Patents by Inventor Nishath Verghese

Nishath Verghese 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: 8225248
    Abstract: DFM systems are provided that incorporate manufacturing variations in the analysis of integrated circuits by calculating predicted manufacturing variations on the shapes of interconnects and devices of the drawn layout of a circuit design. The shape variation on interconnects is converted to variations in resistor-capacitor (RC) parasitics. The shape variation on devices is converted to variations in device parameters. The variation in device parameters and wire parasitics is converted to changes in timing performance, signal integrity, and power consumption by determining the impact of device parameter and wire parasitic variations on the behavior of each instance of a standard cell. The results from these analyses are integrated back into the design flow as incremental delay files (timing), noise failures and buffer insertion/driver resizing commands (noise), and leakage power hotspots and cell substitution commands (power consumption).
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: July 17, 2012
    Assignee: Cadence Design Systems, Inc.
    Inventors: Haizhou Chen, Li-Fu Chang, Richard Rouse, Nishath Verghese
  • Patent number: 7844438
    Abstract: A method to analyze and correct dynamic power grid variations in an IC includes performing a dynamic power grid analysis of the circuit, identifying an excessive dynamic power grid voltage fluctuation from the analysis, and modifying the circuit to reduce the excessive dynamic power grid fluctuation.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: November 30, 2010
    Assignee: Cadence Design Systems, Inc.
    Inventors: Nishath Verghese, Kenneth Tseng
  • Patent number: 7673260
    Abstract: DFM systems are provided that incorporate manufacturing variations in the analysis of integrated circuits by calculating predicted manufacturing variations on the shapes of interconnects and devices of the drawn layout of a circuit design. The shape variation on interconnects is converted to variations in resistor-capacitor (RC) parasitics. The shape variation on devices is converted to variations in device parameters. The variation in device parameters and wire parasitics is converted to changes in timing performance, signal integrity, and power consumption by determining the impact of device parameter and wire parasitic variations on the behavior of each instance of a standard cell. The results from these analyses are integrated back into the design flow as incremental delay files (timing), noise failures and buffer insertion/driver resizing commands (noise), and leakage power hotspots and cell substitution commands (power consumption).
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: March 2, 2010
    Assignee: Cadence Design Systems, Inc.
    Inventors: Haizhou Chen, Li-Fu Chang, Richard Rouse, Nishath Verghese
  • Patent number: 7359843
    Abstract: A method of delay change determination in an integrated circuit design including a stage with a victim net and one or more aggressor nets capacitively coupled thereto, the method comprising: determining a nominal (noiseless) victim net signal transition; determining a noisy victim net signal transition; and determining a delay change based upon nominal and noisy victim signal transition arrival times at a victim net receiver output.
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: April 15, 2008
    Assignee: Cadence Design Systems, Inc.
    Inventors: Igor Keller, Kenneth Tseng, Nishath Verghese
  • Publication number: 20070099314
    Abstract: DFM systems are provided that incorporate manufacturing variations in the analysis of integrated circuits by calculating predicted manufacturing variations on the shapes of interconnects and devices of the drawn layout of a circuit design. The shape variation on interconnects is converted to variations in resistor-capacitor (RC) parasitics. The shape variation on devices is converted to variations in device parameters. The variation in device parameters and wire parasitics is converted to changes in timing performance, signal integrity, and power consumption by determining the impact of device parameter and wire parasitic variations on the behavior of each instance of a standard cell. The results from these analyses are integrated back into the design flow as incremental delay files (timing), noise failures and buffer insertion/driver resizing commands (noise), and leakage power hotspots and cell substitution commands (power consumption).
    Type: Application
    Filed: October 24, 2006
    Publication date: May 3, 2007
    Inventors: Haizhou Chen, Li-Fu Chang, Richard Rouse, Nishath Verghese
  • Publication number: 20070094623
    Abstract: DFM systems are provided that incorporate manufacturing variations in the analysis of integrated circuits by calculating predicted manufacturing variations on the shapes of interconnects and devices of the drawn layout of a circuit design. The shape variation on interconnects is converted to variations in resistor-capacitor (RC) parasitics. The shape variation on devices is converted to variations in device parameters. The variation in device parameters and wire parasitics is converted to changes in timing performance, signal integrity, and power consumption by determining the impact of device parameter and wire parasitic variations on the behavior of each instance of a standard cell. The results from these analyses are integrated back into the design flow as incremental delay files (timing), noise failures and buffer insertion/driver resizing commands (noise), and leakage power hotspots and cell substitution commands (power consumption).
    Type: Application
    Filed: October 24, 2006
    Publication date: April 26, 2007
    Inventors: Haizhou Chen, Li-Fu Chang, Richard Rouse, Nishath Verghese
  • Publication number: 20050278671
    Abstract: A system, method, and computer program accurately models circuit parameter variation for delay calculation. For any given circuit parameter value, a cell is characterized at just three values in the circuit parameter range. An interpolation process generates an equation to calculate delay using the characterization data from the three circuit parameter values. This delay equation calculates the delay for any value in the circuit parameter range. Similar methodology is used to model simultaneous variation of two circuit parameters. The cell is characterized at just six circuit parameter pairs to interpolate the delay equation for any circuit parameter pair in the characterized ranges. This methodology can be extended to accommodate variation of multiple circuit parameters using similar interpolation techniques.
    Type: Application
    Filed: December 15, 2004
    Publication date: December 15, 2005
    Applicant: Cadence Design Systems, Inc.
    Inventors: Nishath Verghese, Hong Zhao