Patents by Inventor Gundlapalli Shanmukha Srinivas

Gundlapalli Shanmukha Srinivas 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).

  • Open-loop correction of duty-cycle error and quadrature phase error
    Patent number: 9444442
    Abstract: A Phase Interpolator (PI) may be employed as a precisely-controlled delay element in a transmit path, for example in clock forwarded serial links. Methods and circuits are disclosed for estimating a delay needed to correct duty-cycle/and or phase errors of the received clock. These corrections or delta values may be transmitted back to the transmitter side, preferably expressed directly in terms of PI phase codes, for convenient adjustment in the transmitter clock circuitry. Various techniques also are disclosed for measuring and mitigating the effects on PI integral non-linearity.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: September 13, 2016
    Assignee: RAMBUS INC.
    Inventors: Srinivasaraman Chandrasekaran, Gundlapalli Shanmukha Srinivas
  • OPEN-LOOP CORRECTION OF DUTY-CYCLE ERROR AND QUADRATURE PHASE ERROR
    Publication number: 20140253195
    Abstract: A Phase Interpolator (PI) may be employed as a precisely-controlled delay element in a transmit path, for example in clock forwarded serial links. Methods and circuits are disclosed for estimating a delay needed to correct duty-cycle/and or phase errors of the received clock. These corrections or delta values may be transmitted back to the transmitter side, preferably expressed directly in terms of PI phase codes, for convenient adjustment in the transmitter clock circuitry. Various techniques also are disclosed for measuring and mitigating the effects on PI integral non-linearity.
    Type: Application
    Filed: January 27, 2014
    Publication date: September 11, 2014
    Applicant: RAMBUS INC.
    Inventors: Srinivasaraman Chandrasekaran, Gundlapalli Shanmukha Srinivas
  • Methods and circuits for calibrating multi-modal termination schemes
    Patent number: 8487650
    Abstract: Disclosed are methods and circuits that support different on-die termination (ODT) schemes for a plurality of signaling schemes using a relatively small number of external calibration pads. These methods and circuits develop control signals for calibrating any of multiple termination schemes that might be used by associated communication circuits. The ODT control circuits, entirely or predominantly instantiated on-die, share circuit resources employed in support of the different termination schemes to save die area.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: July 16, 2013
    Assignee: Rambus Inc.
    Inventors: Hajee Mohammed Shuaeb Fazeel, Amir Amirkhany, Gundlapalli Shanmukha Srinivas, Chaofeng Huang
  • Methods and Circuits for Calibrating Multi-Modal Termination Schemes
    Publication number: 20120187978
    Abstract: Disclosed are methods and circuits that support different on-die termination (ODT) schemes for a plurality of signaling schemes using a relatively small number of external calibration pads. These methods and circuits develop control signals for calibrating any of multiple termination schemes that might be used by associated communication circuits. The ODT control circuits, entirely or predominantly instantiated on-die, share circuit resources employed in support of the different termination schemes to save die area.
    Type: Application
    Filed: January 12, 2012
    Publication date: July 26, 2012
    Applicant: Rambus Inc.
    Inventors: Hajee Mohammed Shuaeb Fazeel, Amir Amirkhany, Gundlapalli Shanmukha Srinivas, Chaofeng Huang