Patents by Inventor John G. Rohrbaugh

John G. Rohrbaugh 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: 7516379
    Abstract: A circuit and method for determining operating speed of a clock associated with an integrated circuit (IC), includes an IC logic element, a scan chain, and a calibration circuit including a first plurality of flip-flops and a combinational delay line. The calibration circuit operates in a functional test mode and in a scan test mode to determine a clock signal delay between the functional test mode and the scan test mode.
    Type: Grant
    Filed: April 6, 2004
    Date of Patent: April 7, 2009
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: John G. Rohrbaugh, Jeffrey R. Rearick
  • Patent number: 7139955
    Abstract: Hierarchically-controlled automatic test pattern generation (ATPG) is provided. One embodiment comprises a method for automatically generating test patterns for testing a device under test. Briefly described, one such method comprises the steps of: receiving a hierarchical model of a device under test, the hierarchical model comprising at least one low-level design component and at least one high-level design component which contains the low-level design component; selecting a fault to be detected in the device under test; and performing an automatic test pattern generation (ATPG) algorithm on the design components based on the hierarchy of the hierarchical model.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: November 21, 2006
    Assignee: Avago Technologies General IP (singapore) Pte. Ltd.
    Inventors: John G Rohrbaugh, Jeff Rearick
  • Patent number: 7043674
    Abstract: Methods for testing integrated circuits (ICs) are provided. An embodiment of a method comprises: electrically interconnecting automated test equipment (ATE) with the IC; providing at least one stimulus such that the IC determines the presence of a leakage current of the first pad; and receiving information corresponding to the leakage current of the first pad. Systems also are provided.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: May 9, 2006
    Inventors: Jeffrey R. Rearick, John G. Rohrbaugh, Shad Shepston
  • Patent number: 6986085
    Abstract: Integrated circuits (ICs) are provided. A representative IC includes a first pad electrically communicating with at least a portion of the IC. The first pad includes a first driver and a first receiver, with the first driver being configured to provide a first pad output signal to a component external to the IC, and the first receiver being configured to receive a first pad input signal from a component external to the IC. The first receiver also is configured to provide, to a component internal to the IC, a first receiver digital output signal in response to the first pad input signal. A first test circuit also is provided that is internal to the IC. The first test circuit is adapted to provide information corresponding to the driver tristate leakage current of the first pad. Methods, computer-readable media, systems and other ICs also are provided.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: January 10, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: Jeffrey R. Rearick, John G. Rohrbaugh, Shad Shepston
  • Patent number: 6944837
    Abstract: A system and method for evaluating a device under test (DUT) that utilizes a model of the DUT interfaced to DUT interface logic, which is designed to interface the DUT to automated testing equipment (ATE). By ensuring that the model includes a description of the DUT and of the DUT testing interface, conditions such as connections between ports of the IC (i.e., buddying) that may or may not be interfaced to the ATE may be included in the model to enable precise test pattern sets to be generated using the model. The test pattern sets may be used by a simulator to test the design of an IC or by ATE to test a fabricated IC having the design.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: September 13, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: John G Rohrbaugh, Jeff Rearick, Christopher M Juenemann
  • Patent number: 6907376
    Abstract: A preferred integrated circuit for facilitating receiver trip level testing functionality includes a first pad which incorporates a first driver and a first receiver. The first driver is configured to provide a first pad output signal to a component external to the IC. The first receiver is configured to receive a first pad input signal from a component external to the IC, and to provide a first receiver digital output signal to a component internal to the IC in response to the first pad input signal. Additionally, a first test circuit is provided that is arranged internal to the IC, with the first test circuit being adapted to provide information corresponding to at least one receiver trip-level characteristic of the first receiver of the first pad. Systems, methods and computer readable media also are provided.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: June 14, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: Shad R. Shepston, Jeffrey R. Rearick, John G. Rohrbaugh
  • Patent number: 6895562
    Abstract: A method and apparatus of carrying out a computer assisted analysis function on a hierarchical circuit model. The method is carried out by inputting the hierarchical circuit model, specifying at least one circuit block within the hierarchy as a target of the function on the target block, and simplifying the hierarchical circuit model by deleting circuit blocks not affecting the analysis function, to produce a simplified hierarchical circuit model. A computer assisted analysis function can then be carried out on the simplified hierarchical circuit model.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: May 17, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: John G Rohrbaugh, Jeff Rearick, Daryl H Allred
  • Patent number: 6865706
    Abstract: The present invention is generally directed to an improved automatic test pattern generator for generating test patterns that are used by an integrated circuit testing device. In accordance with one aspect of the invention, a method is provided for generating a set of test vectors for testing an integrated circuit, each test vector of the set of test vectors containing a plurality of bits defining test inputs for the integrated circuit. The method includes the steps of defining a list of faults for the integrated circuit, and generating at least one test vector that defines values for those inputs necessary to detect at least one target fault selected from the list of faults, the values comprising only a portion of the bits of the at least one test vector, wherein a remainder of the bits in the at least one test vector are unspecified bit positions. The method further includes the step of setting the values of a plurality of the unspecified bit positions using a non-random filling methodology.
    Type: Grant
    Filed: June 7, 2000
    Date of Patent: March 8, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: John G Rohrbaugh, Jeff Rearick
  • Patent number: 6859059
    Abstract: Methods for testing integrated circuits (ICs) are provided. An exemplary method, in which the IC has a first pad configured as a signal interface for components external to the IC, the first pad having a receiver configured to receive an input signal from a component external to the IC, comprises: electrically interconnecting automated test equipment (ATE) with the IC; providing at least one stimulus to the IC such that the IC measures a receiver termination characteristic of the first pad; and receiving information corresponding to the receiver termination characteristic of the first pad. Systems and integrated circuits also are provided.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: February 22, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: John G. Rohrbaugh, Jeffrey R. Rearick
  • Publication number: 20040187060
    Abstract: Systems and methods for generating test patterns are disclosed herein. One such test pattern generating method comprises receiving a netlist of a device under test (DUT), the netlist comprising regions bounded by control/observe points. At least one of the bounded regions is embedded within another bounded region. The method further comprises generating test patterns for the bounded regions using a sequence starting with the deepest embedded bounded regions.
    Type: Application
    Filed: March 21, 2003
    Publication date: September 23, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick
  • Publication number: 20040153928
    Abstract: Hierarchically-controlled automatic test pattern generation (ATPG) is provided. One embodiment comprises a method for automatically generating test patterns for testing a device under test. Briefly described, one such method comprises the steps of: receiving a hierarchical model of a device under test, the hierarchical model comprising at least one low-level design component and at least one high-level design component which contains the low-level design component; selecting a fault to be detected in the device under test; and performing an automatic test pattern generation (ATPG) algorithm on the design components based on the hierarchy of the hierarchical model.
    Type: Application
    Filed: December 17, 2002
    Publication date: August 5, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick
  • Patent number: 6762614
    Abstract: Integrated circuits (ICs) are provided. A representative IC includes a first pad that incorporates a first driver and a first receiver, with the first driver being configured to provide a first pad output signal to a component external to the IC, and the first receiver being configured to receive a first pad input signal from a component external to the IC. A first test circuit also is provided that is internal to the IC. The first test circuit is adapted to provide information corresponding to the driver strength of the first pad. Systems, methods, computer-readable media and other ICs also are provided.
    Type: Grant
    Filed: April 18, 2002
    Date of Patent: July 13, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Jeffrey R. Rearick, John G. Rohrbaugh, Shad Shepston
  • Publication number: 20040130344
    Abstract: Methods for testing integrated circuits (ICs) are provided. An exemplary method, in which the IC has a first pad configured as a signal interface for components external to the IC, the first pad having a receiver configured to receive an input signal from a component external to the IC, comprises: electrically interconnecting automated test equipment (ATE) with the IC; providing at least one stimulus to the IC such that the IC measures a receiver termination characteristic of the first pad; and receiving information corresponding to the receiver termination characteristic of the first pad. Systems and integrated circuits also are provided.
    Type: Application
    Filed: December 16, 2003
    Publication date: July 8, 2004
    Inventors: John G. Rohrbaugh, Jeffrey R. Rearick
  • Publication number: 20040123206
    Abstract: A system and method for evaluating a device under test (DUT) that utilizes a model of the DUT interfaced to DUT interface logic, which is designed to interface the DUT to automated testing equipment (ATE). By ensuring that the model includes a description of the DUT and of the DUT testing interface, conditions such as connections between ports of the IC (i.e., buddying) that may or may not be interfaced to the ATE may be included in the model to enable precise test pattern sets to be generated using the model. The test pattern sets may be used by a simulator to test the design of an IC or by ATE to test a fabricated IC having the design.
    Type: Application
    Filed: December 20, 2002
    Publication date: June 24, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick, Christopher M. Juenemann
  • Publication number: 20040123194
    Abstract: Methods for testing tri-state bus drivers of a tri-state bus are provided. One such a method can be summarized by: selecting a tri-state bus to be tested; and performing a tri-state test including at least one of a driver speed test procedure and a driver static test procedure, the driver speed test procedure including at least one of testing the selected tri-state bus for an enable line driver slow-to-turn-on condition and an enable line driver slow-to-turn-off condition, the driver static test procedure including at least one of testing the selected tri-state bus for an enable line driver stuck-on condition and an enable line driver stuck-off condition. Systems and other methods also are provided.
    Type: Application
    Filed: December 20, 2002
    Publication date: June 24, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick
  • Publication number: 20040123195
    Abstract: Systems and methods are provided to test tri-state bus drivers An embodiment of a system includes a tri-state bus to be tested, and at least one tri-state driver connected to the tri-state bus. Either a pull-up driver test circuitry or a pull-down driver test circuitry is connected to the tri-state bus to be tested, and enable the testing of the tri-state driver. An embodiment of a method for testing tri-state bus drivers comprises: selecting the tri-state bus to be tested and performing a tri-state test on the tri-state bus to be tested; switching off enable signals for all drivers on the tri-state bus, forcing the tri-state bus to a first value; setting all driver data inputs to a second value different than the first value, and determining if the first value remains on the tri-state bus.
    Type: Application
    Filed: December 20, 2002
    Publication date: June 24, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick
  • Patent number: 6741946
    Abstract: A preferred system for facilitating automated test equipment functionality within integrated circuits includes automated test equipment (ATE) configured to electrically interconnect with an integrated circuit and to provide at least one signal to the integrated circuit. A first parametric test circuit, internal to the integrated circuit, also is provided. The first parametric test circuit is adapted to electrically communicate with the automated test equipment so that, in response to receiving a signal from the automated test equipment, the first parametric test circuit measures at least one parameter of a first pad of the integrated circuit.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: May 25, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: John G. Rohrbaugh, Jeffrey R. Rearick, Shad R. Shepston
  • Patent number: 6707313
    Abstract: Systems and methods for testing integrated circuits are provided. One such method comprises: providing a target fault list corresponding to an integrated circuit, the target fault list including at least a first fault and a second fault; measuring a relationship between the first fault and the second fault, the relationship corresponding to which of the first fault and the second fault is more readily detected by automatic test pattern generation; ordering the first fault and the second fault within the target fault list in a manner corresponding to the relationship; and performing automatic test pattern generation based upon an order of the faults of the target fault list. Systems and other methods also are provided.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: March 16, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: John G Rohrbaugh, Jeff Rearick
  • Publication number: 20040044936
    Abstract: Methods for testing integrated circuits (ICs) are provided. An embodiment of a method comprises: electrically interconnecting automated test equipment (ATE) with the IC; providing at least one stimulus such that the IC determines the presence of a leakage current of the first pad;. and receiving information corresponding to the leakage current of the first pad. Systems also are provided.
    Type: Application
    Filed: June 18, 2003
    Publication date: March 4, 2004
    Inventors: Jeffrey R. Rearick, John G. Rohrbaugh, Shad Shepston
  • Publication number: 20040044972
    Abstract: A method and apparatus of carrying out a computer assisted analysis function on a hierarchical circuit model. The method is carried out by inputting the hierarchical circuit model, specifying at least one circuit block within the hierarchy as a target of the function on the target block, and simplifying the hierarchical circuit model by deleting circuit blocks not affecting the analysis function, to produce a simplified hierarchical circuit model. A computer assisted analysis function can then be carried out on the simplified hierarchical circuit model.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 4, 2004
    Inventors: John G. Rohrbaugh, Jeff Rearick, Daryl H. Allred