Patents Examined by Steven D. Radosevich
  • Patent number: 7454674
    Abstract: In one embodiment, a jitter detector comprises a logic circuit coupled to receive a plurality of inputs indicative of states captured from a plurality of outputs of a delay chain responsive to a first clock input and a plurality of clocked storage devices coupled to the logic circuit. The logic circuit is configured to identify a first input of the plurality of inputs that is: (i) captured in error from a corresponding one of the plurality of outputs of the delay chain, and (ii) the corresponding one of the plurality of outputs of the delay chain is least delayed by the delay chain among the plurality of outputs that are captured in error. The plurality of clocked storage devices are configured to accumulate an indication of which of the plurality of outputs have been captured in error over a plurality of clock cycles of the first clock input.
    Type: Grant
    Filed: January 4, 2006
    Date of Patent: November 18, 2008
    Assignee: P.A. Semi, Inc.
    Inventors: Greg M. Hess, Edgardo F. Klass, Andrew J. Demas, Ashish R. Jain
  • Patent number: 7447963
    Abstract: A plurality of integrated circuits that are used in an electronic circuit have functional interconnections and dedicated test connections. The integrated circuits receive and transmit synchronization information, such as clock signals from one integrated circuit to another successively through the chain. This permits a high-test speed. Preferably the synchronization information is serialized with test data, test results and/or commands. Preferably, the bit rate between successive integrated circuits in the chain is programmable by means of commands transmitted through the chain. Thus, different bit rates may be at different locations along the chain to reduce the delay occurred by the synchronization signals along the chain.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: November 4, 2008
    Assignee: NXP B.V.
    Inventor: Rodger Frank Schuttert
  • Patent number: 7444576
    Abstract: In a tentative target value calculation section 28, a predetermined value is subtracted from (or added to) a target value Exp to calculate a tentative target value ExpB. In a binary search executing section 25, binary search is executed, and a searching region is limited to a certain region including this tentative target value ExpB. Next, in a sequential search executing section 29, the target value Exp is searched for in an increasing direction from the tentative target value ExpB which is a start point in the limited searching region. Accordingly, both drop prevention of measurement precision and reduction of searching time are achieved consistently, and a target value is securely and normally found in a case where a sequence constituting a searching object indicates an ascending-order sequence including a decrease in a part.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: October 28, 2008
    Assignee: Advantest Corp.
    Inventor: Hideyuki Oshima
  • Patent number: 7428682
    Abstract: In relation to the built-in self-test circuit (BIST circuit) for testing CAM macros, the present invention is intended to provide a means to enable reduction in amount of materials as required for wiring channel region for signal distribution, buffer, FF, etc., and in number of LSI pins, and further, to facilitate mounting on chips. The data generators for CAM testing, inserted between the APG for RAMs and CAM macros, create data to write to the CAM macros by obtaining the address signals directly or by decoding the same signals. The APG is common to all the memory macros, and testing proper to each CAM can be carried out by changing over the operation of the inserted data generators by means of the control signal. The data generators are arranged in the proximity of the CAM macros, the circuits to be tested.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: September 23, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Yoichiro Aihara, Masahiko Nishiyama, Daisuke Sasaki
  • Patent number: 7424650
    Abstract: A method and test circuits for measuring skew between two circuit blocks of an integrated circuit. A first data signal is propagated through a first circuit block and a first clock signal is propagated through a second circuit block. The first data signal is latched synchronized to the first clock signal after propagating the first data and clock signals. The first data signal is time shifted relative to the first clock signal until the first data signal is no longer validly latching. A second data signal is propagated through the second circuit block and a second clock signal is propagated through the first circuit block. An inversion of the second data signal synchronized to an inversion of the second clock signal is latched. Then, the second data signal is time shifted relative to the second clock signal until the inversion of the second data signal is no longer validly latching.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: September 9, 2008
    Assignee: Cypress Semiconductor Corporation
    Inventors: Mohandas Palathol Mana Sivadasan, Gajender Rohilla
  • Patent number: 7395468
    Abstract: The present invention is directed to a method for debugging scan testing failures of integrated circuits. The method includes identifying a bad scan path among a set of scan paths and segmenting the bad scan path into two segments. Once the bad scan path is segmented into two segments, scan tests are run to determine whether the source of errors is near the segment point. If the number of errors generated is below a threshold, the specific location of errors can be identified by tracing the errors either manually or automatically through an automated testing unit. If the source of errors is not near the segment point, the segment point is shifted based on an analysis of the errors on the good and bad scan paths. Additional scan tests are then run and the method repeated until the location of the source of errors is found.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: July 1, 2008
    Assignee: Broadcom Corporation
    Inventor: Amar Guettaf
  • Patent number: 7386773
    Abstract: A testing procedure for distributed logic circuits that incorporates an efficient utilization of flip-flops to toggle detect for sensing output is discussed. The distributed logic circuit is a phase interpolator or a phase interpolator preceded by a DLL. The testing procedure utilizes enabling one of a plurality of independent programmable current sources and a flip-flop to toggle in response to the enabled current source to indicate a physical connection of the enabled distributed logic circuit current source.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: June 10, 2008
    Assignee: Intel Corporation
    Inventors: Tim Frodsham, Lakshminarayan Krishnamurty
  • Patent number: 7376871
    Abstract: Configurations and methods that enable the testing of CAM-specific circuitry, even if the memory is defective, are implemented by utilizing various test modes. Accordingly, the CAM can be debugged to isolate memory failures from priority encoder failures, which significantly reduces the need for design changes. The present invention provides the ability to test the CAM functions very efficiently, thereby reducing the test time.
    Type: Grant
    Filed: August 6, 2003
    Date of Patent: May 20, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: George Ernest Harris, Bryan Sheffield, Dwayne Ward
  • Patent number: 7376876
    Abstract: A test specification and test program set for a given unit under test and a given automated test equipment platform is generated in an automated manner using information stored in a repository.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: May 20, 2008
    Assignee: Honeywell International Inc.
    Inventors: Rabindra Nath Raul, Rajaah K. Vasudevan, Ranga A. Udipi
  • Patent number: 7340657
    Abstract: In an embodiment, a method includes forming a plurality of time/voltage points from a number of voltage values and from a number of time values, generating serialized data having a predetermined number of bits, comparing the serialized data to a set predetermined voltage to produce analysis data, and capturing the analysis data at a respective time data point of a plurality of time data points. The method may be implemented as part of integrated circuits, electronic assemblies, or systems.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: March 4, 2008
    Assignee: Intel Corporation
    Inventors: Jared W. Crop, David J. O'dell, Mike D. Wang
  • Patent number: 7334169
    Abstract: A memory device includes a plurality of test mode signal generating units and a plurality of test circuits. Each test mode signal generating unit generates a respective test mode signal for a respective test circuit. The test mode signal generating units generate the test mode signals in series for the test circuits. Each test mode signal generating unit may be disposed within a respective test circuit such that wiring is not necessary from the source of the test mode signals to the test circuits.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: February 19, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-Uk Chang, Gil-Shin Moon, Dong-Ho Hyun
  • Patent number: 7334174
    Abstract: A semiconductor integrated circuit device includes a programmable circuit in which information is programmed, an information holding circuit which electrically holds information programmed in the programmable circuit, a compression circuit which compresses information held in the information holding circuit, an information output circuit which outputs expected value information, and a detection circuit which checks whether information held in the information holding circuit is destroyed or not. The detecting circuit compares expected value information of the information output circuit with compression information of the information compression circuit to check destruction of information held in the information holding circuit.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: February 19, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Motohiro Enkaku
  • Patent number: 7321999
    Abstract: In one embodiment, an electronic device is tested using automated test equipment (ATE) by 1) storing different vectors of scan load data in memory of the ATE; 2) storing a scan unload subroutine in the memory of the ATE; 3) stimulating the electronic device by retrieving the different vectors of scan load data and applying them to the electronic device; and 4) capturing responses to the different vectors by repeatedly calling the scan unload subroutine, and in response thereto, storing different vectors of scan unload data in the memory.
    Type: Grant
    Filed: October 5, 2004
    Date of Patent: January 22, 2008
    Assignee: Verigy (Singapore) Pte. Ltd.
    Inventors: Domenico Chindamo, Ariadne Salagianis
  • Patent number: 7321998
    Abstract: A semiconductor integrated circuit includes a plurality of data output pins, a data processing circuit to generate output signals responsive to an input signal, and an output selection circuit with at least a normal mode and a test mode. A first group of output signals are provided to a first group of data output pins in a first test cycle of the test mode. And a second group of output signals are provided to a second group of data output pins during a second test cycle of the test mode. The semiconductor integrated circuit can be tested by means of a test device having less test pins than the output pins of the semiconductor integrated circuit under test.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: January 22, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Nam-Jung Her, Seok-Young Han
  • Patent number: 7313742
    Abstract: A logic circuit having a self-test function includes a plurality of F/Fs having at least first-, second- and last-stage scanning F/Fs, each having a clock input, a scanning input and a scanning output terminals. The scanning F/Fs are connected one another so as to supply a scanning clock signal to the clock input terminal of each scanning F/F and a signal from the scanning output terminal of the first-stage to the scanning input terminal of the second-stage for sequential logical operations. Also provided in the logic circuit are a data selector to select either an external scanning signal or a signal output from the scanning output terminal of the last-stage and fed back through a feed-back signal line and a scanning controller to supply a control signal to the data selector so as to supply the signal fed back from the last-stage to the scanning input terminal of the first-stage, thus controlling each F/F in an internal scanning mode.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: December 25, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masafumi Takahashi, Kenji Ohmori
  • Patent number: 7313741
    Abstract: An integrated semiconductor memory includes memory cells that store a first data record has at least one datum with a first or second data value and a second data record has at least one datum with the first or second data value. The integrated semiconductor memory has a combination circuit that generates the third data record on the output side from the data records fed to the combination circuit on the input side to ascertain based on the third data record whether the first and second data records have been fed to the combination circuit on the input side. The combination circuit generates the datum of the third data record with the first data value, if the first and second data records were fed to the combination circuit on the input side.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: December 25, 2007
    Assignee: Infineon Technologies AG
    Inventors: Joerg Vollrath, Marcin Gnat, Aurel von Campenhausen, Frank Schroeppel
  • Patent number: 7308622
    Abstract: An integrated memory includes command terminals for receiving command signals in a normal operation and in a test operation of the memory, and also a signal terminal for receiving a further signal, which differs from the command signals. Registers store data patterns or data topologies for use in the test operation of the memory. A register decoder circuit serves for the selection of the registers, it being possible for inputs of the register decoder circuit to be connected to the command terminals and to the signal terminal for the purpose of selection of the registers in the test operation. The invention makes it possible, for the test operation, to address an increased number of registers without driving an additional external terminal pin. A method for testing the memory is also provided.
    Type: Grant
    Filed: July 14, 2003
    Date of Patent: December 11, 2007
    Assignee: Infineon Technologies AG
    Inventors: Erwin Thalmann, Sven Boldt
  • Patent number: 7278077
    Abstract: A system for testing a synchronous link utilizing a single test pattern sequence. Components coupled via a link are each configured to generate and check test patterns according to a single repeated test pattern sequence. Test patterns which are generated are based upon two simple patterns. Each test cycle, a bit is chosen from one of the two patterns for use in generating the test pattern. A sixteen cycle test pattern sequence is utilized in which values are chosen from one or the other of the two patterns in a predetermined manner. In a bi-directional test, two components which are coupled via a link alternate driving selected values based upon the predetermined sequence. Each component may alternate driving sequences of one or more cycles. An ordering of cycles may be chosen to test various permutations of driver interaction between the respective components.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: October 2, 2007
    Assignee: Sun Microsystems, Inc.
    Inventor: Brian L. Smith
  • Patent number: 7278074
    Abstract: In one embodiment, an apparatus includes a system circuit adapted to generate at a first output terminal a first output signal in response to a data input signal and at least one system clock signal; a shadow circuit adapted to generate at a second output terminal a second output signal in response the data input signal and the at least one system clock signal; and an output joining circuit coupled to at least the first output terminal and the second output terminal.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: October 2, 2007
    Assignee: Intel Corporation
    Inventors: Subhasish Mitra, Ming Zhang, Tak M. Mak, Quan Shi, Kee Sup Kim
  • Patent number: 7266746
    Abstract: The present invention provides an integrated circuit test device and method which creates a pattern for minimizing a difference from a pattern generated by a pattern generation device. In the invention, a list of all failures assumed to be in the circuit is created, and, for example, a random number pattern is inputted so that a signal value in the circuit is defined by a logic simulation using the inputted pattern, as a result of which the controllability, observability and testability are calculated. A target failure minimizing the testability is selected from the list, for which target failure path-sensitization is performed using the controllability and observability of the input pattern, which pattern is corrected so as to minimize the number of inversions of signal values of the input pattern. A failure simulation for the target failure is also performed using the corrected pattern, and when a failure to be detected further exists, the failure is removed from the failure list.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: September 4, 2007
    Assignee: Fujitsu Limited
    Inventor: Takahisa Hiraide