Patents Represented by Attorney Scott R. Brown
  • Patent number: 7627291
    Abstract: An integrated circuit operable to wirelessly communicate with other devices by utilizing a radio transceiver and a routing element is disclosed. The routing element is operable to route a signal between various circuit elements and is selectively operable to function as an antenna when coupled with the radio transceiver.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: December 1, 2009
    Assignee: XILINX, Inc.
    Inventors: Philip B. James-Roxby, Daniel J. Downs
  • Patent number: 7620883
    Abstract: SEU mitigation, detection, and correction techniques are disclosed. Mitigation techniques include: triple redundancy of a logic path extended the length of the FPGA; triple logic module and feedback redundancy provides redundant voter circuits at redundant logic outputs and voter circuits in feedback loops; enhanced triple device redundancy using three FPGAs is introduced to provide nine instances of the user's logic; critical redundant outputs are wire-ANDed together; redundant dual port RAMs, with one port dedicated to refreshing data; and redundant clock delay locked loops (DLL) are monitored and reset if each DLL does not remain in phase with the majority of the DLLs. Detection techniques include: configuration memory readback wherein a checksum is verified; separate FPGAs perform readbacks of configuration memory of a neighbor FPGA; and an FPGA performs a self-readback of its configuration memory array.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: November 17, 2009
    Assignee: XILINX, Inc.
    Inventors: Carl H. Carmichael, Phil Edward Brinkley, Jr.
  • Patent number: 7370294
    Abstract: A low-leakage circuit design method involves determining a capacity of a power gating transistor using delay statistics, wherein the resulting power gating transistor has sufficient capacity to supply all of the current necessary to meet the demands of the powered design elements while minimizing an amount of chip space required to implement the power gating transistor. The capacity of the power gating transistor is determined by first estimating a capacity necessary to meet the demands of all design elements connected to the transistor. The design elements are then grouped according to input signal arrival time to determine an amount by which the estimated capacity of the gating transistor may be reduced without affecting operation of the design elements. Various grouping schemes are evaluated to determine an optimal grouping. The estimated transistor capacity is reduced according to the optimal grouping, and the power gating transistor is implemented accordingly.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: May 6, 2008
    Assignee: Xilinx, Inc.
    Inventor: Arifur Rahman
  • Patent number: 7310759
    Abstract: SEU mitigation, detection, and correction techniques are disclosed. Mitigation techniques include: triple redundancy of a logic path extended the length of the FPGA; triple logic module and feedback redundancy provides redundant voter circuits at redundant logic outputs and voter circuits in feedback loops; enhanced triple device redundancy using three FPGAs is introduced to provide nine instances of the user's logic; critical redundant outputs are wire-ANDed together; redundant dual port RAMs, with one port dedicated to refreshing data; and redundant clock delay locked loops (DLL) are monitored and reset if each DLL does not remain in phase with the majority of the DLLs. Detection techniques include: configuration memory readback wherein a checksum is verified; separate FPGAs perform readbacks of configuration memory of a neighbor FPGA; and an FPGA performs a self-readback of its configuration memory array.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: December 18, 2007
    Assignee: Xilinx, Inc.
    Inventors: Carl H. Carmichael, Phil Edward Brinkley, Jr.
  • Patent number: 7310794
    Abstract: A computer-readable medium is encoded with a computer program for directing a computer to convert a first bitstream operable to configure, for example, an earlier-generation PLD to a second bitstream operable to configure, for example, a later-generation PLD, wherein functionality is preserved from one PLD to another. The computer divides each PLD into similar regions, and replicates a function of each region of the first PLD in a corresponding region of the second PLD. The computer interconnects the regions of the second PLD to replicate the interconnections of the regions of the first PLD. The computer allows a user to manipulate the connection scheme of the second PLD.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: December 18, 2007
    Assignee: Xilinx, Inc.
    Inventor: David B. Squires
  • Patent number: 7298175
    Abstract: An integrated circuit programmable multiplexer that reduces sub-threshold leakage current in deep sub-micron technology. The multiplexer uses a plurality of transistor stages, wherein each transistor of a subsequent stage is connected to at least two transistors of a prior stage, such that each transistor is in series with at least one other transistor. Transistors that are not part of the signal path through the multiplexer are deactivated, wherein a series of two or more deactivated transistors have significantly less sub-threshold leakage current than a single deactivated transistor. Configuration memory cells that store and communicate control signals to the multiplexer transistors are also connected to a low-voltage power supply when the multiplexer is not in use to reduce leakage current through the memory cells.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: November 20, 2007
    Assignee: Xilinx, Inc.
    Inventor: Arifur Rahman
  • Patent number: 7269724
    Abstract: A method and apparatus are provided for updating or changing configuration data stored in the PROM of a target system, the data being used to configure one or more reprogrammable logic devices such as FPGAs. In one embodiment the apparatus comprises a modem used to communicate remotely with a host system, a shadow PROM for receiving new configuration data intended for use in a target system, an interface for relaying configuration data from the shadow PROM to the target, and means for controlling the components of the update system.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: September 11, 2007
    Assignee: Xilinx, Inc.
    Inventors: Stephen M. Trimberger, Robert O. Conn
  • Patent number: 7036059
    Abstract: SEU mitigation, detection, and correction techniques are disclosed.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: April 25, 2006
    Assignee: Xilinx, Inc.
    Inventors: Carl H. Carmichael, Phil Edward Brinkley, Jr.
  • Patent number: 6980030
    Abstract: Integrated circuits are disclosed that have interconnected programmable logic, and configuration memory. The interconnected programmable logic is connected by a logical interconnection network. The integrated circuits have a configurable function unit including a function unit component, such as a counter or shift register. The integrated circuits further include a configurable decoder, which decodes a value presented by the function unit component based on decoder configuration data. The integrated circuits also have at least one decoder output, which provides information about a comparison of the decoder configuration data with the value presented by the function unit component.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: December 27, 2005
    Assignee: Xilinx, Inc.
    Inventors: Frank C. Wirtz, II, John R. Hubbard, Jeffrey H. Seltzer, Schuyler E. Shimanek
  • Patent number: 6914449
    Abstract: A technique for reducing leakage current in static CMOS devices by adding additional transistors in series between selected inverters or logic gates and ground or power. NMOS and PMOS transistors are added to selected buffers comprised of two inverters in series. The PMOS transistor is connected between the first inverter and power and the NMOS transistor is connected between the second inverter and ground. The added transistors are controlled by a memory cell to be on when the buffer is being used and off when the buffer is unused. Alternatively, no PMOS transistor is added and an existing PMOS transistor of the first inverter is manufactured to sit in a Vgg well. The same techniques are employed with selected buffer pairs and logic gates.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: July 5, 2005
    Assignee: Xilinx, Inc.
    Inventor: Alireza S. Kaviani
  • Patent number: 6774668
    Abstract: A programmable integrated circuit is disclosed that includes a nonvolatile memory cell programmed to represent a configuration bit associated with a special purpose function. A volatile memory cell is associated with the nonvolatile memory cell. The integrated circuit includes a logic gate for logically combining states of the volatile and nonvolatile memory cells to selectively enable the special purpose function, even before the volatile memory cell is initialized. In this way, the predetermined function can be executed prior to a complete initialization of the integrated circuit.
    Type: Grant
    Filed: January 8, 2003
    Date of Patent: August 10, 2004
    Assignee: Xilinx Inc.
    Inventor: Frank C. Wirtz, II
  • Patent number: 6711063
    Abstract: An EEPROM memory cell array architecture (50) that substantially eliminates leakage current to allow for reading memory cells (20) in a memory cell array of, for example, a CPLD at lower voltages than are possible with prior art architectures, thereby facilitating development of low voltage applications. This is accomplished by associating each wordline of the memory cell array with a ground transistor (26). On one embodiment, the ground transistor (26) can be a high voltage transistor, in which case the same high voltage control signal can control both the ground transistor (26) and the memory cell=s read transistor (32). In another embodiment, the ground transistor (26) is a low voltage transistor controlled by a separate low voltage control signal.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: March 23, 2004
    Assignee: Xilinx, Inc.
    Inventors: Anders T. Dejenfelt, David Kuan-Yu Liu
  • Patent number: 6657447
    Abstract: A chemical mixture of liquid crystal and a substance that lowers the clear/opaque transition temperature of the liquid crystal, thins the liquid crystal, and makes the liquid crystal more sensitive to heat generated in the lower layers of an integrated circuit chip during IC hot spot testing. The substance can be a solvent or a diluent comprising a ketone or an alcohol.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: December 2, 2003
    Assignee: Xilnx, Inc.
    Inventor: Seyed Amir David Parandoosh
  • Patent number: 6593779
    Abstract: The present invention provides a tunable circuit for quickly optimizing an electrical field generated by the F-N tunneling operation. To optimize this electrical field, the charging of a positive charge pump is begun after the charging of a negative charge pump. The tunable circuit of the present invention provides a means to detect the optimal negative voltage at which pumping of the positive voltage should begin. The tunable circuit includes a resistor chain coupled between a first reference voltage and a negative voltage from the negative charge pump. When charging of the negative charge pump begins, a comparator compares the voltage at a node within the resistor chain to a second reference voltage. In accordance with the present invention, the node voltage within the resistor chain is equal to the second reference voltage when the negative voltage is equal to the voltage to be detected. Thus, the comparator generates a trigger signal when the voltage at the node decreases to the second reference voltage.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: July 15, 2003
    Assignee: Xilinx, Inc.
    Inventors: Farshid Shokouhi, Ben Y. Sheen, Qi Lin
  • Patent number: 6583645
    Abstract: An FPGA is described using optical waveguides for routing signals through the FPGA. The routing is controlled electrically. Either coupling waveguides or resonant disks can be used for routing the optical signals. Lookup tables convert optical input signals to electrical signals for selecting values in the lookup table.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: June 24, 2003
    Assignee: Xilinx, Inc.
    Inventors: David W. Bennett, Sundararajarao Mohan, Ralph D. Wittig
  • Patent number: 6569576
    Abstract: A reticle and pellicle that are modified to prevent ESD damage to the masking material between portions of the lithographic mask pattern on the reticle during an integrated circuit fabrication process. The modification involves providing conducting lines on the glass side of the reticle and on the surface of the pellicle to balance any buildup of electrostatic charges on those devices, thereby reducing or eliminating the induction of opposite charges onto adjacent mask pattern features on the reticle and preventing the melting and bridging of those mask pattern features and the defects caused by such melting or bridging. The conductive metal lines may have a smaller width than the smallest resolution value of the reduction lens used in the mask pattern transfer process, and may also be located outside of the focal plane of the reduction lens to avoid transfer of the images of the conductive lines onto the target semiconductor substrate during the mask pattern transfer process.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: May 27, 2003
    Assignee: Xilinx, Inc.
    Inventors: Shih-Cheng Hsueh, Kevin T. Look, Jonathan Jung-Ching Ho
  • Patent number: 6559715
    Abstract: A low pass filter (LPF) is provided that smoothes and significantly slows any change in its input voltage. The capacitance of the LPF is provided by an NMOS transistor having its source and drain tied to ground. The resistance of the LPF is provided by a plurality of series-connected PMOS transistors. The gates of the PMOS transistors are coupled to ground and therefore these transistors are conducting. The PMOS transistors are fabricated in a floating well. Therefore, the LPF eliminates any capacitive coupling between a voltage supply and the well. Thus, any variation in the supply voltage fails to affect adversely the functioning of the PMOS transistors. Thus, the LPF of the present invention can advantageously smooth and significantly slow any change in its input voltage. In one embodiment, the input voltage is a reference voltage.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: May 6, 2003
    Assignee: Xilinx, Inc.
    Inventors: Scott O. Frake, Jason R. Bergendahl
  • Patent number: 6525565
    Abstract: Method and apparatus for doubling the throughput rate of data transmission on a logic path comprising providing two latches that alternately receive successive bits of the data stream to be transmitted and a multiplexer having data transmission paths that are alternately clocked by two separate clocks, which clocks are substantially 180 degrees out of phase.
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: February 25, 2003
    Assignee: Xilinx, Inc.
    Inventors: Steven P. Young, Suresh M. Menon, Ketan Sodha, Richard A. Carberry, Joseph H. Hassoun
  • Patent number: 6507205
    Abstract: A tester to device-under-test interface is disclosed in which a PCB has a socket for a device under test (DUT), one or more cable connectors for cables from an IC tester, an interface matrix card slot having a plurality of contacts electrically connected to the DUT socket and the cable connector pins, and an interface matrix card having a plurality of horizontal and vertical conductors capable of being electrically connected to each other for mapping the proper connection of signals between the DUT socket and the tester cables.
    Type: Grant
    Filed: November 14, 2000
    Date of Patent: January 14, 2003
    Assignee: Xilinx, Inc.
    Inventors: Michael J. Dibish, Sunae Kang
  • Patent number: 6493862
    Abstract: An FPGA architecture and method to reduce the size of the bitstream used in configuring or reconfiguring the FPGA. To facilitate features of the compression process, an FPGA is modified to implement an addressable data register in place of a conventional shift register. This allows data frames to be arranged in order of similarity, and a bitstream formed from one full data frame along with an address into which the frame is to be loaded, and subsequent partial data frames including only changed words along with the row address of the changes and the column address into which modified frames are to be loaded, rather than shifting in entire frames of data for subsequent frames.
    Type: Grant
    Filed: July 25, 2000
    Date of Patent: December 10, 2002
    Assignee: Xilinx Inc.
    Inventors: Steven P. Young, Jeffrey V. Lindholm