Patents by Inventor Xiaoqing Wen

Xiaoqing Wen 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: 9696377
    Abstract: A broadcaster, system, and method for reducing test data volume and test application time in an ATE (automatic test equipment) in a scan-based integrated circuit. The scan-based integrated circuit contains multiple scan chains, each scan chain comprising multiple scan cells coupled in series. The broadcaster is a combinational logic network coupled to an optional virtual scan controller and an optional scan connector. The virtual scan controller controls the operation of the broadcaster. The system transmits virtual scan patterns stored in the ATE and generates broadcast scan patterns through the broadcaster for testing manufacturing faults in the scan-based integrated circuit. The number of scan chains that can be supported by the ATE is significantly increased. Methods are further proposed to reorder scan cells in selected scan chains, to generate the broadcast scan patterns and virtual scan patterns, and to synthesize the broadcaster and a compactor in the scan-based integrated circuit.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: July 4, 2017
    Assignee: SYNTEST TECHNOLOGIES, INC.
    Inventors: Laung-Terng Wang, Hsin-Po Wang, Xiaoqing Wen, Meng-Chyi Lin, Shyh-Horng Lin, Ta-Chia Yeh, Sen-Wei Tsai, Khader S. Abdel-Hafez
  • Patent number: 9678156
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: June 13, 2017
    Assignee: SYNTEST TECHNOLOGIES, INC.
    Inventors: Laung-Terng Wang, Po-Ching Hsu, Xiaoqing Wen
  • Publication number: 20160131707
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Application
    Filed: January 19, 2016
    Publication date: May 12, 2016
    Inventors: Laung-Terng Wang, Po-Ching Hsu, Xiaoqing Wen
  • Patent number: 9316688
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: April 19, 2016
    Assignee: Syntest Technologies, Inc.
    Inventors: Laung-Terng Wang, Po-Ching Hsu, Xiaoqing Wen
  • Patent number: 9274168
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Grant
    Filed: July 21, 2015
    Date of Patent: March 1, 2016
    Assignee: SYNTEST TECHNOLOGIES, INC.
    Inventors: Laung-Terng Wang, Po-Ching Hsu, Xiaoqing Wen
  • Publication number: 20150338465
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Application
    Filed: July 21, 2015
    Publication date: November 26, 2015
    Inventors: Laung-Terng WANG, Po-Ching HSU, Xiaoqing WEN
  • Publication number: 20150316616
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Application
    Filed: June 22, 2015
    Publication date: November 5, 2015
    Inventors: LAUNG-TERNG WANG, PO-CHING HSU, XIAOQING WEN
  • Patent number: 9091730
    Abstract: A method for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in an integrated circuit or circuit assembly in scan-test or self-test mode, where N>1, each clock domain having one capture clock and a plurality of scan cells, each capture clock comprising a plurality of capture clock pulses; said method comprising: (a) generating and shifting-in N test stimuli to all said scan cells within said N clock domains in said integrated circuit or circuit assembly during a shift-in operation; (b) applying an ordered sequence of capture clocks to all said scan cells within said N clock domains, the ordered sequence of capture clocks comprising at least a plurality of capture clock pulses from two or more selected capture clocks placed in a sequential order such that all clock domains are never triggered simultaneously during a capture operation; and (c) analyzing output responses of all said scan cells to locate any faults therein.
    Type: Grant
    Filed: November 27, 2013
    Date of Patent: July 28, 2015
    Assignee: SYNTEST TECHNOLOGIES, INC.
    Inventors: Laung-Terng Wang, Po-Ching Hsu, Xiaoqing Wen
  • Patent number: 8775985
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: July 8, 2014
    Assignee: Syntest Technologies, Inc.
    Inventors: Laung-Terng Wang, Xiaoqing Wen
  • Patent number: 8589751
    Abstract: The provided are a don't-care-bit identification method and program for identifying don't-care-bits from the first and the second input vectors in an input-vector pair while keeping the sensitization status of paths, in a combinational circuit, sensitized by applying the first and the second input vectors in serial to input lines of combinational circuit. The method identifies an unspecified bit from the first and the second input vectors V1 and V2 composed of logic values 0 and 1, which are applied to the combinational portion in a sequential circuit or to an independent combinational circuit. The method includes an identification step for identifying an unspecified bit from the first and the second input vectors, while keeping sensitization status of a part of or all of the paths, sensitized by applying the first and the second input vectors.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: November 19, 2013
    Assignee: Lptex Corporation
    Inventors: Kohei Miyase, Xiaoqing Wen, Seiji Kajihara
  • Publication number: 20130305200
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Application
    Filed: March 18, 2013
    Publication date: November 14, 2013
    Inventors: Laung-Terng WANG, Xiaoqing WEN
  • Patent number: 8543950
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: September 24, 2013
    Assignee: Syntest Technologies, Inc.
    Inventors: Laung-Terng (L.-T.) Wang, Augusli Kifli, Fei-Sheng Hsu, Shih-Chia Kao, Xiaoqing Wen, Shyh-Horng Lin, Hsin-Po Wang
  • Patent number: 8453023
    Abstract: Logic value determination method and program for identifying unspecified bits and determining logic values shortly. The method enables to control the total number of logic value differences between corresponding input and output lines of combinational circuit. The method includes the first step for determining, when output has a logic value and input has an unspecified value, that the unspecified bit has the logic value of output, the second step for determining, when output has an unspecified value and input has a logic value, the logic value of the unspecified bit by justification, and the third step for calculating, when input and output both have unspecified values, probabilities of output to have 0 and 1, and determining the logic value of the unspecified bit based on the difference between the probabilities. The third step is repeated until the total number reaches a target value.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: May 28, 2013
    Assignee: LPTEX Corporation
    Inventors: Kohei Miyase, Xiaoqing Wen, Seiji Kajihara
  • Patent number: 8429472
    Abstract: Provided are a generation device to reduce launch switching activity, yield loss risk, and power consumption of testing, even in the at-speed scan testing, even with a small number of don't-care (X) bits in input bits as in test compression, without any impact on test data volume, fault coverage, performance, and circuit design, by putting focus on internal lines in the circuit. The generation device includes a target internal line selection unit, a target internal line distinction unit, an identification unit that identifies a bit to be an unspecified bit and a bit to be a logic bit in the input bits, and an assignment unit that assigns a logic value 1 or a logic value 0 to unspecified bits in the input bits. The identification unit includes an unspecified bit identification unit and an input logic bit identification unit.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: April 23, 2013
    Assignee: National University Corporation Kyushu University Institute of Technology
    Inventors: Kohei Miyase, Xiaoqing Wen, Seiji Kajihara, Yuta Yamato
  • Publication number: 20120246604
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Application
    Filed: June 7, 2012
    Publication date: September 27, 2012
    Applicant: Syntest Technologies, Inc.
    Inventors: Laung-Terng (L. -T.) WANG, Augusli Kifli, Fei-Sheng Hsu, Shih-Chia Kao, Xiaoqing Wen, Shyh-Horag Lin, Hsin-Po Wang
  • Patent number: 8219945
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: July 10, 2012
    Assignee: Syntest Technologies, Inc.
    Inventors: Laung-Terng Wang, Xiaoqing Wen
  • Patent number: 8117513
    Abstract: In a combinational portion, when there is one or more unspecified bits in pseudo external input lines and there is no unspecified bit in pseudo external output lines, an assigning operation is carried out. In the combinational portion, when there is one or more unspecified bits in the pseudo external output lines and there is no unspecified bit in the pseudo external input lines, first and second justifying operations are carried out, and a necessary logic value is determined for an unspecified bit of the test cube. In the combinational portion, when there are one more unspecified bits not only in the pseudo external input lines but also the pseudo external output lines, an assigning operation, a justifying operation or first and second assigning/justifying operations are performed upon a focused bit pair.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: February 14, 2012
    Assignee: LPTEX Corporation
    Inventors: Xiaoqing Wen, Seiji Kajihara
  • Publication number: 20110209024
    Abstract: Provided are a generation device and the like for generating a new vector whose volume can be reduced rapidly when an output pattern derived from a decompressor of a logic circuit under test includes an unspecified bit in relation to the logic circuit under test. The output pattern includes unspecified bits. In step SS1, classification unit classifies the unspecified bits and determines if an unspecified bit is an implied bit or not. The implied bit is an unspecified bit if its value is a logic value determined as logic value 0 or 1 relating to logic bits in the initial vector and according to a predetermined condition (such as compressibility) among bits in the initial vector derived from the upstream logic circuit 1. In step SS1, the unspecified bits which are not implied bits are classified as free bits. The classification unit classifies free bit sets in step SS2, and further classifies free bits to identify compatible free bit sets.
    Type: Application
    Filed: October 5, 2009
    Publication date: August 25, 2011
    Applicants: KYUSHU INSTITUTE OF TEHNOLOGY, NATIONAL TAIWAN UNIVERSITY
    Inventors: Meng-Fan Wu, Jiun-Lang Huang, Xiaoqing Wen, Kohei Miyase
  • Patent number: 8001437
    Abstract: A test pattern generation method for determining if a combinational portion 17 is defective, by applying test patterns to a semiconductor integrated circuit 10 and comparing responses to the test patterns with expected responses, the method including: a first step of generating test patterns having logic bits for detecting defects and unspecified bits; a second step of selecting critical paths 19, 19a, 19b generated by the application of the test patterns; a third step of identifying critical gates on the critical paths 19, 19a, 19b; and a fourth step of determining unspecified bits so that a critical capture transition metric, which indicates the number of the critical gates whose states are changed, is reduced; wherein by reducing the critical capture transition metric, output delays from the critical paths 19, 19a, 19b are prevented, and thereby false testing can be avoided.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: August 16, 2011
    Assignee: Kyushu Institute of Technology
    Inventors: Xiaoqing Wen, Kohei Miyase, Seiji Kajihara
  • Publication number: 20110197171
    Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).
    Type: Application
    Filed: February 18, 2011
    Publication date: August 11, 2011
    Applicant: Syntest Technologies, Inc.
    Inventors: Laung-Terng (L.-T.) WANG, Xiaoqing Wen