Patents by Inventor Hiroaki Yamoto

Hiroaki Yamoto 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: 7596730
    Abstract: A test method for testing a device under test by using an event tester is provided. The test method includes: receiving a test signal generated by the event tester and applied to the device under test and sequentially writing the same to a memory; reading sequentially the written test signal from the memory at the speed higher than that of the test signal generated by the event tester and applying the same to the device under test; acquiring the output signal outputted from the device under test in response to the applied test signal and sequentially writing the same at the speed higher than that of the test signal generated by the event tester; sequentially reading the written output signal from the memory and transmitting the same at the speed lower than that of the output signal outputted from the device under test; and determining pass/fail of the transmitted output signal by the event tester.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: September 29, 2009
    Assignee: Advantest Corporation
    Inventors: Yuya Watanabe, Shigeru Sugamori, Hiroaki Yamoto
  • Publication number: 20070234146
    Abstract: A test method for testing a device under test by using an event tester is provided. The test method includes: receiving a test signal generated by the event tester and applied to the device under test and sequentially writing the same to a memory ; reading sequentially the written test signal from the memory at the speed higher than that of the test signal generated by the event tester and applying the same to the device under test; acquiring the output signal outputted from the device under test in response to the applied test signal and sequentially writing the same at the speed higher than that of the test signal generated by the event tester; sequentially reading the written output signal from the memory and transmitting the same at the speed lower than that of the output signal outputted from the device under test; and determining pass/fail of the transmitted output signal by the event tester.
    Type: Application
    Filed: March 31, 2006
    Publication date: October 4, 2007
    Applicant: Advantest Corporation
    Inventors: Yuya Watanabe, Shigeru Sugamori, Hiroaki Yamoto
  • Patent number: 7178115
    Abstract: A manufacturing process for LSIs uses an event tester simulator and an event tester to avoid prototype hold. In the LSI manufacturing method an LSI is designed under an EDA (electronic design automation) environment to produce design data of a designed LSI, and logic simulation is performed on a device model of the LSI design in the EDA environment with use of a testbench and producing a test vector file of an event format as a result of the logic simulation. Then, simulation data files are verified with use of the design data and the testbench by operating an event tester simulator, and a prototype LSI is produced through a fabrication provider by using the design data. The prototype LSI is tested by an event tester by using the test vector file and the simulation data files and test results is feedbacked to the EDA environment or the fabrication provider.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: February 13, 2007
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Patent number: 7089517
    Abstract: A method for design validation of complex IC with use of a combination of electronic design automation (EDA) tools and a design test station at high speed and low cost. The EDA tools and device simulator are linked to the event based test system to execute the original design simulation vectors and testbench and make modifications in the testbench and event based test vectors until satisfactory results are obtained. The event based test vectors are test vectors in an event format in which an event is any change in a signal which is described by its timing and the event based test system is a test system for testing an IC by utilizing the event based test vectors. Because EDA tools are linked with the event based test system, these modifications are captured to generate a final testbench that provides satisfactory results.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: August 8, 2006
    Assignee: Advantest Corp.
    Inventors: Hiroaki Yamoto, Rochit Rajsuman
  • Patent number: 7089135
    Abstract: An event based test system for testing an IC device under test (DUT) designed under an automatic electronic design (EDA) environment. The event based test system includes an event memory for storing event data derived directly from simulation of design data for an intended IC in the EDA environment where the event data to denote each event is formed with time index indicating a time length from a predetermined point and an event type indicating a type of change at an event, an event generation unit for generating test vectors based on the event data where waveform of each vector is determined by the event type and a timing of the waveform is determined by accumulating the time index of previous events, and means for supplying test vectors to the DUT and evaluating response outputs of the DUT at predetermined timings.
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: August 8, 2006
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Shigeru Sugamori, Robert F. Sauer, Hiroaki Yamoto, James Alan Turnquist, Bruce R. Parnas, Anthony Le
  • Patent number: 6944808
    Abstract: A method of evaluating a core based SoC detects and localizes faults in the cores or interconnects between the cores with high accuracy and observability. The method includes the steps of building two or more metal layers to create core I/O pads having all I/O pads and power pads on a surface of the top metal layer of the pad frame of each core, testing the SoC as a whole by applying test vectors to the SoC through chip I/O pads and evaluating response outputs of the SoC, testing each core in the SoC by applying core specific test vectors to the core through the core I/O pads on the top metal layer of the core and evaluating response outputs of the core, and finding a location of a fault when the fault is detected when testing the SoC chip as a whole or when testing each of the cores.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: September 13, 2005
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Patent number: 6791316
    Abstract: A high speed semiconductor test system is so designed that pin cards in a test head are arranged in radial directions where the DUT is placed over the center of the test head. Since each of the pin cards is arranged radially, the side which faces the center is close to the DUT, and time critical components in the pin card are formed in an area close to the side of that faces the center, thereby minimizing the round-trip-delay (RTD).Moreover, each pin card is distanced equally from the DUT. Thus, the variation in the length of path connecting between the pin card and the DUT is minimized, and accordingly, the variation in RTD is also minimized.
    Type: Grant
    Filed: September 24, 2002
    Date of Patent: September 14, 2004
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Publication number: 20040056677
    Abstract: A high speed semiconductor test system is so designed that pin cards in a test head are arranged in radial directions where the DUT is placed over the center of the test head. Since each of the pin cards is arranged radially, the side which faces the center is close to the DUT, thereby minimizing the round-trip-delay (RTD). Moreover, each pin card is distanced equally from the DUT. Thus, the variation in the length of path connecting between the pin card and the DUT is minimized, and accordingly, the variation in RTD is also minimized.
    Type: Application
    Filed: September 24, 2002
    Publication date: March 25, 2004
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Publication number: 20040019550
    Abstract: An intangible property management method and system to enumerate and account intangible property is described. The intangible property management system utilizes a computer system which uses various domains of the intangible property to enumerate and account intangible property based on relationships with various business parameters. The system is configured by a computer system for executing a program and processing data describing the intangible assets interrelated with business parameters, and a multi-dimensional chart having multiple domains which are assigned with types of intangible property and business parameters.
    Type: Application
    Filed: July 27, 2002
    Publication date: January 29, 2004
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Patent number: 6678643
    Abstract: A semiconductor test system which generates a test pattern produced based on data resultant to device logic simulation performed on a computer for an LSI device designed in an electronic design automation (EDA) environment, tests the LSI device, and feedbacks the test results to the EDA environment. The semiconductor test system includes an event file for storing event data obtained by executing device logic simulation in a design stage of an LSI device under test; an event memory for storing the event data from the event file relative to timings; means for generating a test pattern by directly using the event data from the event memory and applying the test pattern to the LSI device under test; a result data file for evaluating a response output of the LSI device under test and storing resultant evaluation data; and means for evaluating design of the LSI device based on the data stored in the result data file.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: January 13, 2004
    Assignee: Advantest Corp.
    Inventors: James Alan Turnquist, Shigeru Sugamori, Hiroaki Yamoto
  • Patent number: 6678645
    Abstract: A method and apparatus for validating SoC (system-on-a-chip) design with high accuracy and speed and low cost. The [apparatus allows to use a] method [which] includes the steps of verifying individual cores to be integrated in an SoC by evaluating a silicon IC having a function and structure identical to that of each core constituting the SoC with use of test patterns generated based on simulation testbenches produced through a design stage of the cores; verifying interfaces between the individual cores, on-chip buses of the cores and glue logic by using the silicon ICs and simulation testbenches [developed by an SoC designer] and FPGA/emulation of the glue logic; verifying core-to-core timings and SoC level timing critical paths; and performing an overall design validation by using the silicon ICs and simulation testbenches of [an] the overall SoC [and application runs].
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: January 13, 2004
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Publication number: 20030217341
    Abstract: A universal IC test system is designed to function both an event tester and a cyclized tester. The universal test system is comprised of an event tester for testing DUT by test vectors produced based on event data derived directly from simulation of design data of DUT produced in an EDA environment a cyclized tester for testing DUT by test vectors produced based on test data formulated in a cyclized format in which each test vector is defined by a waveform, a test rate, and a timing with respect to the test rate, a pin-electronics for applying the test vector to DUT and comparing a response output of DUT, and means for changing a tester mode between an event tester mode and a cyclized tester mode thereby testing DUT either by the event tester or the cyclized tester, or by both testers.
    Type: Application
    Filed: August 27, 2002
    Publication date: November 20, 2003
    Inventors: Rochit Rajsuman, Robert F. Sauer, Hiroaki Yamoto
  • Publication number: 20030217345
    Abstract: An event based test system for testing an IC device under test (DUT) designed under an automatic electronic design (EDA) environment. The event based test system includes an event memory for storing event data derived directly from simulation of design data for an intended IC in the EDA environment wherein the event data to denote each event is formed with time index indicating a time length from a predetermined point and an event type indicating a type of change at an event, an event generation unit for generating test vectors based on the event data from the event memory where waveform of each vector is determined by the event type and a timing of the waveform is determined by accumulating the time index of previous events, and means for supplying test vectors to the DUT and evaluating response outputs of the DUT at predetermined timings.
    Type: Application
    Filed: May 20, 2002
    Publication date: November 20, 2003
    Inventors: Rochit Rajsuman, Shigeru Sugamori, Robert F. Sauer, Hiroaki Yamoto, James Alan Turnquist, Bruce R. Parnas, Anthony Le
  • Publication number: 20030217343
    Abstract: A manufacturing process for LSIs uses an event tester to avoid prototype hold. The LSI manufacturing method includes the steps of: designing an LSI under an EDA (electronic design automation) environment to produce design data of a designed LSI, performing logic simulation on a device model of the LSI design in the EDA environment with use of a testbench and producing a test vector file of an event format as a result of the logic simulation, verifying simulation data files with use of the design data and the testbench by operating an event tester simulator, producing a prototype LSI through a fabrication provider by using the design data, and testing the prototype LSI by an event tester by using the test vector file and the simulation data files and feedbacking test results to the EDA environment or the fabrication provider.
    Type: Application
    Filed: April 11, 2003
    Publication date: November 20, 2003
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Patent number: 6651204
    Abstract: An event based test system has a modular architecture for simultaneously testing a plurality of semiconductor devices (DUT) including memory and logic devices. The test system detects functional faults as well as physical faults in the DUT. The test system includes two or more tester modules each having a plurality of pin units, a main frame for accommodating the two or more tester modules, a test fixture for electrically connecting the tester modules and the DUT, a host computer for controlling an overall operation of the test system, and a data storage for storing a library of algorithmic test patterns and software tools for producing memory test patterns for testing memories. Memory test algorithm and information regarding the design and configuration of the memories to be tested are specified prior to the memory testing.
    Type: Grant
    Filed: June 1, 2000
    Date of Patent: November 18, 2003
    Assignee: Advantest Corp.
    Inventors: Rochit Rajsuman, Shigeru Sugamori, Hiroaki Yamoto
  • Patent number: 6631340
    Abstract: A semiconductor test system for testing semiconductor devices has a plurality of different tester modules and an algorithmic pattern generator (ALPG) for generating an algorithmic pattern specific to an intended memory, thereby achieving a low cost and application specific memory test system. The semiconductor test system includes two or more tester modules whose performances are different from one another, an ALPG module for generating an algorithmic pattern which is specific to the memory, a test system main frame to accommodate a combination of the tester modules and the ALPG module, a test fixture for electrically connecting the tester modules and a device under test, a performance board provided on the test fixture for mounting the device under test, and a host computer for controlling an overall operation of the test system by communicating with the tester modules through a tester bus.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: October 7, 2003
    Assignee: Advantest Corp.
    Inventors: Shigeru Sugamori, Koji Takahashi, Hiroaki Yamoto
  • Publication number: 20030093737
    Abstract: An event based test system having an improved characterization tool for semiconductor device testing. The characterization map provides multi-dimensional views of device performance for debug of the design, and identification of performance weaknesses. The characterization map tool exploits the capabilities of the event based test system. The multi-dimensional views include a checkerboard map such as displaying pins versus time, a shmoo plot showing pass-fail boundary points relative to predetermined parameters, or a margin map showing a pass/fail range for pins corresponding with timing changes in one or more events.
    Type: Application
    Filed: November 13, 2001
    Publication date: May 15, 2003
    Inventors: Michael Purtell, Hiroaki Yamoto
  • Publication number: 20030074153
    Abstract: A semiconductor test system for testing semiconductor devices has a plurality of different tester modules and an algorithmic pattern generator (ALPG) for generating an algorithmic pattern specific to an intended memory in the device under test, thereby achieving a low cost and application specific memory test system. The semiconductor test system includes two or more tester modules whose performances are different from one another, an ALPG module for generating an algorithmic pattern which is specific to the memory; a test system main frame to accommodate a combination of tester modules and ALPG module, a test fixture for electrically connecting the tester modules and a device under test, a performance board provided on the test fixture for mounting the device under test, and a host computer for controlling an overall operation of the test system by communicating with the tester modules through a tester bus.
    Type: Application
    Filed: October 15, 2001
    Publication date: April 17, 2003
    Inventors: Shigeru Sugamori, Koji Takahashi, Hiroaki Yamoto
  • Publication number: 20030056163
    Abstract: A method of evaluating a core based SoC detects and localizes faults in the cores or interconnects between the cores with high accuracy and observability. The method includes the steps of building two or more metal layers to create core I/O pads having all I/O pads and power pads on a surface of the top metal layer of the pad frame of each core, testing the SoC as a whole by applying test vectors to the SoC through chip I/O pads and evaluating response outputs of the SoC, testing each core in the SoC by applying core specific test vectors to the core through the core I/O pads on the top metal layer of the core and evaluating response outputs of the core, and finding a location of a fault when the fault is detected when testing the SoC chip as a whole or when testing each of the cores.
    Type: Application
    Filed: August 22, 2002
    Publication date: March 20, 2003
    Inventors: Rochit Rajsuman, Hiroaki Yamoto
  • Patent number: 6532561
    Abstract: An event based test system is configured to test an electronics device under test (DUT) by supplying a test signal to the DUT and evaluating an output of the DUT at a timing of a strobe signal. The event based test system includes an event memory for storing timing data of each event formed with an integer multiple of a reference clock period and a fraction of the reference clock period wherein the timing data represents a time difference between a current event and a reference point, an address sequencer for generating address data for accessing the event memory, a timing count and scaling logic for generating an event start signal, an event generation unit for generating each event based on the event start signal and data indicating the fraction of the reference clock period, and a host computer for controlling an overall operation of the event based test system.
    Type: Grant
    Filed: September 25, 1999
    Date of Patent: March 11, 2003
    Assignee: Advantest Corp.
    Inventors: James Alan Turnquist, Shigeru Sugamori, Rochit Rajsuman, Hiroaki Yamoto