Patents by Inventor Shervin Hojat

Shervin Hojat 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: 7216316
    Abstract: Broadly speaking, a method is provided for evaluating nets in a crosstalk noise analysis. More specifically, a method is provided for evaluating timing window overlap between a pair of nets. The method includes selecting one timing window from each net of the pair of nets for analysis. The method further includes analyzing characteristics of the timing windows selected from the pair of nets to identify a timing window overlap presence, wherein the timing window overlap presence can exist between any two timing windows associated with each net of the pair of nets, respectively.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: May 8, 2007
    Assignee: Sun Microsystems, Inc.
    Inventors: Jeannette N. Sutherland, Robert E. Mains, Matthew J. Amatangelo, Shervin Hojat
  • Patent number: 6944811
    Abstract: A blockage aware zero skew clock routing method for calculating the distance, and therefore the delay, between two points takes into account any blockages along the path between the two points and therefore creates a more usable and realistic measure of delay and allows for minimization, or elimination, of clock skew in the system being designed using the method of the invention.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: September 13, 2005
    Assignee: Sun Microsystems, Inc.
    Inventor: Shervin Hojat
  • Patent number: 6819138
    Abstract: Devices, methods, and networks that divide and proportionally distribute the drive strength of a clock buffer such that the output drive strength of the clock buffer is divided proportionally among a plurality of outputs from the clock buffer. In one embodiment, the present invention selectively couples adjacent parallel inverters present in a clock buffer to separate, internal distribution wires. The internal distribution wires are selectively coupled to one or more outputs by a connector wire to provide proportional, multiple outputs of the drive strength from the clock buffer to a clock network.
    Type: Grant
    Filed: November 4, 2002
    Date of Patent: November 16, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: David Hogenmiller, Harsh Sharma, Shervin Hojat
  • Patent number: 6789245
    Abstract: Coupling capacitance is used to balance skew in a network. In one embodiment, the coupling capacitance exerted by shielding wires oppositely adjacent one or more signal wires in a network is utilized to vary the speed of a signal carried on the one or more signal wires to balance skew in the network.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: September 7, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: Shervin Hojat, David Hogenmiller, Harsh Sharma
  • Publication number: 20040085094
    Abstract: Devices, methods, and networks that divide and proportionally distribute the drive strength of a clock buffer such that the output drive strength of the clock buffer is divided proportionally among a plurality of outputs from the clock buffer. In one embodiment, the present invention selectively couples adjacent parallel inverters present in a clock buffer, to separate, internal distribution wires. The internal distribution wires are selectively coupled to one or more outputs by a connector wire to provide proportional, multiple outputs of the drive strength from the clock buffer to a clock network.
    Type: Application
    Filed: November 4, 2002
    Publication date: May 6, 2004
    Applicant: Sun Microsystems, Inc.
    Inventors: David Hogenmiller, Harsh Sharma, Shervin Hojat
  • Publication number: 20040078773
    Abstract: Predetermined and standardized path templates are introduced between points and/or elements in an integrated circuit layout. According to one embodiment of the invention, the standardized path templates are made up of two or more parallel tracks of path segments, with or without corresponding perpendicular path segments. According to the invention, the path segments are connected as needed to form serpentine or non-serpentine paths of the required length.
    Type: Application
    Filed: October 21, 2002
    Publication date: April 22, 2004
    Applicant: Sun Microsystems, Inc.
    Inventors: Harsh Sharma, Shervin Hojat, David Hogenmiller
  • Publication number: 20040068709
    Abstract: Coupling capacitance is used to balance skew in a network. In one embodiment, the coupling capacitance exerted by shielding wires oppositely adjacent one or more signal wires in a network is utilized to vary the speed of a signal carried on the one or more signal wires to balance skew in the network.
    Type: Application
    Filed: October 8, 2002
    Publication date: April 8, 2004
    Applicant: Sun Microsystems, Inc.
    Inventors: Shervin Hojat, David Hogenmiller, Harsh Sharma
  • Publication number: 20040059969
    Abstract: A blockage aware zero skew clock routing method for calculating the distance, and therefore the delay, between two points takes into account any blockages along the path between the two points and therefore creates a more usable and realistic measure of delay and allows for minimization, or elimination, of clock skew in the system being designed using the method of the invention.
    Type: Application
    Filed: August 7, 2002
    Publication date: March 25, 2004
    Applicant: Sun Microsystems, Inc.
    Inventor: Shervin Hojat
  • Patent number: 6080201
    Abstract: One aspect of the invention relates to a method for improving timing convergence in computer aided semiconductor circuit design. In one particular version of the invention, the method includes the steps of generating a behavioral model of a desired semiconductor circuit, which includes timing constraints for individual paths in the circuit, synthesizing the behavioral model to produce a netlist which represents an implementation of the desired semiconductor circuit mapped to a specific semiconductor technology, the netlist including a list of components in the circuit and a list of nets which connect the components in the circuit, and the step of synthesizing includes performing a timing analysis on the implementation so that the paths in the circuit represented by the netlist meet the timing constraints, the timing analysis being performed using estimated wire lengths for the nets. Next, the components in the netlist are placed into an image representing a predefined area of the semiconductor chip.
    Type: Grant
    Filed: February 10, 1998
    Date of Patent: June 27, 2000
    Assignee: International Business Machines Corporation
    Inventors: Shervin Hojat, Paul Gerard Villarrubia