Patents by Inventor Erik A. Nelson

Erik A. Nelson 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: 8854073
    Abstract: Method and apparatus for margin testing integrated circuits. The method includes selecting a clock frequency, an operating temperature range and a power supply voltage level for margin testing an integrated circuit wherein one or more of the clock frequency, the operating temperature range and the power supply voltage level is outside of the normal operating conditions of the integrated circuit; applying an asynchronously time varying power supply voltage set to the selected power supply voltage level to the integrated circuit; running the integrated circuit chip at the selected clock frequency and maintaining the integrated circuit within the selected temperature range; applying a continuous test pattern to the integrated circuit; and monitoring the integrated circuit for fails.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: October 7, 2014
    Assignee: International Business Machines Corporation
    Inventors: David A. Grosch, Marc D. Knox, Erik A. Nelson, Brian C. Noble
  • Publication number: 20130069678
    Abstract: Method and apparatus for margin testing integrated circuits. The method includes selecting a clock frequency, an operating temperature range and a power supply voltage level for margin testing an integrated circuit wherein one or more of the clock frequency, the operating temperature range and the power supply voltage level is outside of the normal operating conditions of the integrated circuit; applying an asynchronously time varying power supply voltage set to the selected power supply voltage level to the integrated circuit; running the integrated circuit chip at the selected clock frequency and maintaining the integrated circuit within the selected temperature range; applying a continuous test pattern to the integrated circuit; and monitoring the integrated circuit for fails.
    Type: Application
    Filed: September 20, 2011
    Publication date: March 21, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David Grosch, Marc D. Knox, Erik A. Nelson, Brian C. Noble
  • Patent number: 8125840
    Abstract: An approach that provides reference level generation with offset compensation for a sense amplifier is described. In one embodiment, an arbitrary reference level is generated to provide an offset that compensates for device mismatch and voltage threshold of a sense amplifier.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: February 28, 2012
    Assignee: International Business Machines Corporation
    Inventors: John E. Barth, Jr., Erik A. Nelson
  • Publication number: 20110051532
    Abstract: An approach that provides reference level generation with offset compensation for a sense amplifier is described. In one embodiment, an arbitrary reference level is generated to provide an offset that compensates for device mismatch and voltage threshold of a sense amplifier.
    Type: Application
    Filed: August 31, 2009
    Publication date: March 3, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John E. Barth, JR., Erik A. Nelson
  • Patent number: 7237165
    Abstract: A system for testing a DRAM includes DRAM blocks, the system further includes a processor based built-in self test system for generating a test data pattern, for each DRAM block, performing a write of the test data pattern into the DRAM block, performing a pause for a predetermined period of time, and performing a read of a resulting data pattern from the DRAM block. For each DRAM block, the performing the write of the test pattern into the DRAM block is performed before the performing the pause for the predetermined period of time, and the performing the read of the resulting data pattern from the DRAM block is performed after the performing the pause for the predetermined period of time, and at least a portion of the pause for the predetermined period of time of two or more the DRAM blocks overlap in time.
    Type: Grant
    Filed: November 22, 2004
    Date of Patent: June 26, 2007
    Assignee: International Business Machines Corporation
    Inventors: Laura S. Chadwick, William R. Corbin, Jeffrey H. Dreibelbis, Erik A. Nelson, Thomas E. Obremski, Toshiharu Saitoh, Donald L. Wheater
  • Patent number: 7103814
    Abstract: Technique to perform logic and embedded memory tests using logic scan chain testing procedures in parallel with memory built in self test (BIST). This is accomplished with a combination of voltage isolation between memory and logic segments, and isolation between logic and memory test clocks. A test algorithm is introduced to enable and disable the scan chain operation during BIST operation.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: September 5, 2006
    Assignee: International Business Machines Corporation
    Inventors: William R. Corbin, Brian R. Kessler, Erik A. Nelson, Thomas E. Obremski, Donald L. Wheater
  • Patent number: 7073100
    Abstract: A method and system for testing an embedded DRAM that includes DRAM blocks. The method including: generating a test data pattern in a processor based BIST system, for each DRAM block, performing a write of the test data pattern into the DRAM block, performing a pause for a predetermined period of time, and performing a read of a resulting data pattern from the DRAM block; where for each DRAM block, the write of the test data pattern into the DRAM block is performed before the pause, and the read of the resulting data pattern from each DRAM block is performed after the pause; where at least a portion of the pause of two or more of the DRAM blocks overlap in time; and for each DRAM block comparing the test data pattern to the resulting data pattern.
    Type: Grant
    Filed: November 11, 2002
    Date of Patent: July 4, 2006
    Assignee: International Business Machines Corporation
    Inventors: Laura S. Chadwick, William R. Corbin, Jeffrey H. Dreibelbis, Erik A. Nelson, Thomas E. Obremski, Toshiharu Saitoh, Donald L. Wheater
  • Patent number: 6856569
    Abstract: Multiple fuse decompression serial bitstreams support an auxiliary fuseblow capability utilizing on-chip storage and providing a composite capability of embedded memory address/data failure information. A multiple repair capability has an improved compression algorithm to compress fuse data with system level soft-set redundancy, and lends itself to self-repair design, and to provide repairs for temperature sensitive fails. An instruction based tester interface in a fuse control provides shift loaded instructions in which the sequence of test and fuse repair operations is variable to provide flexibility in the manufacturing, test and repair operations.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: February 15, 2005
    Assignee: International Business Machines Corporation
    Inventors: Erik A. Nelson, Michael R. Ouellette
  • Publication number: 20040136257
    Abstract: A system and method for merging multiple fuse decompression serial bitstreams to support an auxiliary fuseblow capability utilizing on-chip storage and providing a composite capability of embedded memory address/data failure information. The present invention provides a multiple repair capability having an improved compression algorithm to compress fuse data with system level soft-set redundancy, and lends itself to self-repair design, and to provide repairs for temperature sensitive fails. An instruction based tester interface in a fuse control provides shift loaded instructions in which the sequence of test and fuse repair operations is variable to provide flexibility in the manufacturing, test and repair operations.
    Type: Application
    Filed: January 10, 2003
    Publication date: July 15, 2004
    Applicant: International Business Machines Corporation
    Inventors: Erik A. Nelson, Michael R. Ouellette
  • Publication number: 20040093539
    Abstract: A method and system for testing a DRAM comprised of DRAM blocks. The method comprises: in a processor based built-in self test system, generating a test data pattern; for each DRAM block, performing a write of the test data pattern into the DRAM block, performing a pause for a predetermined period of time, and performing a read of a resulting data pattern from the DRAM block; wherein for each DRAM block, the performing the write of the test pattern into the DRAM block is performed before the performing the pause for the predetermined period of time, and the performing the read of the resulting data pattern from the DRAM block is performed after the performing the pause for the predetermined period of time; and wherein at least a portion of the pause for the predetermined period of time of two or more the DRAM blocks overlap in time.
    Type: Application
    Filed: November 11, 2002
    Publication date: May 13, 2004
    Applicant: International Business Machines Corporation
    Inventors: Laura S. Chadwick, William R. Corbin, Jeffrey H. Dreibelbis, Erik A. Nelson, Thomas E. Obremski, Toshiharu Saitoh, Donald L. Wheater
  • Publication number: 20040083412
    Abstract: Technique to perform logic and embedded memory tests using logic scan chain testing procedures in parallel with memory built in self test (BIST). This is accomplished with a combination of voltage isolation between memory and logic segments, and isolation between logic and memory test clocks. A test algorithm is introduced to enable and disable the scan chain operation during BIST operation.
    Type: Application
    Filed: October 25, 2002
    Publication date: April 29, 2004
    Applicant: International Business Machines Corporation
    Inventors: William R. Corbin, Brian R. Kessler, Erik A. Nelson, Thomas E. Obremski, Donald L. Wheater
  • Patent number: 6708298
    Abstract: A method for testing the data strobe window (DQS) and data valid window (tDV) of a memory device (e.g., a DDR-type memory device) using the window strobe of a testing system.
    Type: Grant
    Filed: January 23, 2001
    Date of Patent: March 16, 2004
    Assignee: International Business Machines Corporation
    Inventors: William E. Corbin, Jr., David P. Monty, Erik A. Nelson, Alan D. Norris, Steven W. Tomashot, David E. Chapman, Timothy E. Fiscus
  • Patent number: 6658604
    Abstract: To overcome these problems, the present invention generates two window strobes and uses the two window strobes to determine if skew between two signals meets predetermined criteria. One of the window strobes is used to test one of the signals, and the other window strobe is generated relative to the first window strobe. The second window strobe tests the other signal (or signals, if they are data signals). From the tests of the two window strobes, it can be determined if the skew between the first and second signals meets predetermined criteria. In particular, the two window strobes are placed relative to each other and to the signals being tested in such a way that when both window strobes indicate passing conditions, skew between the two signals is guaranteed.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: December 2, 2003
    Assignee: International Business Machines Corporation
    Inventors: William R. Corbin, David P. Monty, Erik A. Nelson, Alan D. Norris, Steven W. Tomashot, David E. Chapman, Timothy E. Fiscus
  • Patent number: 6577548
    Abstract: A method and circuit for a self timed DRAM. The circuit includes interlock circuits coupled to an extension of the DRAM. The extension does not store “real” data but mimics the operations of the DRAM. The interlock circuits, in conjunction with the extension monitor and control read and write timings of the DRAM and self adjust these timings via feedback. To properly track DRAM cell timings, the interlock circuits and extension use the same cell design and load conditions as the DRAM. The method includes: activating a wordline and reference wordline, interlocking the sense amplifiers, column select and write back functions of the primary DRAM array by monitoring the identical reference cells and the state of the bitline in the extension DRAM array.
    Type: Grant
    Filed: September 26, 2002
    Date of Patent: June 10, 2003
    Assignee: International Business Machines Corporation
    Inventors: John E. Barth, Jr., Jeffrey H. Dreibelbis, Erik A. Nelson
  • Patent number: 6449200
    Abstract: A method and structure for the invention includes an integrated memory structure having a built-in test portion. The integrated memory structure has memory cells, bitlines and wordlines connected to the memory cells, wordline decoders connected to a plurality of the wordlines, bitline restore devices connected to the bitlines for charging the bitlines during read and write operations, and a clock circuit connected to the wordlines. During a test mode the wordline decoders simultaneously select multiple wordlines that the bitline restore devices maintain in an active state and the clock circuit maintains th multiple wordlines and the bitline restore devices in an active state for a period in excess of a normal read cycle. The invention also includes transistors which are connected to the memory cells. The transistors include bitline contacts which are stressed during the test mode.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: September 10, 2002
    Assignee: International Business Machines Corporation
    Inventors: Erik A. Nelson, Harold Pilo
  • Publication number: 20020099987
    Abstract: A method for testing the data strobe window (DQS) and data valid window (tDV) of a memory device (e.g., a DDR-type memory device) using the window strobe of a testing system.
    Type: Application
    Filed: January 23, 2001
    Publication date: July 25, 2002
    Applicant: International Business Machines corporation
    Inventors: William R. Corbin, David P. Monty, Erik A. Nelson, Alan D. Norris, Steven w. Tomashot, David E. Chapman, Timothy E. Fiscus