Patents by Inventor William W. Walker

William W. Walker 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).

  • Publication number: 20090037762
    Abstract: The disaster recovery techniques, for presentment of a company's bills, statements or the like, provide electronic document presentment in the event of a disaster that impacts the company's print mail delivery operation or other existing mailing system(s). Files containing electronic documents are received, from a system associated with the print mail delivery operation, and the documents are stored in a database. Preferably, the systems use the company's existing data files. The files may be converted to a format compatible with one or more electronic delivery methodologies, if necessary. The disaster recovery systems present notice and/or data from the documents to the company's customers electronically, for example as e-mail (notice or message containing some or all of the document data), as a document attachment to an e-mail, via a web site, and possibly via telephone voice announcement.
    Type: Application
    Filed: January 3, 2003
    Publication date: February 5, 2009
    Inventors: Francesco Gozzo, Emmett M. Perry,, JR., William W. Walker, Michael J. Maselli, James N. Sutton,, JR.
  • Publication number: 20080192873
    Abstract: In one embodiment, a method includes receiving a data signal comprising a plurality of bits. The method further includes generating a clock signal. A plurality of samples is acquired from the data signal at a sampling rate determined by the clock signal and it is determined whether a transition point from a first bit in the plurality of bits to a second bit in the plurality of bits occurs within the plurality of samples. If it is determined that the transition point occurs within the plurality of samples, a state machine comprising a plurality of states transitions from a first state to a second state. If the second state indicates a non-zero amount of phase displacement between the clock signal and the data signal, the clock signal is adjusted to correlate with the data signal.
    Type: Application
    Filed: January 30, 2008
    Publication date: August 14, 2008
    Applicant: Fujitsu Limited
    Inventors: Hirotaka Tamura, Nikola Nedovic, William W. Walker
  • Publication number: 20080191770
    Abstract: In particular embodiments, an apparatus includes a first transistor connected at the gate to a first input signal voltage and a second transistor connected at the gate to a second input signal voltage. The apparatus further includes a deactivation element coupled to the transistors, the deactivation element being operable to deactivate the first and second transistors by selectively transmitting a deactivation current to a first terminal of the first transistor and a second terminal of the second transistor thereby raising a voltage on the first and second terminals to a value large enough to deactivate the first and second transistors. In particular embodiments, activating the first or second transistor transmits a signal from the apparatus and deactivating the first and second transistors prevents the signal from being transmitted from the apparatus.
    Type: Application
    Filed: December 19, 2007
    Publication date: August 14, 2008
    Applicant: Fujitsu Limited
    Inventors: Nikola Nedovic, William W. Walker
  • Patent number: 7405593
    Abstract: Disclosed are on-chip global electrical signaling systems and methods employing differential current-mode sensing having reduced delay and energy dissipation compared to conventional inverter repeaters. The present inventions can be used for point-to-point connections as well as N-to-1 connections.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: July 29, 2008
    Assignee: Fujitsu Limited
    Inventors: Nestor Tzartzanis, William W. Walker
  • Patent number: 7307483
    Abstract: Disclosed are multiphase oscillators comprising a plurality of delay stages serially coupled in a loop by a plurality of nodes, with the loop being folded to provide two concentric rings of delay stages with equal numbers of allocated nodes. A second plurality of negative-resistance elements are provided, each element having a first output coupled to a node on the first concentric ring and a second output coupled to a node on the second concentric ring. Each such output switches between first and second voltage levels, and provides a negative resistance to a signal coupled to it during at least a portion of the transition between voltage levels. The outputs of an element switch to opposite voltage levels. With this construction, a high-voltage pulse propagates around the loop of delay stages, with a low-voltage pulse propagating behind it. Also disclosed are circuits to control the direction of pulse propagation.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: December 11, 2007
    Assignee: Fujitsu Limited
    Inventors: Nestor Tzartzanis, William W. Walker
  • Patent number: 7256621
    Abstract: Disclosed are keeper circuits for electronic circuits that selectively maintain the voltage level of an intermediate circuit node at a desired level. In one exemplary embodiment, a keeper transistor either provides current or drains current from the intermediate node to maintain the desired voltage level in response to a signal to do so. The keeper circuit works against a leakage current that either drains current from the node or supplies current to the node. A current-setting transistor is coupled in series with the keeper transistor to set the maximum current through the keeper circuit to a value that is related to this leakage current, preferably tracking the leakage current. With this construction, the current-setting transistor is able to track variations in the leakage current caused by variations in the manufacturing process, and thereby provide dynamic leakage compensation.
    Type: Grant
    Filed: March 25, 2005
    Date of Patent: August 14, 2007
    Assignee: Fujitsu Limited
    Inventors: Yolin Lih, William W. Walker
  • Patent number: 7075842
    Abstract: Disclosed is a memory architecture where current sense amplifiers are used instead of voltage sense amplifiers, and where the memory cells normally disposed along a single bit line are divided between two half bit lines. Each half bit line is coupled to a respective input of the current sense amplifier. When one of the memory cells is selected for reading, it couples a current related to its stored data state to the half bit line that it is coupled to. During this operation, a reference current is generated on the other half bit line. Also disclosed are novel current sense amplifiers.
    Type: Grant
    Filed: February 13, 2004
    Date of Patent: July 11, 2006
    Assignee: Fujitsu Limited
    Inventors: Nestor Tzartzanis, William W. Walker
  • Patent number: 7027345
    Abstract: Techniques, including a system and method, are disclosed for conditionally pre-charging a memory circuit, for example a flip-flop, and thus reducing power consumption. In an embodiment a method for reducing power consumption in a memory circuit, including, a pre-charged stage coupled to an evaluation stage by at least an internal node, is provided. The method includes setting an input of the pre-charged stage to a first high logic level. Next, responsive to the setting of the input, the internal node is set to a low logic level within a first transparency window. Then responsive to the setting of the internal node, the evaluation stage changes the output of the evaluation stage to a second high logic level within the first transparency window. Lastly, when the input remains at the first high-logic level, the internal node is maintained at the low logic level through at least a second transparency window.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: April 11, 2006
    Assignee: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobd{hacek over (z)}ija, William W. Walker
  • Patent number: 6842046
    Abstract: A system and method, for converting a voltage input from a low voltage source to a voltage output at a high voltage source using a domino logic circuit design. An embodiment provides a low to high voltage conversion system. The system includes: a pull-up transistor coupled to a high voltage source for charging a node, when a precharge signal is received; a low voltage source used for setting an input voltage; a pull-down network for discharging the node depending, at least in part, on the input voltage; and an output voltage determined from the node.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: January 11, 2005
    Assignee: Fujitsu Limited
    Inventors: Nestor Tzartzanis, William W. Walker
  • Patent number: 6778466
    Abstract: An improved multi-port memory cell circuit which has a smaller number of write lines and/or transistors than conventional multi-port memory cells, and hence occupies a smaller area, is provided. The reduced area memory cell circuit includes: word lines associated with each bit line of a set of bit lines; a first word line for selecting a subset of the set of bit lines; a second word line for selecting a bit line of the subset of bit lines; and a memory cell for storing a bit value on the selected bit line.
    Type: Grant
    Filed: April 11, 2002
    Date of Patent: August 17, 2004
    Assignee: Fujitsu Limited
    Inventor: William W. Walker
  • Patent number: 6753715
    Abstract: A Symmetric Pulse Generator Flip-Flop (SPG-FF). The flip-flop comprises two pulse generator stages that each respond to one particular transition of an input clock signal. Thus, the flip-flop is triggered on both the rising and falling edge of the clock signal to capture an input data signal. The outputs of the generator stages are combined to form a flip-flop output.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: June 22, 2004
    Assignee: Fujitsu Limited
    Inventors: Volin G. Oklobdzija, William W. Walker, Nikola M. Nedovic
  • Publication number: 20040057313
    Abstract: A Symmetric Pulse Generator Flip-Flop (SPG-FF). The flip-flop comprises two pulse generator stages that each respond to one particular transition of an input clock signal. Thus, the flip-flop is triggered on both the rising and falling edge of the clock signal to capture an input data signal. The outputs of the generator stages are combined to form a flip-flop output.
    Type: Application
    Filed: September 20, 2002
    Publication date: March 25, 2004
    Inventors: Volin G. Oklobdzija, William W. Walker, Nikola M. Nedovic
  • Patent number: 6693459
    Abstract: The present invention provides techniques, including a system and method, for improving speed in a flip-flop, having a pre-charged stage coupled to an evaluation stage. In one exemplary embodiment delay is reduced by using a conditional rather than an unconditional keeper, where the conditional keeper has the function of a keeper only under certain conditions. In some embodiments there is a conditional keeper in either the pre-charged stage or the evaluation stage or both stages. Another embodiment provides for the combining of the evaluation stage with one or more external logic functions.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: February 17, 2004
    Assignee: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobd{haeck over (z)}ija, William W. Walker
  • Patent number: 6646487
    Abstract: The invention relates generally to the field of electronic circuit design, and in particular to techniques for reducing hazards in a digital logic circuit, for example, a digital logic flip-flop circuit. In an embodiment of the present invention a method for reducing hazards in a flip-flop, including, a pre-charged stage coupled to an evaluation stage by at least an internal node, is provided. First, the pre-charged stage sets the internal node based on a data input. The evaluation stage is prevented from evaluating the internal node for a predetermined time period. After the predetermined time period, the internal node is evaluated by the evaluation stage to determine an output of the flip-flop.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: November 11, 2003
    Assignee: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobd{haeck over (z)}ija, William W. Walker
  • Publication number: 20030198094
    Abstract: An improved multi-port memory cell circuit which has a smaller number of write lines and/or transistors than conventional multi-port memory cells, and hence occupies a smaller area, is provided. The reduced area memory cell circuit includes: word lines associated with each bit line of a set of bit lines; a first word line for selecting a subset of the set of bit lines; a second word line for selecting a bit line of the subset of bit lines; and a memory cell for storing a bit value on the selected bit line.
    Type: Application
    Filed: April 11, 2002
    Publication date: October 23, 2003
    Applicant: Fujitsu Limited
    Inventor: William W. Walker
  • Publication number: 20030141899
    Abstract: A system and method, for converting a voltage input from a low voltage source to a voltage output at a high voltage source using a domino logic circuit design. An embodiment provides a low to high voltage conversion system. The system includes: a pull-up transistor coupled to a high voltage source for charging a node, when a precharge signal is received; a low voltage source used for setting an input voltage; a pull-down network for discharging the node depending, at least in part, on the input voltage; and an output voltage determined from the node.
    Type: Application
    Filed: January 31, 2002
    Publication date: July 31, 2003
    Applicant: Fujitsu Limited
    Inventors: Nestor Tzartzanis, William W. Walker
  • Publication number: 20030062940
    Abstract: The invention relates generally to the field of electronic circuit design, and in particular to techniques for reducing hazards in a digital logic circuit, for example, a digital logic flip-flop circuit. In an embodiment of the present invention a method for reducing hazards in a flip-flop, including, a pre-charged stage coupled to an evaluation stage by at least an internal node, is provided. First, the pre-charged stage sets the internal node based on a data input. The evaluation stage is prevented from evaluating the internal node for a predetermined time period. After the predetermined time period, the internal node is evaluated by the evaluation stage to determine an output of the flip-flop.
    Type: Application
    Filed: January 11, 2002
    Publication date: April 3, 2003
    Applicant: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobdzija, William W. Walker
  • Publication number: 20030062925
    Abstract: The present invention provides techniques, including a system and method, for improving speed in a flip-flop, having a pre-charged stage coupled to an evaluation stage. In one exemplary embodiment delay is reduced by using a conditional rather than an unconditional keeper, where the conditional keeper has the function of a keeper only under certain conditions. In some embodiments there is a conditional keeper in either the pre-charged stage or the evaluation stage or both stages. Another embodiment provides for the combining of the evaluation stage with one or more external logic functions.
    Type: Application
    Filed: January 11, 2002
    Publication date: April 3, 2003
    Applicant: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobdzija, William W. Walker
  • Publication number: 20030056129
    Abstract: Techniques, including a system and method, are disclosed for conditionally pre-charging a memory circuit, for example a flip-flop, and thus reducing power consumption. In an embodiment a method for reducing power consumption in a memory circuit, including, a pre-charged stage coupled to an evaluation stage by at least an internal node, is provided. The method includes setting an input of the pre-charged stage to a first high logic level. Next, responsive to the setting of the input, the internal node is set to a low logic level within a first transparency window. Then responsive to the setting of the internal node, the evaluation stage changes the output of the evaluation stage to a second high logic level within the first transparency window. Lastly, when the input remains at the first high-logic level, the internal node is maintained at the low logic level through at least a second transparency window.
    Type: Application
    Filed: January 11, 2002
    Publication date: March 20, 2003
    Applicant: Fujitsu Limited
    Inventors: Nikola Nedovic, Vojin G. Oklobdzija, William W. Walker
  • Patent number: 5987641
    Abstract: A wrist pad is provided including a flexible removable wrap with a top extent and a bottom extent. At least one sleeve is mounted on the bottom extent of the wrap. A rigid element includes at least one portion defining a periphery of a cylinder and a sphere. Such rigid element is removably situated within the sleeve during use.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: November 23, 1999
    Inventor: William W. Walker