Patents by Inventor Brian Leibowitz

Brian Leibowitz 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: 20180323951
    Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.
    Type: Application
    Filed: April 10, 2018
    Publication date: November 8, 2018
    Inventors: Hae-Chang Lee, Brian Leibowitz, Jaeha Kim, Jafar Savoj
  • Patent number: 10050771
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Grant
    Filed: August 15, 2017
    Date of Patent: August 14, 2018
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Patent number: 9973328
    Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.
    Type: Grant
    Filed: July 13, 2016
    Date of Patent: May 15, 2018
    Assignee: Rambus Inc.
    Inventors: Hae-Chang Lee, Brian Leibowitz, Jaeha Kim, Jafar Savoj
  • Publication number: 20180054293
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Application
    Filed: August 15, 2017
    Publication date: February 22, 2018
    Inventors: Masum HOSSAIN, Brian Leibowitz, Jihong Ren
  • Patent number: 9843315
    Abstract: An integrated circuit includes a delay circuit and first and second interface circuits. The delay circuit delays a first timing signal by an internal delay to generate an internal timing signal. The first interface circuit communicates data to an external device in response to the internal timing signal. The second interface circuit transmits an external timing signal for capturing the data in the external device. An external delay is added to the external timing signal in the external device to generate a delayed external timing signal. The delay circuit sets the internal delay based on a comparison between the delayed external timing signal and a calibration signal transmitted by the first interface circuit.
    Type: Grant
    Filed: October 26, 2012
    Date of Patent: December 12, 2017
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Ely Tsern, Brian Leibowitz, Jared Zerbe
  • Publication number: 20170338979
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: August 7, 2017
    Publication date: November 23, 2017
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9768947
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Grant
    Filed: October 31, 2016
    Date of Patent: September 19, 2017
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Patent number: 9660844
    Abstract: A decision-feedback equalizer (DFE) samples an analog input signal against M references during the same symbol time to produce M speculative samples. Select logic in the DFE then decodes N bits resolved previously for previous symbol times to select one of the M speculative samples as the present resolved bit. The present resolved bit is then stored as the most recent previously resolved bit in preparation for the next symbol time. The select logic can be can be programmable to accommodate process, environmental, and systematic variations.
    Type: Grant
    Filed: November 11, 2015
    Date of Patent: May 23, 2017
    Assignee: Rambus Inc.
    Inventors: Brian Leibowitz, Jaeha Kim
  • Publication number: 20170134153
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Application
    Filed: October 31, 2016
    Publication date: May 11, 2017
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Publication number: 20170099132
    Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.
    Type: Application
    Filed: July 13, 2016
    Publication date: April 6, 2017
    Inventors: Hae-Chang Lee, Brian Leibowitz, Jaeha Kim, Jafar Savoj
  • Publication number: 20170054576
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 8, 2016
    Publication date: February 23, 2017
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9577816
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: February 21, 2017
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Patent number: 9565036
    Abstract: A first integrated circuit (IC) has an adjustable delay circuit and a first interface circuit. A first clock signal is provided to the adjustable delay circuit to produce a delayed clock signal provided to the first interface circuit. A second IC has a supply voltage sense circuit and a second interface circuit that transfers data with the first IC. The supply voltage sense circuit provides a noise signal to the first IC that is indicative of noise in a supply voltage of the second IC. The adjustable delay circuit adjusts a delay of the delayed clock signal based on the noise signal. In other embodiments, edge-colored clock signals reduce the effects of high frequency jitter in the transmission of data between integrated circuits (ICs) by making the high frequency jitter common between the ICs. In other embodiments, a supply voltage is used to generate clocks signals on multiple ICs.
    Type: Grant
    Filed: May 31, 2010
    Date of Patent: February 7, 2017
    Assignee: Rambus Inc.
    Inventors: Jared Zerbe, Pradeep Batra, Brian Leibowitz
  • Patent number: 9553745
    Abstract: A signaling system includes a pre-emphasizing transmitter and an equalizing receiver coupled to one another via a high-speed signal path. The receiver measures the quality of data conveyed from the transmitter. A controller uses this information and other information to adaptively establish appropriate transmit pre-emphasis and receive equalization settings, e.g. to select the lowest power setting for which the signaling system provides some minimum communication bandwidth without exceeding a desired bit-error rate.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: January 24, 2017
    Assignee: Rambus Inc.
    Inventors: Jared L. Zerbe, Fred F. Chen, Andrew Ho, Ramin Farjad-Rad, John W. Poulton, Kevin S. Donnelly, Brian Leibowitz
  • Patent number: 9455825
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: September 27, 2016
    Assignee: Rambus Inc.
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9423441
    Abstract: An integrated circuit capable of on-chip jitter tolerance measurement includes a jitter generator circuit to produce a controlled amount of jitter that is injected into at least one clock signal, and a receive circuit to sample an input signal according to the at least one clock signal. The sampled data values output from the receiver are used to evaluate the integrated circuit's jitter tolerance.
    Type: Grant
    Filed: September 17, 2012
    Date of Patent: August 23, 2016
    Assignee: Rambus Inc.
    Inventors: Hae-Chang Lee, Jaeha Kim, Brian Leibowitz
  • Patent number: 9419781
    Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.
    Type: Grant
    Filed: December 8, 2014
    Date of Patent: August 16, 2016
    Assignee: Rambus Inc.
    Inventors: Hae-Chang Lee, Brian Leibowitz, Jaeha Kim, Jafar Savoj
  • Publication number: 20160142200
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 29, 2015
    Publication date: May 19, 2016
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Publication number: 20160134442
    Abstract: A decision-feedback equalizer (DFE) samples an analog input signal against M references during the same symbol time to produce M speculative samples. Select logic in the DFE then decodes N bits resolved previously for previous symbol times to select one of the M speculative samples as the present resolved bit. The present resolved bit is then stored as the most recent previously resolved bit in preparation for the next symbol time. The select logic can be can be programmable to accommodate process, environmental, and systematic variations.
    Type: Application
    Filed: November 11, 2015
    Publication date: May 12, 2016
    Inventors: Brian Leibowitz, Jaeha Kim
  • Patent number: 9178688
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: November 3, 2015
    Assignee: Rambus Inc.
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe