Patents by Inventor Samuel I. Ward

Samuel I. Ward 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: 8443313
    Abstract: A method comprises generating a first behavioral model of a circuit describing a physical circuit in a first configuration. The first configuration comprises a first master latch, a first fanout path, and a logic cone. The first master latch couples to the first fanout path and is configured to receive a first data input signal. The first fanout path comprises a plurality of output sinks, each coupled to the logic cone. The first behavioral model is modified to generate a second behavioral model describing the physical circuit in a second configuration. The second configuration comprises an error circuit and an abstract latch clone based on the first master latch. A configuration file is generated based on the second behavioral model. The configuration file comprises information representing a plurality of instantiated latch clones based on the abstract latch clone, each configured to couple to the first data input signal and to one or more output sinks of the plurality of output sinks.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: May 14, 2013
    Assignee: International Business Machines Corporation
    Inventors: Samuel I. Ward, Kevin F. Reick, Bryan J. Robbins, Thomas E. Rosser, Robert J. Shadowen
  • Publication number: 20130097573
    Abstract: An automated method for aligning a critical datapath in an integrated circuit design inserts an artificial alignment net in the netlist which interconnects all cells in the bit stack of the datapath. The cells are placed using a wirelength optimization which assigns weights to wire sections based on the alignment direction. The rate of change of the alignment weighting value can vary during different stages of global placement. The invention is particularly suited for a force-directed placer which uses a linear system solver to obtain a globally optimum solution for placement of the cells having some overlap among the cells, and thereafter spreads the cells to reduce the overlap. Pseudo nets are also inserted which interconnect a cell and an expected location of the cell after spreading for that iteration.
    Type: Application
    Filed: October 17, 2011
    Publication date: April 18, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Myung-Chul Kim, Natarajan Viswanathan, Samuel I. Ward
  • Patent number: 8386230
    Abstract: A method includes generating a first behavioral model of a circuit, the first behavioral model describing a physical circuit in a first configuration. The first configuration comprises a first logic structure configured to generate a first intermediate signal based on a received first plurality of inputs. The first configuration further comprises a logic cone configured to generate a scan output based on the first intermediate signal and a plurality of scan inputs. The first behavioral model is modified to generate a second behavioral model describing the physical circuit in a second configuration. The second configuration comprises an error circuit configured to receive the scan output and the first intermediate signal. A testability model is generated based on the second behavioral model, the testability model comprising a first structural representation of the first logic structure.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: February 26, 2013
    Assignee: International Business Machines Corporation
    Inventors: Samuel I. Ward, Kevin F. Reick, Bryan J. Robbins, Thomas E. Rosser, Robert J. Shadowen
  • Patent number: 8365075
    Abstract: Systems, methods and articles of manufacture are disclosed for recording events occurring in a virtual world. In one embodiment, properties of events previously recorded and/or attended by a user may be identified. Recording criteria for the user may be derived from the identified properties. Upon identifying an event satisfying the recording criteria, the event may be recorded. The recorded event may be played back at the convenience of the user.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: January 29, 2013
    Assignee: International Business Machines Corporation
    Inventors: Kulvir S. Bhogal, Lisa Seacat DeLuca, Timothy J. Eby, Samuel I. Ward
  • Publication number: 20130014011
    Abstract: Systems, methods and articles of manufacture are disclosed for recording events occurring in a virtual world. In one embodiment, properties of events previously recorded and/or attended by a user may be identified. Recording criteria for the user may be derived from the identified properties. Upon identifying an event satisfying the recording criteria, the event may be recorded. The recorded event may be played back at the convenience of the user.
    Type: Application
    Filed: September 15, 2012
    Publication date: January 10, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kulvir S. Bhogal, Lisa Seacat DeLuca, Timothy J. Eby, Samuel I. Ward
  • Publication number: 20120284676
    Abstract: Decoupling capacitors (dcaps) are placed in an IC design by assigning different dcap utilization rates to logic cones, applying the rates to corresponding dcap regions surrounding cells in the cones, identifying any overlap of regions from different logic cones, and inserting a dcap at the overlapping region having the highest dcap utilization rate. The best location for the dcap is computed using a hypergraph wherein the cells are edges and the regions are nodes. Any node that is dominated by another node is removed and its edge is extended to the dominating node. The dcap is inserted in the region having the most edges (the edges can be weighted). The process is repeated iteratively, updating the hypergraph by removing nodes connected to dcap location, and inserting the next dcap at a region corresponding to the node which then has the greatest number of connected edges.
    Type: Application
    Filed: May 3, 2011
    Publication date: November 8, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jeremy T. Hopkins, Samuel I. Ward, David A. Papa
  • Publication number: 20120266124
    Abstract: Mechanisms are provided for performing placement of cells in a design of a semiconductor device. An initial design of the semiconductor device is generated, the initial design comprising a first placement of cells. A preferred direction of placement associated with the cells is determined. The preferred direction is a direction along which spreading of the cells is preferred. A second design of the semiconductor device is generated by modifying the first placement of the cells to generate a second placement of cells, different from the first placement cells, based on the preferred direction of placement associated with the cells.
    Type: Application
    Filed: April 14, 2011
    Publication date: October 18, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Charles J. Alpert, Myung-Chul Kim, Zhuo Li, Natarajan Viswanathan, Samuel I. Ward
  • Patent number: 8266566
    Abstract: Spare cells are placed in an IC design using stability values associated with logic cones of the design. A desired spare cell utilization rate is assigned to a cone based on its stability value, and an actual spare cell utilization rate for the cone bounding box is calculated. If the actual utilization rate is less than the desired utilization rate, additional spare cells are inserted as needed to attain the desired utilization rate. The stability value is provided by a logic or circuit designer, or derived from historical information regarding the logic cone in a previous design iteration. Spare cells are placed for each logic cone in the design until a global spare cell utilization target is exceeded. The spare cell placement method can be an integrated part of a placement directed synthesis which is followed by early mode padding and design routing.
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: September 11, 2012
    Assignee: International Business Machines Corporation
    Inventors: Jeremy T. Hopkins, Julie A. Rosser, Samuel I. Ward
  • Patent number: 8239430
    Abstract: Performing a calculation using a coordinate rotation digital computer (CORDIC) algorithm. Execution of the CORDIC algorithm is begun. An error introduced by a truncated vector as a result of executing the CORDIC algorithm is pre-computed. The error is incorporated into a subsequent iteration of the CORDIC algorithm. Execution of the CORDIC algorithm is completed. The result of the CORDIC algorithm is stored.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: August 7, 2012
    Assignee: International Business Machines Corporation
    Inventors: David N. Ault, Emiliano Lozano, Bao G. Truong, Samuel I. Ward
  • Patent number: 8234612
    Abstract: Spare cells are placed in an IC design by assigning different spare utilization rates to logic cones, applying the rates to corresponding spare cell regions surrounding cells in the cones, identifying any overlap of regions from different logic cones, and inserting a spare cell at the overlapping region having the highest spare utilization rate. The best location for the spare cell is computed using a hypergraph wherein the cells are edges and the regions are nodes. Any node that is dominated by another node is removed and its edge is extended to the dominating node. The spare cell is inserted in the region having the most edges (the edges can be weighted). The process is repeated iteratively, updating the hypergraph by removing nodes connected to spare cell location, and inserting the next spare cell at a region corresponding to the node which then has the greatest number of connected edges.
    Type: Grant
    Filed: August 25, 2010
    Date of Patent: July 31, 2012
    Assignee: International Business Machines Corporation
    Inventors: Benjiman L. Goodman, Nathaniel D. Hieter, Jeremy T. Hopkins, Samuel I. Ward
  • Patent number: 8214170
    Abstract: A method for test pattern compression generates a first test pattern comprising a plurality of bits. The method identifies bits comprising a don't-care bit value in the first test pattern and replaces the identified bit values with random bit values, to generate a second test pattern. The method determines a fault coverage level of the second test pattern. In the event the determined fault coverage level of the second test pattern exceeds a predetermined individual test pattern fault coverage level, for at least one bit position in the second test pattern corresponding to a replaced identified bit value and detecting at least one fault, the method exchanges the don't care value in the bit position in the first test pattern with the bit value in the corresponding bit position in the second test pattern. The method merges subsequent test patterns that increase fault coverage with the second test pattern.
    Type: Grant
    Filed: January 15, 2009
    Date of Patent: July 3, 2012
    Assignee: International Business Machines Corporation
    Inventors: Patrick R. Crosby, Daniel W. Cervantes, Johnny J. LeBlanc, Samuel I. Ward
  • Patent number: 8140903
    Abstract: A method for tracing thread bus transactions in a multiprocessor system comprises decoding, by a processor, a first thread instruction of a thread, the thread comprising an ordered series of thread instructions. In the event the first thread instruction is a set bus trace enable bit (BTEB) instruction, the processor sets a bus trace enable bit corresponding to the thread. In the event the BTEB is set, the processor determines whether the first thread instruction is a trace-eligible instruction and, in the event the first thread instruction is a trace-eligible instruction, and the BTEB is set, the processor sets a snoop tag trace enable bit (STTEB). A hardware trace monitor (HTM) monitors bus transactions, each bus transaction comprising a STTE. In the event a monitored bus transaction comprises a set STTEB, the HTM stores the bus transaction as trace data. In the event a monitored bus transaction comprises a reset STTEB, the HTM does not store the bus transaction as trace data.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: March 20, 2012
    Assignee: International Business Machines Corporation
    Inventors: Benjiman L. Goodman, Sertac Cakici, Samuel I. Ward, Linton B. Ward, Jr.
  • Publication number: 20120066654
    Abstract: Spare cells are placed in an IC design using stability values associated with logic cones of the design. A desired spare cell utilization rate is assigned to a cone based on its stability value, and an actual spare cell utilization rate for the cone bounding box is calculated. If the actual utilization rate is less than the desired utilization rate, additional spare cells are inserted as needed to attain the desired utilization rate. The stability value is provided by a logic or circuit designer, or derived from historical information regarding the logic cone in a previous design iteration. Spare cells are placed for each logic cone in the design until a global spare cell utilization target is exceeded. The spare cell placement method can be an integrated part of a placement directed synthesis which is followed by early mode padding and design routing.
    Type: Application
    Filed: September 10, 2010
    Publication date: March 15, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jeremy T. Hopkins, Julie A. Rosser, Samuel I. Ward
  • Publication number: 20120054707
    Abstract: Spare cells are placed in an IC design by assigning different spare utilization rates to logic cones, applying the rates to corresponding spare cell regions surrounding cells in the cones, identifying any overlap of regions from different logic cones, and inserting a spare cell at the overlapping region having the highest spare utilization rate. The best location for the spare cell is computed using a hypergraph wherein the cells are edges and the regions are nodes. Any node that is dominated by another node is removed and its edge is extended to the dominating node. The spare cell is inserted in the region having the most edges (the edges can be weighted). The process is repeated iteratively, updating the hypergraph by removing nodes connected to spare cell location, and inserting the next spare cell at a region corresponding to the node which then has the greatest number of connected edges.
    Type: Application
    Filed: August 25, 2010
    Publication date: March 1, 2012
    Applicant: International Business Machines Corporation
    Inventors: Benjiman L. Goodman, Nathaniel D. Hieter, Jeremy T. Hopkins, Samuel I. Ward
  • Publication number: 20120047476
    Abstract: A method comprises generating a first behavioral model of a circuit describing a physical circuit in a first configuration. The first configuration comprises a first master latch, a first fanout path, and a logic cone. The first master latch couples to the first fanout path and is configured to receive a first data input signal. The first fanout path comprises a plurality of output sinks, each coupled to the logic cone. The first behavioral model is modified to generate a second behavioral model describing the physical circuit in a second configuration. The second configuration comprises an error circuit and an abstract latch clone based on the first master latch. A configuration file is generated based on the second behavioral model. The configuration file comprises information representing a plurality of instantiated latch clones based on the abstract latch clone, each configured to couple to the first data input signal and to one or more output sinks of the plurality of output sinks.
    Type: Application
    Filed: August 18, 2010
    Publication date: February 23, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Samuel I. Ward, Kevin F. Reick, Bryan J. Robbins, Thomas E. Rosser, Robert J. Shadowen
  • Publication number: 20120046921
    Abstract: A method includes generating a first behavioral model of a circuit, the first behavioral model describing a physical circuit in a first configuration. The first configuration comprises a first logic structure configured to generate a first intermediate signal based on a received first plurality of inputs. The first configuration further comprises a logic cone configured to generate a scan output based on the first intermediate signal and a plurality of scan inputs. The first behavioral model is modified to generate a second behavioral model describing the physical circuit in a second configuration. The second configuration comprises an error circuit configured to receive the scan output and the first intermediate signal. A testability model is generated based on the second behavioral model, the testability model comprising a first structural representation of the first logic structure.
    Type: Application
    Filed: August 18, 2010
    Publication date: February 23, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Samuel I. Ward, Kevin F. Reick, Bryan J. Robbins, Thomas E. Rosser, Robert J. Shadowen
  • Patent number: 8028266
    Abstract: A method for automatically generating an electronic circuit layout with placed circuit elements includes receiving a user provided schematic, the user provided schematic comprising a plurality of circuit elements, each circuit element comprising general parameters. The method associates a plurality of first placement parameters with each of the plurality of circuit elements. The method retrieves, from a design library, design parameters associated with at least one of the plurality of circuit elements. The method selects a subset of circuit elements and receives placement inputs. The method generates a first placed layout configuration comprising adjusted placement parameters, based on the received placement inputs, the first placement parameters, and the design parameters. The method assigns absolute placement coordinates for each of the plurality of circuit elements based on the first placed layout configuration.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: September 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: William D. Ramsour, Samuel I. Ward
  • Patent number: 8028265
    Abstract: A method for generating an electronic circuit layout with placed circuit elements receives a user provided schematic, the user provided schematic comprising a plurality of circuit elements, each circuit element comprising general parameters. The method associates a plurality of first placement parameters with each of the plurality of circuit elements, wherein the first placement parameters comprise a cell horizontal position, a cell vertical stacking position, and a cell vertical adjacent spacing. The method retrieves, from a design library, design parameters associated with at least one of the plurality of circuit elements. The method assigns first absolute placement coordinates for each of the plurality of circuit elements based on the first placement parameters and the design parameters. The method defines and performs an adjustment operation on the placement parameters of a selected subset of circuit elements, generating adjusted placement parameters.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: September 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: William D. Ramsour, Samuel I. Ward, Jun Zhou
  • Patent number: 8014215
    Abstract: A mechanism is provided for gating a read access of any row in a cache access memory that has been invalidated. An address decoder in the cache access memory sends a memory access to a non-gated wordline driver and a gated wordline driver associated with the memory access. The non-gated wordline driver outputs the data stored in a valid bit memory cell to the gated wordline driver in response to the non-gated wordline driver determining the memory access as a read access. The gated wordline driver determines whether the data from the valid bit memory cell from the non-gated wordline driver indicates either valid data or invalid data in response to the gated wordline driver determining the memory access as a read access and denies an output of the data in a row of memory cells associated with the gated wordline driver in response to the data being invalid.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: September 6, 2011
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Lee, Bao G. Truong, Samuel I. Ward
  • Patent number: 8006152
    Abstract: A method comprises generating a test pattern for a device under test (DUT), wherein the DUT comprises a plurality of scan chains coupled to a plurality of multiple input shift registers (MISRs). The plurality of faults detected by a first MISR and by a second MISR are identified. In the event the plurality of faults detected by the first MISR does not include any of the plurality of faults detected by the second MISR and the plurality of faults detected by the second MISR does not include any of the plurality of faults detected by the first MISR, the first MISR and the second MISR are coupled as an independent MISR pair. The test pattern is applied to the DUT to generate a scan chain output. The independent MISR pair captures the scan chain output to generate a test signature. The test signature is compared with a known good signature.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: August 23, 2011
    Assignee: International Business Machines Corporation
    Inventors: Samuel I. Ward, Patrick R. Crosby, William D. Ramsour, Bao G. Truong