Patents by Inventor Gregory M. Schaeffer

Gregory M. Schaeffer 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: 10606970
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In one example according to aspects of the present disclosure, a computer-implemented method is provided. The method comprises performing an initial statistical static timing analysis of the integrated circuit to create a parameterized model of the integrated circuit for a plurality of paths using a plurality of timing corners to calculate a timing value for each of the plurality of paths, each of the plurality of timing corners representing a set of timing performance parameters. The method further comprises determining at least one worst timing corner from the parameterized model for each of the plurality of paths based on the initial statistical static timing analysis and calculated timing value for each of the plurality of paths. The method also comprises performing a subsequent analysis of the integrated circuit using the at least one worst timing corner.
    Type: Grant
    Filed: April 12, 2018
    Date of Patent: March 31, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Alexander J. Suess, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Patent number: 10380286
    Abstract: The computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of one or more of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the one or more of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Grant
    Filed: February 20, 2017
    Date of Patent: August 13, 2019
    Assignee: International Business Machines Corporation
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Patent number: 10380289
    Abstract: Creating an integrated circuit with non-linear variations, the computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of one or more of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the one or more of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Grant
    Filed: November 27, 2017
    Date of Patent: August 13, 2019
    Assignee: International Business Machines Corporation
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Patent number: 10346569
    Abstract: Creating by a computer an integrated circuit with non-linear variations, the computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: July 9, 2019
    Assignee: International Business Machines Corporation
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Patent number: 10289776
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In accordance with aspects of the present disclosure, a computer-implemented method for statistical static timing analysis of an integrated circuit is provided. The method may comprise identifying a timing parameter that contributes to a delay calculation. The method may further comprise determining, by a processing device, whether the identified timing parameter significantly impacts the delay calculation. The method may also comprise, responsive to determining that the identified timing parameter does not significantly impact the delay calculation, avoiding a sensitivity calculation for the identified timing parameter.
    Type: Grant
    Filed: May 16, 2018
    Date of Patent: May 14, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Nathan Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Patent number: 10169526
    Abstract: An incremental parasitic extraction system includes a noise analysis module configured to perform a first noise analysis on at least one first net with respect to at least one aggressor net. The incremental parasitic extraction system further includes an optimizer module and an extraction module. The optimizer module performs a first optimization activity on the at least one first net based on results of the first noise analysis. The optimizer module further generates a first invalidation list based on the first optimization activity, and a second invalidation list based on a type of the first optimization action so as to add the second invalidation list to the first invalidation list. The extraction module processes the first and second invalidation lists and performs an extraction and noise analysis process on the first and second invalidation lists so as to determine at least one new RC network and associated noise analysis results.
    Type: Grant
    Filed: November 14, 2017
    Date of Patent: January 1, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kerim Kalafala, Tsz-Mei Ko, Ravichander Ledalla, Alice H. Lee, Adam P. Matheny, Jose L. Neves, Gregory M. Schaeffer
  • Publication number: 20180285503
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In accordance with aspects of the present disclosure, a computer-implemented method for statistical static timing analysis of an integrated circuit is provided. The method may comprise identifying a timing parameter that contributes to a delay calculation. The method may further comprise determining, by a processing device, whether the identified timing parameter significantly impacts the delay calculation. The method may also comprise, responsive to determining that the identified timing parameter does not significantly impact the delay calculation, avoiding a sensitivity calculation for the identified timing parameter.
    Type: Application
    Filed: May 16, 2018
    Publication date: October 4, 2018
    Inventors: Nathan Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Publication number: 20180239860
    Abstract: Creating an integrated circuit with non-linear variations, the computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of one or more of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the one or more of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Application
    Filed: December 22, 2017
    Publication date: August 23, 2018
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Publication number: 20180239859
    Abstract: Creating an integrated circuit with non-linear variations, the computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of one or more of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the one or more of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Application
    Filed: November 27, 2017
    Publication date: August 23, 2018
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Publication number: 20180239858
    Abstract: Creating an integrated circuit with non-linear variations, the computer identifies an integrated circuit design; identifies a timing model associated with the identified integrated circuit design; defines one or more static single sided variables; defines one or more regions of one or more of the defined one or more static single sided variables that are treated linearly; defines one or more multi-sided variables based on the defined one or more regions of the one or more of the defined one or more static single sided variables; identifies one or more timing paths within the identified integrated circuit design; performs a statistical static timing analysis on the identified timing model for the identified one or more timing paths within the identified integrated circuit design utilizing the defined one or more multi-sided variables; provides one or more timing quantities that project within a multi-parameter space based on the performed statistical static timing analysis.
    Type: Application
    Filed: February 20, 2017
    Publication date: August 23, 2018
    Inventors: Robert J. Allen, Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Debjit Sinha, Natesan Venkateswaran, Vladimir Zolotov
  • Publication number: 20180232476
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In one example according to aspects of the present disclosure, a computer-implemented method is provided. The method comprises performing an initial statistical static timing analysis of the integrated circuit to create a parameterized model of the integrated circuit for a plurality of paths using a plurality of timing corners to calculate a timing value for each of the plurality of paths, each of the plurality of timing corners representing a set of timing performance parameters. The method further comprises determining at least one worst timing corner from the parameterized model for each of the plurality of paths based on the initial statistical static timing analysis and calculated timing value for each of the plurality of paths. The method also comprises performing a subsequent analysis of the integrated circuit using the at least one worst timing corner.
    Type: Application
    Filed: April 12, 2018
    Publication date: August 16, 2018
    Inventors: Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Alexander J. Suess, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Patent number: 10031985
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In accordance with aspects of the present disclosure, a computer-implemented method for statistical static timing analysis of an integrated circuit is provided. The method may comprise identifying a timing parameter that contributes to a delay calculation. The method may further comprise determining, by a processing device, whether the identified timing parameter significantly impacts the delay calculation. The method may also comprise, responsive to determining that the identified timing parameter does not significantly impact the delay calculation, avoiding a sensitivity calculation for the identified timing parameter.
    Type: Grant
    Filed: January 8, 2016
    Date of Patent: July 24, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Nathan Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Patent number: 10013516
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In one example according to aspects of the present disclosure, a computer-implemented method is provided. The method comprises performing an initial statistical static timing analysis of the integrated circuit to create a parameterized model of the integrated circuit for a plurality of paths using a plurality of timing corners to calculate a timing value for each of the plurality of paths, each of the plurality of timing corners representing a set of timing performance parameters. The method further comprises determining at least one worst timing corner from the parameterized model for each of the plurality of paths based on the initial statistical static timing analysis and calculated timing value for each of the plurality of paths. The method also comprises performing a subsequent analysis of the integrated circuit using the at least one worst timing corner.
    Type: Grant
    Filed: October 24, 2016
    Date of Patent: July 3, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Alexander J. Suess, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Publication number: 20180068052
    Abstract: An incremental parasitic extraction system includes a noise analysis module configured to perform a first noise analysis on at least one first net with respect to at least one aggressor net. The incremental parasitic extraction system further includes an optimizer module and an extraction module. The optimizer module performs a first optimization activity on the at least one first net based on results of the first noise analysis. The optimizer module further generates a first invalidation list based on the first optimization activity, and a second invalidation list based on a type of the first optimization action so as to add the second invalidation list to the first invalidation list. The extraction module processes the first and second invalidation lists and performs an extraction and noise analysis process on the first and second invalidation lists so as to determine at least one new RC network and associated noise analysis results.
    Type: Application
    Filed: November 14, 2017
    Publication date: March 8, 2018
    Inventors: Kerim Kalafala, Tsz-Mei Ko, Ravichander Ledalla, Alice H. Lee, Adam P. Matheny, Jose L. Neves, Gregory M. Schaeffer
  • Patent number: 9858383
    Abstract: An incremental parasitic extraction system includes a noise analysis module configured to perform a first noise analysis on at least one first net with respect to at least one aggressor net. The incremental parasitic extraction system further includes an optimizer module and an extraction module. The optimizer module performs a first optimization activity on the at least one first net based on results of the first noise analysis. The optimizer module further generates a first invalidation list based on the first optimization activity, and a second invalidation list based on a type of the first optimization action so as to add the second invalidation list to the first invalidation list. The extraction module processes the first and second invalidation lists and performs an extraction and noise analysis process on the first and second invalidation lists so as to determine at least one new RC network and associated noise analysis results.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: January 2, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kerim Kalafala, Tsz-Mei Ko, Ravichander Ledalla, Alice H. Lee, Adam P. Matheny, Jose L. Neves, Gregory M. Schaeffer
  • Patent number: 9767239
    Abstract: System and methods for achieving a timing closure in a design of an integrated circuit in presence of manufacturing variation. The method includes running a timing engine of a statistical timing analysis tool performing at least one optimization to fix at least one violation of at least one timing quantity at an integrated circuit location. The method includes choosing at least one optimization to apply and finding at least one failing timing quantity, where the quantity is failing due to at least one source of variability which the optimization would impact. The optimization is applied to at least one section of the path leading to the failing timing quantity, where the section contributes to the source of variability. Statistical sensitivity information in canonical form guides the optimization by providing a fully parameterized canonical form of the identified timing violations.
    Type: Grant
    Filed: October 20, 2016
    Date of Patent: September 19, 2017
    Assignee: International Business Machines Corporation
    Inventors: Nathan C. Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Patent number: 9754062
    Abstract: A method of implementing timing adjustments across a transparent latch of an integrated circuit, a system, and a computer program product are described. The method includes obtaining initial input timing slack and input potential power savings at an input and an initial output timing slack and output potential power savings at an output of the transparent latch. The method also includes adjusting a cycle boundary of the transparent latch to obtain a new input timing slack at the input and a new output timing slack at the output of the transparent latch, wherein the new input timing slack is greater than the initial input timing slack based on the input potential power savings being greater than the output potential power savings and the new output timing slack is greater than the initial output timing slack based on the output potential power savings being greater than the input potential power savings.
    Type: Grant
    Filed: November 6, 2015
    Date of Patent: September 5, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Paul G. Villarrubia
  • Publication number: 20170199953
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In accordance with aspects of the present disclosure, a computer-implemented method for statistical static timing analysis of an integrated circuit is provided. The method may comprise identifying a timing parameter that contributes to a delay calculation. The method may further comprise determining, by a processing device, whether the identified timing parameter significantly impacts the delay calculation. The method may also comprise, responsive to determining that the identified timing parameter does not significantly impact the delay calculation, avoiding a sensitivity calculation for the identified timing parameter.
    Type: Application
    Filed: January 8, 2016
    Publication date: July 13, 2017
    Inventors: Nathan Buck, Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov
  • Publication number: 20170177784
    Abstract: An incremental parasitic extraction system includes a noise analysis module configured to perform a first noise analysis on at least one first net with respect to at least one aggressor net. The incremental parasitic extraction system further includes an optimizer module and an extraction module. The optimizer module performs a first optimization activity on the at least one first net based on results of the first noise analysis. The optimizer module further generates a first invalidation list based on the first optimization activity, and a second invalidation list based on a type of the first optimization action so as to add the second invalidation list to the first invalidation list. The extraction module processes the first and second invalidation lists and performs an extraction and noise analysis process on the first and second invalidation lists so as to determine at least one new RC network and associated noise analysis results.
    Type: Application
    Filed: December 18, 2015
    Publication date: June 22, 2017
    Inventors: Kerim Kalafala, Tsz-Mei Ko, Ravichander Ledalla, Alice H. Lee, Adam P. Matheny, Jose L. Neves, Gregory M. Schaeffer
  • Publication number: 20170161415
    Abstract: Examples of techniques for statistical static timing analysis of an integrated circuit are disclosed. In one example according to aspects of the present disclosure, a computer-implemented method is provided. The method comprises performing an initial statistical static timing analysis of the integrated circuit to create a parameterized model of the integrated circuit for a plurality of paths using a plurality of timing corners to calculate a timing value for each of the plurality of paths, each of the plurality of timing corners representing a set of timing performance parameters. The method further comprises determining at least one worst timing corner from the parameterized model for each of the plurality of paths based on the initial statistical static timing analysis and calculated timing value for each of the plurality of paths. The method also comprises performing a subsequent analysis of the integrated circuit using the at least one worst timing corner.
    Type: Application
    Filed: October 24, 2016
    Publication date: June 8, 2017
    Inventors: Eric A. Foreman, Jeffrey G. Hemmett, Kerim Kalafala, Gregory M. Schaeffer, Stephen G. Shuma, Alexander J. Suess, Natesan Venkateswaran, Chandramouli Visweswariah, Vladimir Zolotov