Patents by Inventor David C. Lawson

David C. Lawson 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: 9288055
    Abstract: Methods and systems are provided for verifying use of encryption keys. A request for verification information may be sent by a network element (e.g., server), with the request comprising combination of one or more identifiers, the combination associated with a particular I/O operation. The request may be sent to another element, which may be a centralized encryption management element (e.g., management server). In response to the request, key use verification information generated for the particular I/O operation may be received, and may be used thereafter in validating a corresponding encryption key, which may be used during data encryption or decryption, based on the received key use verification information and locally generated verification information associated with the particular I/O operation. The one or more identifiers include at least one of a target identifier, a LUN identifier, and a LBA range identifier.
    Type: Grant
    Filed: February 26, 2015
    Date of Patent: March 15, 2016
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: John Sui-kei Tang, Larry Dean Hofer, David C. Lawson
  • Publication number: 20150180668
    Abstract: Methods and systems are provided for verifying use of encryption keys. A request for verification information may be sent by a network element (e.g., server), with the request comprising combination of one or more identifiers, the combination associated with a particular I/O operation. The request may be sent to another element, which may be a centralized encryption management element (e.g., management server). In response to the request, key use verification information generated for the particular I/O operation may be received, and may be used thereafter in validating a corresponding encryption key, which may be used during data encryption or decryption, based on the received key use verification information and locally generated verification information associated with the particular I/O operation. The one or more identifiers include at least one of a target identifier, a LUN identifier, and a LBA range identifier.
    Type: Application
    Filed: February 26, 2015
    Publication date: June 25, 2015
    Inventors: John Sui-kei Tang, Larry Dean Hofer, David C. Lawson
  • Patent number: 8411490
    Abstract: A sense amplifier for static random access memories is disclosed. The sense amplifier includes a pair of inverters cross-coupled to each other. The sense amplifier also includes means for equalizing the charges within the pair of inverters before performing a sense operation, and means for sensing a current difference between a bitline and its complement from a memory cell during the sense operation.
    Type: Grant
    Filed: July 10, 2004
    Date of Patent: April 2, 2013
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventors: David C. Lawson, Edward Maher, Shankarnarayana Ramaswamy, Tri Minh Hoang
  • Patent number: 8189367
    Abstract: A single event upset (SEU) hardened memory cell to be utilized in static random access memories is disclosed. The SEU hardened memory cell includes a first transistor, a second transistor and a first resistor connected between a source of the first transistor and a drain of the second transistor. The SEU hardened memory cell also includes a third transistor, a fourth transistor and a second resistor connected between a source of the third transistor and a drain of the fourth transistor. The first resistor is also connected between a gate of the third transistor and the drain of the second transistor. The second resistor is also connected between a gate of the first transistor and the drain of the fourth transistor.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: May 29, 2012
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventors: David C. Lawson, Jason F. Ross
  • Publication number: 20120120704
    Abstract: A single event upset (SEU) hardened memory cell to be utilized in static random access memories is disclosed. The SEU hardened memory cell includes a first transistor, a second transistor and a first resistor connected between a source of the first transistor and a drain of the second transistor. The SEU hardened memory cell also includes a third transistor, a fourth transistor and a second resistor connected between a source of the third transistor and a drain of the fourth transistor. The first resistor is also connected between a gate of the third transistor and the drain of a the second transistor. The second resistor is also connected between a gate of a the first transistor and the drain of the fourth transistor.
    Type: Application
    Filed: February 8, 2008
    Publication date: May 17, 2012
    Inventors: David C. Lawson, Jason F. Ross
  • Publication number: 20100079183
    Abstract: Tri-stating transistors which are controlled by the latch enable lines isolate holding transistors from the latch node during setting of the latch. The tri-stating transistors are connected to the holding transistors and the latch node which allows the node to float and assume a third state during setting of the latch when the latch is enabled.
    Type: Application
    Filed: September 30, 2008
    Publication date: April 1, 2010
    Applicant: BAE SYSTEMS INFORMATION AND ELECTRONIC SYSTEMS INTEGRATION INC.
    Inventors: David C. Lawson, Michael A. Belzecky
  • Patent number: 7468904
    Abstract: A single event upset (SEU) hardened memory cell to be utilized in static random access memories is disclosed. The SEU hardened memory cell includes a first inverter and a second inverter connected to each other in a cross-coupled manner. The SEU hardened memory cell also includes a first resistor, a second resistor and a capacitor. The first resistor is connected between an input of the first inverter and an output of the second inverter. The second resistor is connected between an input of the second inverter and an output of the first inverter. The capacitor is connected between an input of the first inverter and an input of the second inverter.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: December 23, 2008
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventors: David C. Lawson, Jason Ross
  • Publication number: 20080205112
    Abstract: A single event upset (SEU) hardened memory cell to be utilized in static random access memories is disclosed. The SEU hardened memory cell includes a first inverter and a second inverter connected to each other in a cross-coupled manner. The SEU hardened memory cell also includes a first resistor, a second resistor and a capacitor. The first resistor is connected between an input of the first inverter and an output of the second inverter. The second resistor is connected between an input of the second inverter and an output of the first inverter. The capacitor is connected between an input of the first inverter and an input of the second inverter.
    Type: Application
    Filed: February 23, 2007
    Publication date: August 28, 2008
    Inventors: David C. Lawson, Jason Ross
  • Patent number: 7307948
    Abstract: A system comprising a host system, a driver in communication with a host system, and a plurality of host bus adapters in communication with the driver. The host bus adapters provide a plurality of data transmission paths between the host system and a storage device. The driver is operable to adjust data transmission loads between the paths without burdening the operating system.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: December 11, 2007
    Assignee: Emulex Design & Manufacturing Corporation
    Inventors: Jon L. Infante, Mark J. Karnowski, Christopher Carlin, David C. Lawson
  • Patent number: 7099187
    Abstract: A read/write circuit for accessing chalcogenide non-volatile memory cells is disclosed. The read/write circuit includes a chalcogenide storage element, a voltage limiting circuit, a current-to-voltage converter, and a buffer circuit. The voltage limiting circuit, which is coupled to the chalcogenide storage element, ensures that voltages across the chalcogenide storage element will not exceed a predetermined value during a read operation. During a read operation, the current-to-voltage converter, which is coupled to the voltage limiting circuit, converts a current pulse read from the chalcogenide storage element to a voltage pulse. By sensing the voltage pulse from the current-to-voltage converter, the buffer circuit can determine a storage state of the chalcogenide storage element.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: August 29, 2006
    Assignees: BAE Systems Information and Electronic Systems Integration Inc., Ovonyx, Inc.
    Inventors: Bin Li, Kenneth R. Knowles, David C. Lawson
  • Patent number: 6965521
    Abstract: A read/write circuit for accessing chalcogenide non-volatile memory cells is disclosed. The read/write circuit includes a chalcogenide storage element, a voltage limiting circuit, a current-to-voltage converter, and a buffer circuit. The voltage limiting circuit, which is coupled to the chalcogenide storage element, ensures that voltages across the chalcogenide storage element will not exceed a predetermined value during a read operation. During a read operation, the current-to-voltage converter, which is coupled to the voltage limiting circuit, converts a current pulse read from the chalcogenide storage element to a voltage pulse. By sensing the voltage pulse from the current-to-voltage converter, the buffer circuit can determine a storage state of the chalcogenide storage element.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: November 15, 2005
    Assignee: BAE Systems, Information and Electronics Systems Integration, Inc.
    Inventors: Bin Li, Kenneth R. Knowles, David C. Lawson
  • Patent number: 6944041
    Abstract: A circuit for accessing a chalcogenide memory array is disclosed. The chalcogenide memory array includes multiple subarrays with rows and columns formed by chalcogenide storage elements. The chalcogenide memory array is accessed by discrete read and write circuits. Associated with a respective one of the subarrays, each of the write circuits includes an independent write 0 circuit and an independent write 1 circuit. Also associated with a respective one of the subarrays, each of the read circuits includes a sense amplifier circuit. In addition, a voltage level control module is coupled to the read and write circuits to ensure that voltages across the chalcogenide storage elements within the chalcogenide memory array do not exceed a predetermined value during read and write operations.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: September 13, 2005
    Assignee: BAE Systems Information and Electronic Systems Integration, Inc.
    Inventors: Bin Li, Kenneth R. Knowles, David C. Lawson
  • Publication number: 20040078632
    Abstract: A system comprising a host system, a driver in communication with a host system, and a plurality of host bus adapters in communication with the driver. The host bus adapters provide a plurality of data transmission paths between the host system and a storage device. The driver is operable to adjust data transmission loads between the paths without burdening the operating system.
    Type: Application
    Filed: October 21, 2002
    Publication date: April 22, 2004
    Inventors: Jon L. Infante, Mark J. Karnowski, Christopher Carlin, David C. Lawson
  • Patent number: 6327176
    Abstract: A single event upset hardened latch circuit is disclosed. The single event hardened latch circuit includes a first dual-port inverter and a second dual-port inverter. An input is coupled to the first dual-port inverter via a first set of pass gates. The first dual-port inverter is coupled to the second dual-port inverter via a second set of pass gates. The output is connected to the first and second dual-port inverters.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: December 4, 2001
    Assignees: Systems Integration Inc., BAE Systems Information and Electronic
    Inventors: Bin Li, David C. Lawson
  • Patent number: 6301179
    Abstract: In a sense amplifier for reading out memory cells of a memory comprising a set of P-FETs and N-FETs, complementary input signals received from the memory cell being read out are applied to input junctions connected to gates of N-FETs. The input junctions are charged to 0.8 volts by a precharging circuit comprising P-FETs connecting the input junctions to ground and an N-FET shunting the input junctions together. The P-FETs and N-FETs of the precharging circuit are rendered conductive between memory cells readouts to precharge the input junctions and are rendered nonconducting during memory cell readouts. A second precharging circuit precharges an output junction of the sense amplifier circuit. The output junction is connected to an output amplification stage including a CMOS circuit. Because of the low equalization voltage to which the input junctions are precharged, the time to precharge the input junctions is dramatically reduced and a reduction in the memory access time is achieved.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: October 9, 2001
    Assignee: BAE Systems Information and Electronic Systems Integration, Inc.
    Inventor: David C. Lawson
  • Patent number: 6215694
    Abstract: A single event upset hardened multiport memory cell to be utilized in a register file is disclosed. The single event upset hardened multiport memory cell includes a storage cell, a write bitline, a read bitline. The storage cell, which is utilized for storing data, includes first and second sets of cross-coupled transistors and first and second sets of isolation transistors. The first and second sets of isolation transistors are respectively coupled to the first and second set of cross-coupled transistors such that two inversion paths are formed between the two sets of cross-coupled transistors and the two sets of isolation transistors. Coupled to the storage cell, the write bitline inputs write data to the storage cell. Also coupled to the storage cell, the read bitline outputs read data from the storage cell.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: April 10, 2001
    Assignee: Lockheed Martin Corporation
    Inventors: Bin Li, Livia L. Zien, David C. Lawson, Tatia B. Butts, Tri M. Hoang