Patents by Inventor Anirudh

Anirudh 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: 7561483
    Abstract: An internally asymmetric method for evaluating static memory cell dynamic stability provide a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the internal symmetry of a static random access memory (SRAM) memory cell, operating the cell and observing changes in performance caused by the asymmetric operation, the dynamic stability of the SRAM cell can be studied over designs and operating environments. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each cross-coupled stage. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. A memory array with at least one test cell can be fabricated in a production or test wafer and internal nodes of the memory cell can be probed to provide further information.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7558136
    Abstract: A memory cell having an asymmetric connection for evaluating dynamic stability provides a mechanism for raising the performance of memory arrays beyond present levels/yields. By operating the cell and observing changes in performance caused by the asymmetry, the dynamic stability of the SRAM cell can be studied over designs and operating environments. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each crosscoupled stage. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. A memory array with at least one test cell can be fabricated in a production or test wafer and internal nodes of the memory cell can be probed to provide further information.
    Type: Grant
    Filed: August 14, 2007
    Date of Patent: July 7, 2009
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7515491
    Abstract: A method for evaluating leakage effects on static memory cell access time provides a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the states of other static memory cells connected to the same bitline as a static memory cell under test, the effect of leakage on the access time of the cell can be observed. The leakage effects can further be observed while varying the internal symmetry of the memory cell, operating the cell and observing changes in performance caused by the asymmetric operation. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each cross-coupled stage.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: April 7, 2009
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Publication number: 20090084641
    Abstract: Wheel cylinder based auto adjuster incorporated within the wheel cylinder housing, comprising a (13) housing, (12) lip seal, (10) plunger, (4) adjuster, (6) adjusting screws, (3) dust cover, (2) a cam screw, (9) copper washer, (8) thrust bearing and (7) excluder assembly characterized in that the said adjusting screw and adjuster being connected by means of (15) threaded joint roller.
    Type: Application
    Filed: April 21, 2008
    Publication date: April 2, 2009
    Applicant: BRAKES INDIA LIMITED
    Inventors: Malaiappan Viswanathan, Thiruvananthaperumal Dharmar, R. Srinivasa Rao, Tvr Anirudh
  • Patent number: 7483322
    Abstract: A ring oscillator row circuit for evaluating memory cell performance provides for circuit delay and performance measurements in an actual memory circuit environment. A ring oscillator is implemented with a row of memory cells and has outputs connected to one or more bitlines along with other memory cells that are substantially identical to the ring oscillator cells. Logic may be included for providing a fully functional memory array, so that the cells other than the ring oscillator cells can be used for storage when the ring oscillator row wordlines are disabled. One or both power supply rails of individual cross-coupled inverter stages forming static memory cells used in the ring oscillator circuit may be isolated from each other in order to introduce a voltage asymmetry so that circuit asymmetry effects on delay can be evaluated.
    Type: Grant
    Filed: December 22, 2007
    Date of Patent: January 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Yuen H. Chan, Anirudh Devgan
  • Publication number: 20090002213
    Abstract: A method of digitizing an analog signal is provided, comprising the steps of separating the analog signal spanning a frequency range into a plurality of frequency bands, each frequency band spanning a corresponding predefined frequency range, at least a portion of each of the plurality of corresponding frequency ranges not overlapping any other of the plurality of corresponding predefined frequency ranges and then translating at least one of the signals in the plurality of frequency bands to a lower frequency band in accordance with a local oscillator and digitizing the at least one translated signal with digitizing elements having a frequency range less than the analog signal frequency range. A fixed relationship of the phase of the local oscillator and a repetitive signal generated in accordance with a writing to a circular buffer of the digitized representation of the at least one of the plurality of frequency bands is then defined.
    Type: Application
    Filed: April 30, 2008
    Publication date: January 1, 2009
    Applicant: LeCroy Corporation
    Inventors: Francois LaMarche, Laxmikant Joshi, Anirudh Sureka
  • Publication number: 20080319717
    Abstract: An efficient method and computer program for modeling and improving stating memory performance across process variations and environmental conditions provides a mechanism for raising the performance of memory arrays beyond present levels/yields. Statistical (Monte-Carlo) analyses of subsets of circuit parameters are performed for each of several memory performance variables and then sensitivities of each performance variable to each of the circuit parameters are determined. The memory cell design parameters and/or operating conditions of the memory cells are then adjusted in conformity with the sensitivities, resulting in improved memory yield and/or performance. Once a performance level is attained, the sensitivities can then be used to alter the probability distributions of the performance variables to achieve a higher yield.
    Type: Application
    Filed: August 27, 2008
    Publication date: December 25, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Rajiv V. Joshi, Anirudh Devgan
  • Patent number: 7434188
    Abstract: A system and a method are disclosed for integrating the results of lithographic simulation into the physical synthesis process. The effects of lithographic variation are considered when selecting a cell from among a group of cells having equivalent function. Circuit design elements are placed and routed with consideration of the effects of lithographic variation on robustness, timing performance, and leakage current. Cells may be simulated under a variety of conditions and environments and the simulation results stored in a library for efficient lithographically optimized placements.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: October 7, 2008
    Assignee: Magma Design Automation, Inc.
    Inventors: Anirudh Devgan, Roderick Metcalfe, Vivek Raghavan, Alfred Wong
  • Patent number: 7376001
    Abstract: A method for evaluating memory cell performance provides for circuit delay and performance measurements in an actual memory circuit environment. A ring oscillator implemented in a row of memory cells and having outputs connected to one or more bitlines along with other memory cells that are substantially identical to the ring oscillator cells is operated by the method. Logic may be included for providing a fully functional memory array, so that the cells other than the ring oscillator cells can be used for storage when the ring oscillator row wordlines are disabled. One or both power supply rails of individual cross-coupled inverter stages forming static memory cells used in the ring oscillator circuit may be isolated from each other in order to introduce a voltage asymmetry so that circuit asymmetry effects on delay can be evaluated.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: May 20, 2008
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Yuen H. Chan, Anirudh Devgan
  • Publication number: 20080094878
    Abstract: A ring oscillator row circuit for evaluating memory cell performance provides for circuit delay and performance measurements in an actual memory circuit environment. A ring oscillator is implemented with a row of memory cells and has outputs connected to one or more bitlines along with other memory cells that are substantially identical to the ring oscillator cells. Logic may be included for providing a fully functional memory array, so that the cells other than the ring oscillator cells can be used for storage when the ring oscillator row wordlines are disabled. One or both power supply rails of individual cross-coupled inverter stages forming static memory cells used in the ring oscillator circuit may be isolated from each other in order to introduce a voltage asymmetry so that circuit asymmetry effects on delay can be evaluated.
    Type: Application
    Filed: December 22, 2007
    Publication date: April 24, 2008
    Inventors: Rajiv Joshi, Qiuyi Ye, Yuen Chan, Anirudh Devgan
  • Publication number: 20080052646
    Abstract: A method for performing leakage analysis includes receiving information specifying an integrated circuit. A neighborhood of shapes associated with the integrated circuit is then determined. Leakage information associated with the integrated circuit is generated based on the neighborhood of shapes. The neighborhood of shapes may be determined by determining a first set of spacings to a boundary of a first cell from an internal shape. A second set of spacings may be determined from the boundary of the first cell to a shape of a second cell. A lithography process may be characterized using the first and second set of spacings.
    Type: Application
    Filed: July 20, 2007
    Publication date: February 28, 2008
    Applicant: Magma Design Automation, Inc.
    Inventors: Emre Tuncer, Hui Zheng, Vivek Raghavan, Anirudh Devgan, Amir Ajami, Alessandra Nardi, Tao Lin, Pramod Thazhathethil, Alfred Wong
  • Publication number: 20080052653
    Abstract: A method for performing timing analysis includes receiving information specifying an integrated circuit. A neighborhood of shapes associated with the integrated circuit is then determined. Delay information associated with the integrated circuit is generated based on the neighborhood of shapes. The neighborhood of shapes may be determined by determining a first set of spacings to a boundary of a first cell from an internal shape. A second set of spacings may be determined from the boundary of the first cell to a shape of a second cell. A lithography process may be characterized using the first and second set of spacings.
    Type: Application
    Filed: July 20, 2007
    Publication date: February 28, 2008
    Applicant: Magma Design Automation, Inc.
    Inventors: Emre Tuncer, Hui Zheng, Vivek Raghavan, Anirudh Devgan, Amir Ajami, Alessandra Nardi, Tao Lin, Pramod Thazhathethil, Alfred Wong
  • Publication number: 20080039547
    Abstract: The invention relates to a novel poly(ethylene oxide)imine; a novel amine reactive moiety; a novel moisture activated latent curing adhesive or sealant mixture comprising (1) a ketimine or aldimine, and (2) an amine reactive moiety; and a novel moisture activated latent curing adhesive or sealant comprising the reaction product of (1) and (2).
    Type: Application
    Filed: August 9, 2006
    Publication date: February 14, 2008
    Inventors: Chetan Anirudh Khatri, Joseph Zavatsky, Binoy K. Bordoloi
  • Publication number: 20080028463
    Abstract: A system and method for detecting a first network of compromised computers in a second network of computers, comprising: collecting Domain Name System (DNS) data for the second network; examining the collected data relative to DNS data from known comprised and/or uncompromised computers in the second network; and determining the existence of the first network and/or the identity of compromised computers in the second network based on the examination.
    Type: Application
    Filed: October 3, 2006
    Publication date: January 31, 2008
    Applicant: Damballa, Inc.
    Inventors: David Dagon, Nick Feamster, Weake Lee, Robert Edmonds, Richard Lipton, Anirudh Ramachandran
  • Publication number: 20080017591
    Abstract: The invention disclosed provides an apparatus and method for filtration and disinfection of ship's ballast water, such as sea water, based on hydrodynamic cavitation. The apparatus comprises a vortex diode with a tangential entry port and an axial outlet port with single or multiple bleeding holes. The disinfected water may be re-circulated through the system for additional disinfection or released from the tank into the surrounding waterways. The disinfection of seawater/ship's ballast water is achieved through filtration and hydrodynamic cavitation and the method does not involve use of any chemicals or any chemical reaction. The invented apparatus and method is simple, eco-friendly and can be fitted on to existing intake and discharge systems of any ship with minor modifications. It poses no risk to the health of the ship's crew unlike chemical methods and requires no special skill or additional manpower for its operation.
    Type: Application
    Filed: March 20, 2007
    Publication date: January 24, 2008
    Applicant: COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH
    Inventors: Vivek Ranade, Anirudh Pandit, Arga Anil, Subhash Sawant, Dandayudapani Ilangovan, Rajachandran Madhan, Krishnamurthy Pilarisetty Venkat
  • Publication number: 20070300191
    Abstract: A method of modeling electromagnetism in an irregular conductive plane, by dividing the surface into a grid of unequal and unaligned rectangles, assigning a circuit node location to a center of each rectangle, and calculating capacitive and inductive parameters based on the center circuit node locations. Rectangulation is accomplished using automated, recursive bisection. Capacitive segments are assigned to each circuit node and coincide with the corresponding rectangles. Inductive segments are assigned between adjacent rectangle pairs, with a width of an inductive segment defined as the common boundary of the corresponding pair of rectangles and the length of the inductive segment defined as the normal distance between circuit nodes of the two rectangles. Placement of the circuit nodes at the centers of the rectangles significantly reduces the number of nodes and segments, and provides a faster yet comprehensive analysis framework.
    Type: Application
    Filed: September 3, 2007
    Publication date: December 27, 2007
    Inventors: Michael Beattie, Anirudh Devgan, Byron Krauter, Hui Zheng
  • Publication number: 20070291562
    Abstract: Internally asymmetric methods and circuits for evaluating static memory cell dynamic stability provide a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the internal symmetry of a static random access memory (SRAM) memory cell, operating the cell and observing changes in performance caused by the asymmetric operation, the dynamic stability of the SRAM cell can be studied over designs and operating environments. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each cross-coupled stage. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. A memory array with at least one test cell can be fabricated in a production or test wafer and internal nodes of the memory cell can be probed to provide further information.
    Type: Application
    Filed: August 14, 2007
    Publication date: December 20, 2007
    Inventors: Rajiv Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7304895
    Abstract: Bitline variable methods and circuits for evaluating static memory cell dynamic stability provide a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the bitline pre-charge voltage of a static random access memory (SRAM) memory cell, operating the cell and observing changes in performance caused by the changes in the bitline voltage, the dynamic stability of the SRAM cell can be studied over designs and operating environments. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. In addition, cell power supply voltages can be split and set to different levels in order to study the effect of cell asymmetry in combination with bitline pre-charge voltage differences.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: December 4, 2007
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7301835
    Abstract: Internally asymmetric methods and circuits for evaluating static memory cell dynamic stability provide a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the internal symmetry of a static random access memory (SRAM) memory cell, operating the cell and observing changes in performance caused by the asymmetric operation, the dynamic stability of the SRAM cell can be studied over designs and operating environments. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each cross-coupled stage. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. A memory array with at least one test cell can be fabricated in a production or test wafer and internal nodes of the memory cell can be probed to provide further information.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: November 27, 2007
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7302661
    Abstract: A method of modeling electromagnetism in an irregular conductive plane, by dividing the surface into a grid of unequal and unaligned rectangles, assigning a circuit node location to a center of each rectangle, and calculating capacitive and inductive parameters based on the center circuit node locations. Rectangulation is accomplished using automated, recursive bisection. Capacitive segments are assigned to each circuit node and coincide with the corresponding rectangles. Inductive segments are assigned between adjacent rectangle pairs, with a width of an inductive segment defined as the common boundary of the corresponding pair of rectangles and the length of the inductive segment defined as the normal distance between circuit nodes of the two rectangles. Placement of the circuit nodes at the centers of the rectangles significantly reduces the number of nodes and segments, and provides a faster yet comprehensive analysis framework.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: November 27, 2007
    Assignee: International Business Machines Corporation
    Inventors: Michael W. Beattie, Anirudh Devgan, Byron L. Krauter, Hui Zheng