals from a DAC or high frequency loopback signals. There are other embodiments as well.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: May 20, 2014
    Assignee: Inphi Corporation
    Inventors: Parmanand Mishra, Michael S. Harwood
  • Patent number: 8040973
    Abstract: The present invention relates to pre-distortion in transmitter circuits and provides a circuit for introducing pre-distortion into the output of a transmitter, wherein said pre-distortion comprises a pre-cursor, a cursor and a post-cursor, the circuit comprising: a first driver arranged to switch an output drive between said pre-cursor and said cursor; a second driver arranged to switch an output drive between said post-cursor and said cursor; a third driver arranged to switch an output drive between a positive cursor drive and a negative cursor drive. The arrangement provided give flexibility when setting the pre-cursor, cursor and post-cursor levels.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: October 18, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Michael S. Harwood, Andre Szczepanek, Derek Colman
  • Publication number: 20080219390
    Abstract: A thermometer code to sign and magnitude converter that is particularly useful in a flash ADC is provided. This comprises two conversion units. The first is a thermometer code to Gray code converter and the second a Gray code to sign and magnitude converter. Preferably, the Gray code is of a kind that has a sign bit and has the other bits symmetrically disposed about zero. This form is easily converted to a sign and magnitude code, which is advantageous as it reduces the latency of the converter, which is particularly useful at high data rates.
    Type: Application
    Filed: February 8, 2008
    Publication date: September 11, 2008
    Inventors: Richard D. Simpson, Michael S. Harwood, Patrick W. Bosshart