Patents by Inventor Cedric Lichtenau

Cedric Lichtenau 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: 9910090
    Abstract: Aspects include techniques for bypassing an encoded latch on a chip during a test-pattern scan and using on-chip circuitry to generate a desired encoded pattern, which is inserted into a scan-bypassed latch, to test the on-chip circuitry for defects. A computer-implemented method may include applying a global control bit to the chip; initializing a scan of the chip while bypassing the encoded latch; and applying an extra scan clock to initiate the encoded latch after completing the scan, wherein the encoded latch is updated with check bits generated by the on-chip circuitry.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: March 6, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Michael Fee, Ronald J. Frishmuth, Mary P. Kusko, Cedric Lichtenau
  • Patent number: 9886408
    Abstract: A protection circuit can be used with a computer system having a master device and at least one slave device that are connected by an inter-integrated circuit (I2C) bus. A first access request is received that includes an address that identifies a first slave device. In response to a permissible mode, the first access request is communicated to the first slave device using the I2C bus. A sticky protection bit can be set. In response to the sticky protection bit being set, the protection circuit can be placed in a protected mode. A second access request is received. The second access request can be determined to be a protected access to the first slave device. In response to the determining and the protected mode, the second access request to the first slave device can be denied.
    Type: Grant
    Filed: October 26, 2015
    Date of Patent: February 6, 2018
    Assignee: International Business Machines Corporation
    Inventors: Santosh Balasubramanian, Pradeep N. Chatnahalli, Andreas Koenig, Cedric Lichtenau
  • Patent number: 9870200
    Abstract: Arithmetic logic circuitry is provided for performing a floating point arithmetic add/subtract operation on first and second floating point numbers. The method includes: generating a guard digit for the first or second number by transforming the first and second numbers by a compressing function; determining a result depending on the arithmetic operation, a sum of the transformed floating point numbers, and first and second differences of the transformed floating point numbers, and determining a corresponding result plus one by additionally adding a value of one to the result; generating injection values for rounding the final result; generating injection carry values based on the transformed first and second numbers and the injection values; and selecting the final result from the result, the result plus one, and a least significant digit, based on the injection carry values and the end around carry signals.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: January 16, 2018
    Assignee: International Business Machines Corporation
    Inventors: Steven R. Carlough, Klaus M. Kroener, Petra Leber, Cedric Lichtenau, Silvia M. Mueller
  • Patent number: 9858229
    Abstract: A protection circuit can be used with a computer system having a master device and at least one slave device that are connected by an inter-integrated circuit (I2C) bus. A first access request is received that includes an address that identifies a first slave device. In response to a permissible mode, the first access request is communicated to the first slave device using the I2C bus. A sticky protection bit can be set. In response to the sticky protection bit being set, the protection circuit can be placed in a protected mode. A second access request is received. The second access request can be determined to be a protected access to the first slave device. In response to the determining and the protected mode, the second access request to the first slave device can be denied.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: January 2, 2018
    Assignee: International Business Machines Corporation
    Inventors: Santosh Balasubramanian, Pradeep N. Chatnahalli, Andreas Koenig, Cedric Lichtenau
  • Publication number: 20170285104
    Abstract: A tool for determining unknown sources in a circuit design for exclusion from logic built-in self test (LBIST) verification for the circuit. Responsive to initializing each of one or more latches in one or more test channels of the circuit design being tested, the tool determines whether a latch of the one or more latches is corrupted by an unknown source. The tool gathers each of the one or more latches determined to be an unknown source after a capture clock phase. The tool performs a backward traverse of logic circuitry feeding each of the one or more latches determined to be an unknown source. The tool verifies that a fence on one or more unknown source nets associated with each of the one or more latches blocked the unknown source from contributing to a test signature.
    Type: Application
    Filed: June 21, 2017
    Publication date: October 5, 2017
    Inventors: Satya R. S. Bhamidipati, Mary P. Kusko, Cedric Lichtenau, Srinivas V. N. Polisetty
  • Patent number: 9779258
    Abstract: Secure extraction of state information of a computer system is provided. A method includes obtaining, by a security engine of a system, a public encryption key associated with a private decryption key; generating an extraction key that is inaccessible outside of the security engine; encrypting the extraction key with the public encryption key, to thereby obtain an encrypted extraction key; collecting state information of the system; encrypting the collected state information with the extraction key and storing the encrypted collected state information; and based on a request for access to the stored encrypted collected state information by a request for the extraction key, providing the extraction key to facilitate decryption of the stored encrypted state information.
    Type: Grant
    Filed: October 28, 2015
    Date of Patent: October 3, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: William E. Hall, Andreas Koenig, Cedric Lichtenau, Elaine Rivette Palmer, Thomas Pflueger, Peter A. Sandon
  • Publication number: 20170261550
    Abstract: Aspects include techniques for bypassing an encoded latch on a chip during a test-pattern scan and using on-chip circuitry to generate a desired encoded pattern, which is inserted into a scan-bypassed latch, to test the on-chip circuitry for defects. A computer-implemented method may include applying a global control bit to the chip; initializing a scan of the chip while bypassing the encoded latch; and applying an extra scan clock to initiate the encoded latch after completing the scan, wherein the encoded latch is updated with check bits generated by the on-chip circuitry.
    Type: Application
    Filed: March 8, 2016
    Publication date: September 14, 2017
    Inventors: Michael Fee, Ronald J. Frishmuth, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170261556
    Abstract: Aspects include techniques for implementing a clock path technique for using on-chip circuitry to generate a correct encode pattern to test the on-chip circuitry for encoding and correction of a chip. A computer-implemented method may include initializing a scan of the chip including data and a set of check bits protecting the data; applying a global control bit to a latch on the chip; and applying an additional clock to the latch so the check bits are updated using the on-chip circuitry.
    Type: Application
    Filed: March 8, 2016
    Publication date: September 14, 2017
    Inventors: Michael Fee, Ronald J. Frishmuth, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170261557
    Abstract: Aspects include techniques for implementing a clock path technique for using on-chip circuitry to generate a correct encode pattern to test the on-chip circuitry for encoding and correction of a chip. A computer-implemented method may include initializing a scan of the chip including data and a set of check bits protecting the data; applying a global control bit to a latch on the chip; and applying an additional clock to the latch so the check bits are updated using the on-chip circuitry.
    Type: Application
    Filed: February 6, 2017
    Publication date: September 14, 2017
    Inventors: Michael Fee, Ronald J. Frishmuth, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170261555
    Abstract: Aspects include techniques for bypassing an encoded latch on a chip during a test-pattern scan and using on-chip circuitry to generate a desired encoded pattern, which is inserted into a scan-bypassed latch, to test the on-chip circuitry for defects. A computer-implemented method may include applying a global control bit to the chip; initializing a scan of the chip while bypassing the encoded latch; and applying an extra scan clock to initiate the encoded latch after completing the scan, wherein the encoded latch is updated with check bits generated by the on-chip circuitry.
    Type: Application
    Filed: February 6, 2017
    Publication date: September 14, 2017
    Inventors: Michael Fee, Ronald J. Frishmuth, Mary P. Kusko, Cedric Lichtenau
  • Patent number: 9734126
    Abstract: A system and method for controlling post-silicon configurable instruction behavior are provided. For example, the method includes receiving data related to a compute circuit. The method also includes detecting a data pattern in the data. The method further includes determining that the data pattern is a special case that the compute circuit may handle improperly. The method also includes selecting a value from a post-silicon configurable data set based on the detected data. Further, the method includes changing a behavior of the compute circuit to produce a different output result based on the value selected from the post-silicon configurable data set.
    Type: Grant
    Filed: October 10, 2016
    Date of Patent: August 15, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: James R. Cuffney, Nicol Hofmann, Michael Klein, Petra Leber, Cédric Lichtenau, Silvia M. Mueller, Timothy J. Slegel
  • Publication number: 20170220319
    Abstract: A binary fused multiply-add floating-point unit configured to operate on an addend, a multiplier, and a multiplicand. The unit is configured to receive as the addend an unrounded result of a prior operation executed in the unit via an early result feedback path; to perform an alignment shift of the unrounded addend on an unrounded exponent and an unrounded mantissa; as well as perform a rounding correction for the addend in parallel to the actual alignment shift, responsive to a rounding-up signal.
    Type: Application
    Filed: June 29, 2016
    Publication date: August 3, 2017
    Inventors: Michael Klein, Klaus M. Kroener, Cédric Lichtenau, Silvia Melitta Mueller
  • Publication number: 20170220318
    Abstract: A binary fused multiply-add floating-point unit configured to operate on an addend, a multiplier, and a multiplicand. The unit is configured to receive as the addend an unrounded result of a prior operation executed in the unit via an early result feedback path; to perform an alignment shift of the unrounded addend on an unrounded exponent and an unrounded mantissa; as well as perform a rounding correction for the addend in parallel to the actual alignment shift, responsive to a rounding-up signal.
    Type: Application
    Filed: February 1, 2016
    Publication date: August 3, 2017
    Inventors: Michael Klein, Klaus M. Kroener, Cédric Lichtenau, Silvia Melitta Mueller
  • Publication number: 20170192055
    Abstract: Aspects include a method for logic built-in self-testing (LBIST) for use in an integrated circuit with scan chains. The method includes programming a product control generator and a pattern generator with an LBIST pattern comprising at least a number of loops. The LBIST pattern is executed by generating scan-in test values for scan chains with the pattern generator and controlling at least one test parameter with the product control generator. Scan-out responses are collected from the scan chains in a signature register, and a start request is received from a chip tester. The LBIST is started in response to the start request. Test summary data is reported to the chip tester before the whole number of loops has been executed.
    Type: Application
    Filed: January 5, 2016
    Publication date: July 6, 2017
    Inventors: Satya R.S. Bhamidipati, Raghu G. Gopalakrishnasetty, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170192054
    Abstract: Aspects include a system having logic built-in self-test (LBIST) circuitry for use in an integrated circuit with scan chains. The system includes a pattern generator configured for generating scan-in test values for said scan chains; a signature register configured for collecting scan-out responses from said scan chains after a clock sequence; an on-product control generator configured for controlling at least one test parameter; one or more microcode array or memory elements configured to receive inputs to initialize fields in the microcode array or memory elements; and a test controller. The test controller includes a reader component configured for reading test parameters from a field of the microcode array or the memory elements; and a programming component configured for configuring the on-product control generator and the pattern generator with a LBIST pattern according to the read test parameters.
    Type: Application
    Filed: January 5, 2016
    Publication date: July 6, 2017
    Inventors: Satya R.S. Bhamidipati, Raghu G. Gopalakrishnasetty, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170192057
    Abstract: Aspects include a method for logic built-in self-testing (LBIST) for use in an integrated circuit with scan chains. The method includes programming a product control generator and a pattern generator with an LBIST pattern comprising at least a number of loops. The LBIST pattern is executed by generating scan-in test values for scan chains with the pattern generator and controlling at least one test parameter with the product control generator. Scan-out responses are collected from the scan chains in a signature register, and a start request is received from a chip tester. The LBIST is started in response to the start request. Test summary data is reported to the chip tester before the whole number of loops has been executed.
    Type: Application
    Filed: June 13, 2016
    Publication date: July 6, 2017
    Inventors: SATYA R.S. BHAMIDIPATI, RAGHU G. GOPALAKRISHNASETTY, MARY P. KUSKO, CEDRIC LICHTENAU
  • Patent number: 9689920
    Abstract: A tool for determining unknown sources in a circuit design for exclusion from logic built-in self test (LBIST) verification for the circuit. The tool initializes, by one or more computer processors, one or more nets contained in an initial nets list, wherein the initial nets list is a representation of a circuit design being tested. The tool removes, by one or more computer processors, the one or more nets initialized in response to initialization of each of one or more latches in one or more test channels of the circuit design being tested. The tool determines, by one or more computer processors, whether a latch of the one or more latches is corrupted by an unknown source.
    Type: Grant
    Filed: November 13, 2015
    Date of Patent: June 27, 2017
    Assignee: International Business Machines Corporation
    Inventors: Satya R. S. Bhamidipati, Mary P. Kusko, Cedric Lichtenau, Srinivas V. N. Polisetty
  • Publication number: 20170176531
    Abstract: A number of switching transitions of flip-flops during testing is kept below a threshold. Scan-in test data is applied to the flip-flops. Testing result data scanned-out from the flip-flops is captured, and a prediction is made of a number of switching transitions of the flip-flops between a current capture clock cycle and a next capture clock cycle. Furthermore, the testing setup values are modified before the next testing cycle is executed based on the prediction.
    Type: Application
    Filed: March 9, 2017
    Publication date: June 22, 2017
    Inventors: Satya Rama S. Bhamidipati, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170176532
    Abstract: A number of switching transitions of flip-flops during testing is kept below a threshold. Scan-in test data is applied to the flip-flops. Testing result data scanned-out from the flip-flops is captured, and a prediction is made of a number of switching transitions of the flip-flops between a current capture clock cycle and a next capture clock cycle. Furthermore, the testing setup values are modified before the next testing cycle is executed based on the prediction.
    Type: Application
    Filed: March 9, 2017
    Publication date: June 22, 2017
    Inventors: Satya Rama S. Bhamidipati, Mary P. Kusko, Cedric Lichtenau
  • Publication number: 20170161077
    Abstract: A processor with multiple execution units for instruction processing is provided. The processor comprises an instruction decode and issue logic and a control logic for resolving register access conflicts between subsequent instructions and a dependency cache, which comprises a receiving logic for receiving an execution unit indicator indicative of the execution unit the instruction is planned to be executed on, a storing logic responsive to the receiving logic for storing the received execution unit indicator, and a retrieving logic responsive to a request from the instruction decode and issue logic for providing the stored execution unit indicator for an instruction. The instruction decode and issue logic is adapted for requesting execution unit indicator for an instruction from the dependency cache and to assign the instruction to one respective of the execution units dependent on the execution unit indicator received from the dependency cache.
    Type: Application
    Filed: December 2, 2015
    Publication date: June 8, 2017
    Inventors: Peter Altevogt, Cedric Lichtenau, Thomas Pflueger