Patents by Inventor John E. Mahoney

John E. Mahoney 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: 5995988
    Abstract: An apparatus for loading configuration information into a programmable integrated circuit (e.g., an FPGA) configurable to perform parallel loading or bit serial loading within the same architecture. The configuration information is presented to the FPGA in data frames of N serial bits each. Each data frame is divided into discrete serial portions having Y bits each (e.g., a data frame comprises N/Y portions). In parallel mode, the portions are loaded into a segmented configuration register, one portion per programming cycle, such that Y bits are loaded into the segmented configuration register in parallel. On each programming clock cycle during parallel loading, all the bits of a data frame portion are simultaneously loaded into the segments of the configuration register (at the first bit position for each segment) such that each segment receives one bit per programming cycle. The bits of the configuration register are then shifted down by one and the cycle repeats for the next data frame portion.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: November 30, 1999
    Assignee: Xilinx, Inc.
    Inventors: Philip M. Freidin, Stephen M. Trimberger, John E. Mahoney, Charles R. Erickson
  • Patent number: 5961576
    Abstract: An apparatus for loading configuration information into a programmable integrated circuit (e.g., an FPGA) configurable to perform parallel loading or bit serial loading within the same architecture. The configuration information is presented to the FPGA in data frames of N serial bits each. Each data frame is divided into discrete serial portions having Y bits each (e.g., a data frame comprises N/Y portions). In parallel mode, the portions are loaded into a segmented configuration register, one portion per programming cycle, such that Y bits are loaded into the segmented configuration register in parallel. On each programming clock cycle during parallel loading, all the bits of a data frame portion are simultaneously loaded into the segments of the configuration register (at the first bit position for each segment) such that each segment receives one bit per programming cycle. The bits of the configuration register are then shifted down by one and the cycle repeats for the next data frame portion.
    Type: Grant
    Filed: October 22, 1998
    Date of Patent: October 5, 1999
    Assignee: Xilinx, Inc.
    Inventors: Philip M. Freidin, Stephen M. Trimberger, John E. Mahoney, Charles R. Erickson
  • Patent number: 5844829
    Abstract: An apparatus for loading configuration information into a programmable integrated circuit (e.g., an FPGA) configurable to perform parallel loading or bit serial loading within the same architecture. The configuration information is presented to the FPGA in data frames of N serial bits each. Each data frame is divided into discrete serial portions having Y bits each (e.g., a data frame comprises N/Y portions). In parallel mode, the portions are loaded into a segmented configuration register, one portion per programming cycle, such that Y bits are loaded into the segmented configuration register in parallel. On each programming clock cycle during parallel loading, all the bits of a data frame portion are simultaneously loaded into the segments of the configuration register (at the first bit position for each segment) such that each segment receives one bit per programming cycle. The bits of the configuration register are then shifted down by one and the cycle repeats for the next data frame portion.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: December 1, 1998
    Assignee: Xilinx, Inc
    Inventors: Philip M. Freidin, Stephen M. Trimberger, John E. Mahoney, Charles R. Erickson
  • Patent number: 5742531
    Abstract: An apparatus for loading configuration information into a programmable integrated circuit (e.g., an FPGA) configurable to perform parallel loading or bit serial loading within the same architecture. The configuration information is presented to the FPGA in data frames of N serial bits each. Each data frame is divided into discrete serial portions having Y bits each (e.g., a data frame comprises N/Y portions). In parallel mode, the portions are loaded into a segmented configuration register, one portion per programming cycle, such that Y bits are loaded into the segmented configuration register in parallel. On each programming clock cycle during parallel loading, all the bits of a data frame portion are simultaneously loaded into the segments of the configuration register (at the first bit position for each segment) such that each segment receives one bit per programming cycle. The bits of the configuration register are then shifted down by one and the cycle repeats for the next data frame portion.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: April 21, 1998
    Inventors: Philip M. Freidin, Stephen M. Trimberger, John E. Mahoney, Charles R. Erickson
  • Patent number: 5712579
    Abstract: A clock distribution network and mechanisms therein for an integrated circuit (IC) including an edge clock and distribution system for same. The invention includes a deskewed clock distribution network for circuits situated in columns wherein buffering is done in columns less than half of the IC length. The mechanism allows each of at least eight vertical column distribution lines to couple with any horizontal clock supply line of at least eight lines. The horizontal clock supply lines include local interconnect inputs. To increase clock source signals, special lines, Kx lines, are provided that are buffered and traverse directionally in 1/4 IC lengths from the top down, bottom up, and midsection both up and down. Kx lines can be sourced from carry signals, IOBs, interconnects, or from an edge clock and supply to clock lines, longlines, or interconnect lines. Kx lines allow vertical signal displacement, e.g., for clock signals, etc., within the chip.
    Type: Grant
    Filed: October 16, 1995
    Date of Patent: January 27, 1998
    Assignee: Xilinx, Inc.
    Inventors: Khue Duong, Stephen M. Trimberger, Robert O. Conn, Jr., John E. Mahoney
  • Patent number: 5694056
    Abstract: A pipeline frame full detection circuit. The present invention is operable within a system that loads configuration data into an integrated circuit (IC) using a serial data stream and transfer mechanism. Configuration data is transferred into the IC in sequential frames of a specified size for a given IC. The first bit of the configuration data contains a frame full indicator. The configuration data is transferred into a shift register circuit and the last bit position(s) of the shift register circuit, in addition to being stored in the shift register circuit, are shifted along a special frame full pipeline to a control unit. The control unit, upon detecting the frame full indicator, asserts a parallel write command that causes the data of the shift register circuit to be parallel transferred to a receiving column of memory. New configuration data can then be serially shifted into the same shift register circuit after a reset signal.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: December 2, 1997
    Assignee: Xilinx, Inc.
    Inventors: John E. Mahoney, Stephen M. Trimberger, Charles R. Erickson
  • Patent number: 5367207
    Abstract: This invention provides a structure and method for interconnecting logic devices through line segments which can be joined by programming antifuses. One of several programming lines can be connected through an interconnect line segment to each terminal of each antifuse in the array. Interconnect line segments connected to opposite terminals of the same antifuse are connected to a different programming line in order to be able to apply different voltages to the two terminals of the antifuse. An addressing structure selectively connects interconnect line segments to their respective programming lines, and programming voltages applied to the programming lines cause a selected antifuse to be programmed. A novel addressing feature sequentially addresses two transistors for the line segments to be connected, and takes advantage of a capacitive pumped decoder to maintain the addressed transistors turned on while programming voltages are applied.
    Type: Grant
    Filed: December 4, 1990
    Date of Patent: November 22, 1994
    Assignee: Xilinx, Inc.
    Inventors: F. Erich Goetting, David B. Parlour, John E. Mahoney
  • Patent number: 5234092
    Abstract: A control valve mechanism has concentric spool valve members that are selectively positionable to provide control pressure. The control pressure may be used for the selective actuation of fluid operated friction torque transmitting devices, such as clutches and brakes, in a power transmission.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: August 10, 1993
    Assignee: General Motors Corporation
    Inventor: John E. Mahoney
  • Patent number: 5155432
    Abstract: The integrity of a circuit processing logic signals is verified by use of switching means, including pass transistors, which are selectively varied to provide different test circuit configurations for different modes of operation. The circuit operates in normal, scan, test and data receive modes. During normal operation, the logic signal from the primary circuit is passed directly through a logic test block without the shifting of data in the logic test block.
    Type: Grant
    Filed: July 16, 1991
    Date of Patent: October 13, 1992
    Assignee: Xilinx, Inc.
    Inventor: John E. Mahoney
  • Patent number: 5068603
    Abstract: A structure and method for producing mask-configured integrated circuits which are pin compatible substitutes for user-configured logic arrays is disclosed. Mask-defined routing lines having resistive/capacitive characteristics simulating those of user-configurable routing paths in the user-configurable logic array are used in the mask-defined substitutes to replace the user-configurable routing paths. Scan testing networks are formed in the metal-configured substitutes to test the operability of logical function blocks formed on such chips. The scan testing networks comprise a plurality of test blocks each including three field effect pass transistors formed of four adjacent diffusion regions. Proper connection of the gates of these pass transistors to control lines controlling the transistors is tested by transmitting alternating high/low signals through serial conduction paths including the gate electrodes of these transistors.
    Type: Grant
    Filed: May 15, 1989
    Date of Patent: November 26, 1991
    Assignee: Xilinx, Inc.
    Inventor: John E. Mahoney
  • Patent number: 5047710
    Abstract: The integrity of a circuit processing logic signals is verified by use of switching means, including pass transistors, which are selectively varied to provide different test circuit configurations for different modes of operation. The circuit operates in normal, scan, test and data receive modes. During normal operation, the logic signal from the primary circuit is passed directly through a logic test block without the shifting of data in the logic test block.
    Type: Grant
    Filed: July 26, 1989
    Date of Patent: September 10, 1991
    Assignee: Xilinx, Inc.
    Inventor: John E. Mahoney
  • Patent number: 4855669
    Abstract: The integrity of a circuit processing logic signals is verified by use of switching means, including pass transistors, which are selectively varied to provide different test circuit configurations for different modes of operation. The circuit operates in normal, scan, test and data receive modes. During normal operation, the logic signal from the primary circuit is passed directly through a logic test block without the shifting of data in the logic test block.
    Type: Grant
    Filed: October 7, 1987
    Date of Patent: August 8, 1989
    Assignee: Xilinx, Inc.
    Inventor: John E. Mahoney
  • Patent number: 4805752
    Abstract: A fluid operated friction torque transmitting device has an apply piston disposed in a housing. An apply chamber having a predetermined area is formed on one side of the piston, and an opposing or compensating chamber of lesser area is formed on the other side of the piston. A torque transmitting shaft and an inner hub portion of the housing cooperate to form a rotary valve member which is operable to connect the apply chamber to high fluid pressure and the opposing chamber to low fluid pressure, when torque is transmitted from the input side of the transmitter to the output side of the transmitter; and to connect both the apply chamber and the opposing chamber to high fluid pressure when torque is being transmitted from the output side of the transmitter to the input side of the transmitter.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: February 21, 1989
    Assignee: General Motors Corporation
    Inventors: John D. Malloy, John E. Mahoney
  • Patent number: 4610177
    Abstract: A preselected multiratio transmission has three selectively engageable input friction clutches and three selectively engageable synchronized mechanical ratio clutches. The friction clutches are connected with respective input shafts each of which shafts has two input ratio gears rotatably mounted thereon and one of the synchronized clutches connected therewith. Each synchronized clutch is operable to control two gear ratios. A countershaft has a plurality of output ratio gears connected therewith, which gears mesh with respective ones of the input ratio gears. The countershaft is drivingly connected with a transmission output means. The synchronized clutches are operated to preselect a drive ratio which is then completed by the engagement of the friction clutch associated therewith and the substantially simultaneous disengagement of either of the other friction clutches which may have been engaged.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: September 9, 1986
    Assignee: General Motors Corporation
    Inventor: John E. Mahoney