Patents by Inventor Darren L. Anand

Darren L. Anand 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: 8773920
    Abstract: A reference generator with programmable m and b parameters and methods of use are provided. A circuit includes a first generator operable to generate a first voltage including a fraction of a supply voltage. The circuit further includes a second generator operable to generate a second voltage. The circuit further includes a mixer and buffer circuit operable to output a reference voltage including a sum of the first and second voltages.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: July 8, 2014
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield
  • Patent number: 8649239
    Abstract: Disclosed are embodiments of a multi-bank random access memory (RAM) structure that provides signal buffering at both the global and local connector level for improved performance. Specifically, inverters are incorporated into the global connector(s), which traverse groups of memory banks and which transmit signals (e.g., address signals, control signals, and/or data signals) from a memory controller, and also into alternating groups of local connectors, which connect nodes on the global connector(s) to corresponding groups of memory banks, such that any of the signals that are received by the memory banks from the memory controller via the global and local connectors are buffered by an even number of inverters and are thereby true signals. Signal buffering at both the global and local connector level results in relatively fast slews, short propagation delays, and low peak power consumption with minimal, if any, increase in area consumption.
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: February 11, 2014
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield, Mark D. Jacunski, Matthew C. Lanahan
  • Publication number: 20130315022
    Abstract: Disclosed are embodiments of a multi-bank random access memory (RAM) structure that provides signal buffering at both the global and local connector level for improved performance. Specifically, inverters are incorporated into the global connector(s), which traverse groups of memory banks and which transmit signals (e.g., address signals, control signals, and/or data signals) from a memory controller, and also into alternating groups of local connectors, which connect nodes on the global connector(s) to corresponding groups of memory banks, such that any of the signals that are received by the memory banks from the memory controller via the global and local connectors are buffered by an even number of inverters and are thereby true signals. Signal buffering at both the global and local connector level results in relatively fast slews, short propagation delays, and low peak power consumption with minimal, if any, increase in area consumption.
    Type: Application
    Filed: May 24, 2012
    Publication date: November 28, 2013
    Applicant: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield, Mark D. Jacunski, Matthew C. Lanahan
  • Publication number: 20130215686
    Abstract: A reference generator with programmable m and b parameters and methods of use are provided. A circuit includes a first generator operable to generate a first voltage including a fraction of a supply voltage. The circuit further includes a second generator operable to generate a second voltage. The circuit further includes a mixer and buffer circuit operable to output a reference voltage including a sum of the first and second voltages.
    Type: Application
    Filed: February 21, 2012
    Publication date: August 22, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Darren L. ANAND, John A. FIFIELD
  • Patent number: 8484543
    Abstract: Error correction is selectively applied to data, such as repair data to be stored in a fusebay for BIST/BISR on an ASIC or other semiconductor device. Duplicate bit correction and error correction code state machines may be included, and selectors, such as multiplexers, may be used to enable one or both types of correction. Each state machine may include an indicator, such as a “sticky bit,” that may be activated when its type of correction is encountered. The indicator(s) may be used to develop quality and yield control criteria during manufacturing test of parts including embodiments of the invention.
    Type: Grant
    Filed: August 8, 2011
    Date of Patent: July 9, 2013
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, Kevin W. Gorman, Michael R. Ouellette, Michael A. Ziegerhofer
  • Publication number: 20130042166
    Abstract: Error correction is selectively applied to data, such as repair data to be stored in a fusebay for BIST/BISR on an ASIC or other semiconductor device. Duplicate bit correction and error correction code state machines may be included, and selectors, such as multiplexers, may be used to enable one or both types of correction. Each state machine may include an indicator, such as a “sticky bit,” that may be activated when its type of correction is encountered. The indicator(s) may be used to develop quality and yield control criteria during manufacturing test of parts including embodiments of the invention.
    Type: Application
    Filed: August 8, 2011
    Publication date: February 14, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Darren L. Anand, Kevin W. Gorman, Michael R. Ouellette, Michael A. Ziegerhofer
  • Publication number: 20120036315
    Abstract: A memory circuit comprises a memory array including a plurality of memory cells, multiple word lines, and at least one bit line. Each of the memory cells is coupled to a unique pair of a bit line and a word line for selectively accessing the memory cells. The memory circuit further includes at least one control circuit coupled to the word lines and operative to selectively change an operation of the memory array between a first data storage mode and at least a second data storage mode as a function of at least one control signal supplied to the control circuit. In the first data storage mode, each of the memory cells is allocated to a corresponding stored logic bit, and in the second data storage mode, at least two memory cells are allocated to a corresponding stored logic bit.
    Type: Application
    Filed: August 9, 2010
    Publication date: February 9, 2012
    Applicant: International Business Machines Corporation
    Inventors: William R. Reohr, Darren L. Anand, Mark D. Jacunski
  • Patent number: 7984329
    Abstract: A system and method for providing DRAM device-level repair via address remappings external to the device. A system includes a memory controller having an interface to one or more memory devices via a memory module. The memory devices include addressable redundant and non-redundant memory blocks. The memory controller also includes a mechanism for utilizing one or more redundant memory blocks in place of one or more failing non-redundant memory blocks via an address remapping external to the memory device. The remapping occurs while the system is on-line.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: July 19, 2011
    Assignee: International Business Machines Corporation
    Inventors: Luis A. Lastras-Montano, Darren L. Anand, Jeffrey H. Dreibelbis, Charles A. Kilmer, Warren E. Maule, Robert B. Tremaine
  • Patent number: 7920003
    Abstract: A delay circuit with a delay equal to the percentage of the input pulse width is described. In one embodiment, the ratio of the discharge current to the charge-up current of a timing capacitor is used to determine the percentage of the input pulse width used for the output delay. In a first timing phase, the input pulse width is stored as a voltage on the timing capacitor. In a second timing phase, the output is delayed by a percentage of the input pulse width. In a third timing phase, the circuit is restored to the trip point to remove sensitivity to process variation or applied conditions variation such as voltage or temperature (P-V-T variation), and be ready for the next timing cycle.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: April 5, 2011
    Assignee: International Business Machines Corporation
    Inventor: Darren L. Anand
  • Patent number: 7917806
    Abstract: The status of multiple on-chip power supply systems is indicated for use in modifying chip test flow and diagnosing chip failure. Digital compliance signals are received, each compliance signal associated with one of multiple on-chip power supplies. Each power supply has an associated compliance level, and each compliance signal indicates whether its associated power supply is operating at the associated compliance level. The compliance signals are converted into a power supply status signal indicating status of the compliance signals associated with the power supply. The power supply status signal is output. If a power supply is operating at its associated compliance level, the output power supply status signal indicates that the power supply is passing. If the power supply is not operating at its associated compliance level, the output power supply status signal indicates that the power supply is failing. If a power supply is failing, a memory test may be aborted, simplifying chip failure diagnosis.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: March 29, 2011
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield, Kevin W. Gorman
  • Patent number: 7916826
    Abstract: The invention provides a circuit that can observe data within shift registers without altering the data. The circuit includes selectors connected to the inputs and outputs of the shift registers. The selectors selectively connect the input with the output of a selected shift register to form a wiring loop for the selected shift register. A control device connected to the wiring loop uses the wiring loop to cause the data to be continually transferred from the output of the selected shift register to the input of the selected shift register and back through the selected shift register in a circular manner. The control device includes a counter used for determining the length of a selected shift register and a set of registers to store, for future use when rotating data in the shift registers, the length of each shift register. The control device also includes a data output accessible from outside the circuit.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: March 29, 2011
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John R. Goss, Peter O. Jakobsen, Michael R. Ouellette, Thomas O. Sopchak, Donald L. Wheater
  • Patent number: 7911820
    Abstract: An apparatus for regulating eFUSE programming current includes a current control generator receiving an input reference current through a first current path of reference fuses, the input reference current proportional to a desired eFUSE programming current; a second current path including a reference programming FET and a second group of reference fuses; and a voltage comparator coupled to a gate terminal of the reference programming FET so as to adjust the gate voltage of the reference programming FET to equalize a first voltage across the first current path with a second voltage across the second current path. The gate voltage of the reference programming FET is an output of the current control generator, coupled to corresponding gates of one or more selected programming devices of an eFUSE array such that the selected programming devices source the desired eFUSE programming current to a selected eFUSE to be programmed.
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: March 22, 2011
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield, John R. Goss
  • Publication number: 20110063007
    Abstract: A delay circuit with a delay equal to the percentage of the input pulse width is described. In one embodiment, the ratio of the discharge current to the charge-up current of a timing capacitor is used to determine the percentage of the input pulse width used for the output delay. In a first timing phase, the input pulse width is stored as a voltage on the timing capacitor. In a second timing phase, the output is delayed by a percentage of the input pulse width. In a third timing phase, the circuit is restored to the trip point to remove sensitivity to process variation or applied conditions variation such as voltage or temperature (P-V-T variation), and be ready for the next timing cycle.
    Type: Application
    Filed: September 16, 2009
    Publication date: March 17, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Darren L. Anand
  • Publication number: 20100014373
    Abstract: An apparatus for regulating eFUSE programming current includes a current control generator receiving an input reference current through a first current path of reference fuses, the input reference current proportional to a desired eFUSE programming current; a second current path including a reference programming FET and a second group of reference fuses; and a voltage comparator coupled to a gate terminal of the reference programming FET so as to adjust the gate voltage of the reference programming FET to equalize a first voltage across the first current path with a second voltage across the second current path. The gate voltage of the reference programming FET is an output of the current control generator, coupled to corresponding gates of one or more selected programming devices of an eFUSE array such that the selected programming devices source the desired eFUSE programming current to a selected eFUSE to be programmed.
    Type: Application
    Filed: July 21, 2008
    Publication date: January 21, 2010
    Inventors: Darren L. Anand, John A. Fifield, John R. Goss
  • Patent number: 7609577
    Abstract: A design structure embodied in a machine readable medium used in a design process includes an apparatus for sensing the state of a programmable resistive memory element device, the apparatus further including a latch device coupled to a fuse node and a reference node, the fuse node included within a fuse leg and the reference node configured within a reference resistance leg, the latch device configured to detect a differential signal developed between the reference node and the fuse node as the result of sense current passed through the fuse leg and the reference resistance leg; and the fuse and reference resistance legs further configured for first and second sensing modes, wherein the second sensing mode utilizes a different level of current than the first sensing mode.
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: October 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, Gregory J. Fredeman, Toshiaki Kirihata, Alan J. Leslie, John M. Safran
  • Publication number: 20090180584
    Abstract: The invention provides a circuit that can observe data within shift registers without altering the data. The circuit includes selectors connected to the inputs and outputs of the shift registers. The selectors selectively connect the input with the output of a selected shift register to form a wiring loop for the selected shift register. A control device connected to the wiring loop uses the wiring loop to cause the data to be continually transferred from the output of the selected shift register to the input of the selected shift register and back through the selected shift register in a circular manner. The control device includes a counter used for determining the length of a selected shift register and a set of registers to store, for future use when rotating data in the shift registers, the length of each shift register. The control device also includes a data output accessible from outside the circuit.
    Type: Application
    Filed: July 18, 2008
    Publication date: July 16, 2009
    Applicant: International Business Machines Corporation
    Inventors: Darren L. Anand, John R. Goss, Peter O. Jakobsen, Michael R. Ouellette, Thomas O. Sopchak, Donald L. Wheater
  • Publication number: 20090158092
    Abstract: The status of multiple on-chip power supply systems is indicated for use in modifying chip test flow and diagnosing chip failure. Digital compliance signals are received, each compliance signal associated with one of multiple on-chip power supplies. Each power supply has an associated compliance level, and each compliance signal indicates whether its associated power supply is operating at the associated compliance level. The compliance signals are converted into a power supply status signal indicating status of the compliance signals associated with the power supply. The power supply status signal is output. If a power supply is operating at its associated compliance level, the output power supply status signal indicates that the power supply is passing. If the power supply is not operating at its associated compliance level, the output power supply status signal indicates that the power supply is failing. If a power supply is failing, a memory test may be aborted, simplifying chip failure diagnosis.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 18, 2009
    Inventors: Darren L. Anand, John A. Fifield, Kevin W. Gorman
  • Patent number: 7525831
    Abstract: A method for determining the state of a programmable resistive memory element includes passing a first level of current through a fuse leg and a reference resistance leg of a test circuit including the programmable resistive memory element; detecting a differential signal developed between a reference node and a fuse node of the test circuit as a result of the first level of current; passing a second level of current through the fuse leg and the reference leg of a test circuit, the second level of current being higher than the first level of current so as to enable detection of trip resistance of the test circuit at a lower value than with respect to the first level of current; and detecting a differential signal developed between the reference node and the fuse node of the test circuit as a result of the second level of current.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: April 28, 2009
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, Gregory J. Fredeman, Toshiaki Kirihata, Alan J. Leslie, John M. Safran
  • Publication number: 20090063896
    Abstract: A system and method for providing DRAM device-level repair via address remappings external to the device. A system includes a memory controller having an interface to one or more memory devices via a memory module. The memory devices include addressable redundant and non-redundant memory blocks. The memory controller also includes a mechanism for utilizing one or more redundant memory blocks in place of one or more failing non-redundant memory blocks via an address remapping external to the memory device. The remapping occurs while the system is on-line.
    Type: Application
    Filed: September 4, 2007
    Publication date: March 5, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Luis A. Lastras-Montano, Darren L. Anand, Jeffrey H. Dreibelbis, Charles A. Kilmer, Warren E. Maule, Robert B. Tremaine
  • Patent number: 7477555
    Abstract: A differential fuse sensing system includes a fuse leg configured for introducing a sense current through an electrically programmable fuse (eFUSE) to be sensed, and a differential sense amplifier having a first input node coupled to the fuse leg and a second node coupled to a reference voltage. The fuse leg further includes a current supply device controlled by a variable reference current generator configured to generate an output signal therefrom such that the voltage on the first input node of the sense amplifier is equal to the voltage on the second input node of the sense amplifier whenever the resistance value of the eFUSE is equal to the resistance value of a programmable variable resistance device included within the variable reference current generator.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: January 13, 2009
    Assignee: International Business Machines Corporation
    Inventors: Darren L. Anand, John A. Fifield, Michael R. Ouellette