Patents by Inventor Daniel M. Nelson

Daniel M. 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: 9142560
    Abstract: A semiconductor chip has shapes on a particular level that are small enough to require a first mask and a second mask, the first mask and the second mask used in separate exposures during processing. A circuit on the semiconductor chip requires close tracking between a first and a second FET (field effect transistor). For example, the particular level may be a gate shape level. Separate exposures of gate shapes using the first mask and the second mask will result in poorer FET tracking (e.g., gate length, threshold voltage) than for FETs having gate shapes defined by only the first mask. FET tracking is selectively improved by laying out a circuit such that selective FETs are defined by the first mask. In particular, static random access memory (SRAM) design benefits from close tracking of six or more FETs in an SRAM cell.
    Type: Grant
    Filed: August 18, 2014
    Date of Patent: September 22, 2015
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Publication number: 20150262667
    Abstract: An apparatus includes a hit bitline driver circuit and an equalization control circuit. The hit bitline driver circuit may be configured to drive a pair of hit bitlines responsive to a search bit. The equalization control circuit may be configured to transfer charge from one hit bitline of the pair to the other hit bitline of the pair in response to the search bit changing state.
    Type: Application
    Filed: April 14, 2014
    Publication date: September 17, 2015
    Applicant: LSI CORPORATION
    Inventors: TRAVIS HEBIG, CHRISTOHPER D. BROWNING, ERIC W. EKLUND, DANIEL M. NELSON, RICHARD J. STEPHANI
  • Publication number: 20140353764
    Abstract: A semiconductor chip has shapes on a particular level that are small enough to require a first mask and a second mask, the first mask and the second mask used in separate exposures during processing. A circuit on the semiconductor chip requires close tracking between a first and a second FET (field effect transistor). For example, the particular level may be a gate shape level. Separate exposures of gate shapes using the first mask and the second mask will result in poorer FET tracking (e.g., gate length, threshold voltage) than for FETs having gate shapes defined by only the first mask. FET tracking is selectively improved by laying out a circuit such that selective FETs are defined by the first mask. In particular, static random access memory (SRAM) design benefits from close tracking of six or more FETs in an SRAM cell.
    Type: Application
    Filed: August 18, 2014
    Publication date: December 4, 2014
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Patent number: 8824196
    Abstract: A static random access memory (SRAM) includes a column of SRAM memory cells. The SRAM may include a circuit to copy a value stored in any SRAM memory cell in a column of SRAM memory cells to any SRAM memory cell in the column of SRAM memory cells in a single cycle of the SRAM.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: September 2, 2014
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Patent number: 8711606
    Abstract: A circuit and method erase at power-up all data stored in a DRAM chip for increased data security. All the DRAM memory cells are erased by turning on the transistors for the DRAM storage cells simultaneously by increasing the body voltage of cells. In the example circuit, the body voltage is increased by a charge pump controlled by a power-on-reset (POR) signal applying a voltage to the p-well of the memory cells. The added voltage to the p-well lowers the threshold voltage of the cell, such that the NFET transistor of the memory cell will turn on. With all the devices turned on, the data stored in the memory cells is erased as the voltage of all the cells connected to a common bitline coalesce to a single value.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: April 29, 2014
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Patent number: 8675427
    Abstract: A method and circuit for implementing delay correction in static random access memory (SRAM), and a design structure on which the subject circuit resides are provided. The SRAM circuit includes a precharge enable signal coupled between precharge near and precharge far signals and wordline near and wordline far signals of the SRAM. A precharge pull down device is coupled between the precharge far signal and ground and is controlled responsive to the precharge enable signal to decrease a time delay of the falling transition of the precharge far signal. A respective word line pull up device is coupled between a respective wordline far signal and a voltage supply rail and is controlled responsive to the precharge enable signal to increase wordline voltage level upon a rising transition of the wordline far signal.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: March 18, 2014
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Publication number: 20130258758
    Abstract: A static random access memory (SRAM) includes a column of SRAM memory cells. The SRAM may include a circuit to copy a value stored in any SRAM memory cell in a column of SRAM memory cells to any SRAM memory cell in the column of SRAM memory cells in a single cycle of the SRAM.
    Type: Application
    Filed: March 30, 2012
    Publication date: October 3, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Publication number: 20130235681
    Abstract: A method and circuit for implementing delay correction in static random access memory (SRAM), and a design structure on which the subject circuit resides are provided. The SRAM circuit includes a precharge enable signal coupled between precharge near and precharge far signals and wordline near and wordline far signals of the SRAM. A precharge pull down device is coupled between the precharge far signal and ground and is controlled responsive to the precharge enable signal to decrease a time delay of the falling transition of the precharge far signal. A respective word line pull up device is coupled between a respective wordline far signal and a voltage supply rail and is controlled responsive to the precharge enable signal to increase wordline voltage level upon a rising transition of the wordline far signal.
    Type: Application
    Filed: March 7, 2012
    Publication date: September 12, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Patent number: 8520429
    Abstract: A semiconductor chip has an SRAM (static random access memory). The SRAM includes a data dependent write assist circuit which, on writes, reduces a supply voltage on one of a cross coupled inverter pair in an SRAM cell, thereby making it easier to overcome the one of the cross coupled inverters.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: August 27, 2013
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Publication number: 20130175631
    Abstract: A semiconductor chip has shapes on a particular level that are small enough to require a first mask and a second mask, the first mask and the second mask used in separate exposures during processing. A circuit on the semiconductor chip requires close tracking between a first and a second FET (field effect transistor). For example, the particular level may be a gate shape level. Separate exposures of gate shapes using the first mask and the second mask will result in poorer FET tracking (e.g., gate length, threshold voltage) than for FETs having gate shapes defined by only the first mask. FET tracking is selectively improved by laying out a circuit such that selective FETs are defined by the first mask. In particular, static random access memory (SRAM) design benefits from close tracking of six or more FETs in an SRAM cell.
    Type: Application
    Filed: January 6, 2012
    Publication date: July 11, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Patent number: 8395963
    Abstract: A circuit and method erase at power-up all data stored in a DRAM chip for increased data security. All the DRAM memory cells are erased by turning on the transistors for the DRAM storage cells simultaneously by driving the wordlines of all the cells to an activated state. With all the devices turned on, the data stored in the memory cells is erased as the voltage of all the cells connected to a common bitline coalesce to a single value. In a preferred embodiment, the wordlines are all turned on simultaneously during a power on reset period. Preferably a power on reset signal is used to drive each logic gate of the pre-decoder portion of the address decoder in order to assert all the wordlines.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: March 12, 2013
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson
  • Patent number: 8344782
    Abstract: A delay circuit receives a data input having an input transition and that generates a data output having an output transition. The delay circuit is powered by a voltage source having a voltage. A first delay element is configured to generate a first data signal with a first edge that has a relatively constant delay relative to the input transition irrespective of the voltage of the voltage source. A second delay element is configured to generate a second data signal with a second edge that has a delay relative to the input transition as a function of the voltage of the voltage source. A selection element causes the output transition at the data output to correspond to a latest selected one of the first edge and the second edge. The delay circuit may be employed in a pulse generating circuit.
    Type: Grant
    Filed: November 6, 2009
    Date of Patent: January 1, 2013
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson
  • Publication number: 20120281457
    Abstract: A semiconductor chip has an SRAM (static random access memory). The SRAM includes a data dependent write assist circuit which, on writes, reduces a supply voltage on one of a cross coupled inverter pair in an SRAM cell, thereby making it easier to overcome the one of the cross coupled inverters.
    Type: Application
    Filed: May 5, 2011
    Publication date: November 8, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Michael Launsbach, Daniel M. Nelson
  • Publication number: 20120147661
    Abstract: A circuit and method erase at power-up all data stored in a DRAM chip for increased data security. All the DRAM memory cells are erased by turning on the transistors for the DRAM storage cells simultaneously by driving the wordlines of all the cells to an activated state. With all the devices turned on, the data stored in the memory cells is erased as the voltage of all the cells connected to a common bitline coalesce to a single value. In a preferred embodiment, the wordlines are all turned on simultaneously during a power on reset period. Preferably a power on reset signal is used to drive each logic gate of the pre-decoder portion of the address decoder in order to assert all the wordlines.
    Type: Application
    Filed: December 9, 2010
    Publication date: June 14, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson
  • Publication number: 20110280088
    Abstract: A reduced bitline precharge level has been found to increase the SRAM Beta ratio, thus improving the stability margin. The precharge level is also supplied to Sense amplifier, write driver, and source voltages for control signals. In the sense amplifier, the lower precharge voltage compensates for performance loss in the bit-cell by operating global data-line drivers with increased overdrive. In the write driver, the reduced voltage improves the Bitline discharge rate, improves the efficiency of the negative boost write assist, and decreases the reliability exposure of transistors in the write path from negative boost circuit.
    Type: Application
    Filed: May 13, 2010
    Publication date: November 17, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: CHAD A. ADAMS, GEORGE M. BRACERAS, DANIEL M. NELSON, HAROLD PILO, VINOD RAMADURAI
  • Patent number: 7971164
    Abstract: A system, method and program product are described in which schematics in a library that a user has tagged are read as ready for layout. The difficulty of each layout is assessed based on statistics indicative of the complexity of the schematic. The statistics may regard the number of connections, pins, devices, and other schematic information. The information is used to calculate the total amount of effort required to complete the design and generate a report.
    Type: Grant
    Filed: April 10, 2008
    Date of Patent: June 28, 2011
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Travis R. Hebig, Daniel M. Nelson, Jesse D. Smith
  • Publication number: 20110109366
    Abstract: A delay circuit receives a data input having an input transition and that generates a data output having an output transition. The delay circuit is powered by a voltage source having a voltage. A first delay element is configured to generate a first data signal with a first edge that has a relatively constant delay relative to the input transition irrespective of the voltage of the voltage source. A second delay element is configured to generate a second data signal with a second edge that has a delay relative to the input transition as a function of the voltage of the voltage source. A selection element causes the output transition at the data output to correspond to a latest selected one of the first edge and the second edge. The delay circuit may be employed in a pulse generating circuit.
    Type: Application
    Filed: November 6, 2009
    Publication date: May 12, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson
  • Patent number: 7714630
    Abstract: The present disclosure is an apparatus for generating a decreasing delay with increasing input voltage to a predetermined voltage value at which point the delay may remain constant. The apparatus may include a circuit comprising a voltage regulator receiving an input voltage and two paths of inverters. At least two paths of inverters may be coupled to an input signal, the input signal may be low voltage (e.g. 0) or high voltage (e.g. 1). A first path may be referenced to a reference voltage while the second path may be referenced to the input voltage. The apparatus may include logic gates for receiving the output of each of the first path of inverters and the output of the second path of inverters to generate a desired output. As the input voltage increases, delay of the apparatus may decrease until the input voltage is approximately the same voltage as the reference voltage, at which the delay may remain constant.
    Type: Grant
    Filed: June 13, 2008
    Date of Patent: May 11, 2010
    Assignee: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson
  • Publication number: 20100030804
    Abstract: Embodiments of the invention provide techniques for synchronizing virtual locations to real locations. In one embodiment, data sources are monitored to detect events that affect real locations. A filter specified by an owner of the virtual location may be used to detect keywords indicating events affecting a particular location. In the event that such events are detected, the owner may be notified to modify the virtual location to match the real location. Optionally, the virtual location may be automatically modified to match the real location.
    Type: Application
    Filed: July 31, 2008
    Publication date: February 4, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derick G. Behrends, Zachary A. Garbow, Travis R. Hebig, Daniel M. Nelson, Jesse D. Smith
  • Publication number: 20090309644
    Abstract: The present disclosure is an apparatus for generating a decreasing delay with increasing input voltage to a predetermined voltage value at which point the delay may remain constant. The apparatus may include a circuit comprising a voltage regulator receiving an input voltage and two paths of inverters. At least two paths of inverters may be coupled to an input signal, the input signal may be low voltage (e.g. 0) or high voltage (e.g. 1). A first path may be referenced to a reference voltage while the second path may be referenced to the input voltage. The apparatus may include logic gates for receiving the output of each of the first path of inverters and the output of the second path of inverters to generate a desired output. As the input voltage increases, delay of the apparatus may decrease until the input voltage is approximately the same voltage as the reference voltage, at which the delay may remain constant.
    Type: Application
    Filed: June 13, 2008
    Publication date: December 17, 2009
    Applicant: International Business Machines Corporation
    Inventors: Derick G. Behrends, Todd A. Christensen, Travis R. Hebig, Daniel M. Nelson