Patents by Inventor Pavan Kumar Hanumolu

Pavan Kumar Hanumolu 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: 20240056085
    Abstract: Presented herein are techniques for implementing a hybrid fractional-N sampling phase locked loop with accurate digital-to-time calibration. A method includes receiving, at a comparator, an output of a sampling phase detector of a phase locked loop, the output of the sampling phase detector of the phase locked loop also being supplied as a control source for a proportional control input of a voltage-controlled oscillator, supplying an output of the comparator as an input signal to a calibration loop of a digital-to-time converter, supplying an output of the digital-to-time converter to an input of the sampling phase detector, and supplying the output of the comparator as a control source for an integral control input of the voltage-controlled oscillator.
    Type: Application
    Filed: August 15, 2022
    Publication date: February 15, 2024
    Inventors: Abhishek Bhat, Romesh Kumar Nandwana, Pavan Kumar Hanumolu, Kadaba Lakshmikumar
  • Patent number: 11901906
    Abstract: Presented herein are techniques for implementing a hybrid fractional-N sampling phase locked loop with accurate digital-to-time calibration. A method includes receiving, at a comparator, an output of a sampling phase detector of a phase locked loop, the output of the sampling phase detector of the phase locked loop also being supplied as a control source for a proportional control input of a voltage-controlled oscillator, supplying an output of the comparator as an input signal to a calibration loop of a digital-to-time converter, supplying an output of the digital-to-time converter to an input of the sampling phase detector, and supplying the output of the comparator as a control source for an integral control input of the voltage-controlled oscillator.
    Type: Grant
    Filed: August 15, 2022
    Date of Patent: February 13, 2024
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Abhishek Bhat, Romesh Kumar Nandwana, Pavan Kumar Hanumolu, Kadaba Lakshmikumar
  • Publication number: 20240039554
    Abstract: An apparatus includes a delta-sigma modulator digital-to-analog converter section having a multiple stag cascaded error cancellation architecture, each stage including a delta-sigma modulator followed by a digital-to-analog converter, the delta-sigma modulator digital-to-analog converter section configured to receive a digital input and to generate an analog output. An inverting amplifier-based analog filter is coupled to receive the analog output, the inverting amplifier-based analog filter configured to filter the analog output to produce a filtered analog output.
    Type: Application
    Filed: July 29, 2022
    Publication date: February 1, 2024
    Inventors: Bibhu Prasad Das, Romesh Kumar Nandwana, Richard Van Hoesen Booth, Pavan Kumar Hanumolu, Kadaba Lakshmikumar
  • Patent number: 11863222
    Abstract: A receiver is provided that includes a plurality of sub-rate receiver lanes each of which is configured to receive an analog receive signal from an analog front-end and produce digital sub-rate receiver data. The receiver includes one or more first digital-to-analog converters (DACs) (also referred to herein as “average” DACs) shared across the plurality of sub-rate receiver lanes, and one or more second DACs (also referred to herein as “mismatch cancellation” DACs) for each sub-rate receiver lane of the plurality of sub-rate receiver lanes. The one or more second DACs of a respective sub-rate receiver lane provide output to be combined with an output of a corresponding one of the one or more first DACs during processing of the analog receive signal in the respective sub-rate receiver lane to account for a sub-rate receiver lane specific offset with respect to a corresponding one of the one or more first DACs.
    Type: Grant
    Filed: November 17, 2021
    Date of Patent: January 2, 2024
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Romesh Kumar Nandwana, Abhishek Bhat, Kadaba Lakshmikumar, Pavan Kumar Hanumolu
  • Patent number: 11671105
    Abstract: An accurate replica oscillator-based frequency tracking loop (FTL) is provided. The replica oscillator used in the FTL can be at a lower frequency and therefore can consume much lower power compared to a main oscillator, such as an injection locked oscillator (ILO). The proposed FTL accurately sets the free running frequency of an ILO across process, voltage and temperature (PVT). Techniques are also provided to compensate the gain and offset error between the replica oscillator and the ILO.
    Type: Grant
    Filed: April 14, 2022
    Date of Patent: June 6, 2023
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Abhishek Bhat, Romesh Kumar Nandwana, Kadaba Lakshmikumar, Pavan Kumar Hanumolu
  • Publication number: 20230155618
    Abstract: A receiver is provided that includes a plurality of sub-rate receiver lanes each of which is configured to receive an analog receive signal from an analog front-end and produce digital sub-rate receiver data. The receiver includes one or more first digital-to-analog converters (DACs) (also referred to herein as “average” DACs) shared across the plurality of sub-rate receiver lanes, and one or more second DACs (also referred to herein as “mismatch cancellation” DACs) for each sub-rate receiver lane of the plurality of sub-rate receiver lanes. The one or more second DACs of a respective sub-rate receiver lane provide output to be combined with an output of a corresponding one of the one or more first DACs during processing of the analog receive signal in the respective sub-rate receiver lane to account for a sub-rate receiver lane specific offset with respect to a corresponding one of the one or more first DACs.
    Type: Application
    Filed: November 17, 2021
    Publication date: May 18, 2023
    Inventors: Romesh Kumar Nandwana, Abhishek Bhat, Kadaba Lakshmikumar, Pavan Kumar Hanumolu
  • Publication number: 20230119570
    Abstract: An accurate replica oscillator-based frequency tracking loop (FTL) is provided. The replica oscillator used in the FTL can be at a lower frequency and therefore can consume much lower power compared to a main oscillator, such as an injection locked oscillator (ILO). The proposed FTL accurately sets the free running frequency of an ILO across process, voltage and temperature (PVT). Techniques are also provided to compensate the gain and offset error between the replica oscillator and the ILO.
    Type: Application
    Filed: April 14, 2022
    Publication date: April 20, 2023
    Inventors: Abhishek Bhat, Romesh Kumar Nandwana, Kadaba Lakshmikumar, Pavan Kumar Hanumolu
  • Patent number: 11356107
    Abstract: An accurate replica oscillator-based frequency tracking loop (FTL) is provided. The replica oscillator used in the FTL can be at a lower frequency and therefore can consume much lower power compared to a main oscillator, such as an injection locked oscillator (ILO). The proposed FTL accurately sets the free running frequency of an ILO across process, voltage and temperature (PVT). Techniques are also provided to compensate the gain and offset error between the replica oscillator and the ILO.
    Type: Grant
    Filed: October 15, 2021
    Date of Patent: June 7, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Abhishek Bhat, Romesh Kumar Nandwana, Kadaba Lakshmikumar, Pavan Kumar Hanumolu
  • Publication number: 20090197552
    Abstract: The present invention relates generally to a bandwidth tunable mixer and more particularly but not exclusively to a mixer having a bandwidth that is tunable in response to a variation in the duty-cycle of a local oscillator.
    Type: Application
    Filed: January 6, 2009
    Publication date: August 6, 2009
    Inventors: Peter Kurahashi, Pavan Kumar Hanumolu, Un-Ku Moon