Patents by Inventor Steven E. Charlebois

Steven E. Charlebois 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: 7886253
    Abstract: A design structure that performs iterative synthesis of an integrated circuit design to attain power closure is described. In one embodiment, the design structure is embodied in a computer readable medium and has the capability to initially synthesized an integrated circuit design to satisfy timing and power constraints. Results from the initial synthesis are fed back into the synthesis process where specific nodes in the circuit design are targeted to satisfy the timing and power constraints. Selected nodes in the circuit design are worked on in an iterative manner until it has been determined that all of selected nodes have undergone evaluation for satisfying timing and power constraints. Once all of the selected nodes have undergone evaluation for satisfying timing and power constraints, then a final netlist representing the circuit design is generated.
    Type: Grant
    Filed: October 16, 2007
    Date of Patent: February 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Patent number: 7873923
    Abstract: Power gating logic cones is described. In one embodiment a method includes synthesizing logic for an integrated circuit (IC) design; identifying low switching nodes within the logic that switch less than a threshold; determining a potential power gating cone (PGC) based on the identified low switching nodes; determining a power gating logic expression for the potential PGC that includes a minimum set of inputs to the potential PGC that are least switching; determining whether energy savings using the power gating logic expression meets a criteria; and accepting the potential PGC in response to meeting the criteria.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: January 18, 2011
    Assignee: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Publication number: 20090222772
    Abstract: Power gating logic cones is described. In one embodiment a method includes synthesizing logic for an integrated circuit (IC) design; identifying low switching nodes within the logic that switch less than a threshold; determining a potential power gating cone (PGC) based on the identified low switching nodes; determining a power gating logic expression for the potential PGC that includes a minimum set of inputs to the potential PGC that are least switching; determining whether energy savings using the power gating logic expression meets a criteria; and accepting the potential PGC in response to meeting the criteria.
    Type: Application
    Filed: February 28, 2008
    Publication date: September 3, 2009
    Inventors: Steven E Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Patent number: 7539968
    Abstract: An approach that iteratively synthesizes an integrated circuit design to attain power closure is described. In one embodiment, the integrated circuit design is initially synthesized to satisfy timing and power constraints. Results from the initial synthesis are fed back into the synthesis process where specific nodes in the circuit design are targeted to satisfy the timing and power constraints. Selected nodes in the circuit design are worked on in an iterative manner until it has been determined that all of selected nodes have undergone evaluation for satisfying timing and power constraints. Once all of the selected nodes have undergone evaluation for satisfying timing and power constraints, then a final netlist representing the circuit design is generated.
    Type: Grant
    Filed: June 7, 2007
    Date of Patent: May 26, 2009
    Assignee: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Publication number: 20090100398
    Abstract: A design structure that performs iterative synthesis of an integrated circuit design to attain power closure is described. In one embodiment, the design structure is embodied in a computer readable medium and has the capability to initially synthesized an integrated circuit design to satisfy timing and power constraints. Results from the initial synthesis are fed back into the synthesis process where specific nodes in the circuit design are targeted to satisfy the timing and power constraints. Selected nodes in the circuit design are worked on in an iterative manner until it has been determined that all of selected nodes have undergone evaluation for satisfying timing and power constraints. Once all of the selected nodes have undergone evaluation for satisfying timing and power constraints, then a final netlist representing the circuit design is generated.
    Type: Application
    Filed: October 16, 2007
    Publication date: April 16, 2009
    Applicant: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Publication number: 20080307383
    Abstract: An approach that iteratively synthesizes an integrated circuit design to attain power closure is described. In one embodiment, the integrated circuit design is initially synthesized to satisfy timing and power constraints. Results from the initial synthesis are fed back into the synthesis process where specific nodes in the circuit design are targeted to satisfy the timing and power constraints. Selected nodes in the circuit design are worked on in an iterative manner until it has been determined that all of selected nodes have undergone evaluation for satisfying timing and power constraints. Once all of the selected nodes have undergone evaluation for satisfying timing and power constraints, then a final netlist representing the circuit design is generated.
    Type: Application
    Filed: June 7, 2007
    Publication date: December 11, 2008
    Applicant: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul D. Kartschoke, John J. Reilly, Manikandan Viswanath
  • Patent number: 7444609
    Abstract: A system and method for optimizing customizable filler cells in an integrated circuit physical design process. In particular, a filler cell placement algorithm of the present disclosure is utilized in the method to optimize the customizable filler cells in a circuit layout. The filler cell placement algorithm performs the operation of selecting a starting point within a given circuit layout, selecting a direction in which the position of logic cells is adjusted, adjusting the position of logic cells and, thereby, combining filler cells in order to increase the accumulated area thereof; suspending the adjustment operation when a customizable filler cell is formed; and resuming the adjustment operation from the point of the newly formed customizable filler cell. Additionally, a method of optimizing the locations, number, and distribution of the customizable filler cells in an integrated circuit design by use of the filler cell placement algorithm is provided.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: October 28, 2008
    Assignee: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Paul E. Dunn, George W. Rohrbaugh, III
  • Publication number: 20080005712
    Abstract: A system and method for optimizing customizable filler cells in an integrated circuit physical design process. In particular, a filler cell placement algorithm of the present disclosure is utilized in the method to optimize the customizable filler cells in a circuit layout. The filler cell placement algorithm performs the operation of selecting a starting point within a given circuit layout, selecting a direction in which the position of logic cells is adjusted, adjusting the position of logic cells and, thereby, combining filler cells in order to increase the accumulated area thereof; suspending the adjustment operation when a customizable filler cell is formed; and resuming the adjustment operation from the point of the newly formed customizable filler cell. Additionally, a method of optimizing the locations, number, and distribution of the customizable filler cells in an integrated circuit design by use of the filler cell placement algorithm is provided.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 3, 2008
    Inventors: Steven E. Charlebois, Paul E. Dunn, George W. Rohrbaugh
  • Patent number: 7194715
    Abstract: A method for performing static timing analysis on digital electronic circuits is disclosed. A snip (or DC adjust) file is initially generated. Static timing analysis is then performed on the final circuit netlist using the snip file. If the final circuit netlist meets all the timing constraints, the snip file is converted to a group of cutpoints, and formal verification is performed on the cutpoints. A determination is made as to whether or not the cutpoints pass formal verification. If the cutpoints pass formal verification, the user analysis on the final circuit netlist is completed, and the final circuit netlist can proceed to manufacturing. Otherwise, if the cutpoints do not pass formal verification, a flag is issued to alert a user. The user then has to either modify certain snip point(s) within the snip file or modify the circuit netlist, and perform the user analysis again.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: March 20, 2007
    Assignee: International Business Machines Corporation
    Inventors: Steven E. Charlebois, Gerard M. Salem