Patents by Inventor Anders A. Johnson

Anders A. Johnson 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: 5920223
    Abstract: The present invention provides a method and apparatus for improving immunity to common mode noise. The present invention prevents common mode noise from exceeding acceptable limits. The present invention is also useful to prevent common mode noise from being converted to differential mode noise by the action of parasitic diodes. One embodiment of the present invention bleeds charge off two differential lines such that the relative voltage differential is maintained, for example during a memory read, until at least one of the lines is low enough that the maximum possible upward noise (common+differential) is insufficient to turn on the parasitic diodes coupled to the positive voltage supply, leaving enough margin on the differential signal to allow a sensing circuit to accurately sense the differential signal.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: July 6, 1999
    Assignee: Xilinx, Inc.
    Inventor: Robert Anders Johnson
  • Patent number: 5784313
    Abstract: A programmable logic device (PLD) comprises at least one configurable element, and a plurality of programmable logic elements for configuring the configurable element(s). Alternatively, a PLD comprises an interconnect structure and a plurality of programmable logic elements for configuring the interconnect structure. In either embodiment, at least one of the programmable logic elements includes N memory cells. A predetermined one of the N memory cells forms part of a memory slice, wherein at least a portion of each slice of the programmable logic device is allocated to either configuration data or user data memory. Typically, one memory slice provides one configuration of the programmable logic device. In accordance with one embodiment, a memory access port is coupled between at least one of the N memory cells and either one configurable element or the interconnect, thereby facilitating loading of new configuration data into other memory slices during the one configuration.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: July 21, 1998
    Assignee: Xilinx, Inc.
    Inventors: Stephen M. Trimberger, Richard A. Carberry, Robert Anders Johnson, Jennifer Wong
  • Patent number: 5778439
    Abstract: In accordance with the present invention, a programmable array includes hierarchical configuration and state storage. The array comprises an active storage for an active configuration and an active state as well as an inactive storage for one or more inactive configurations and one or more inactive states. The array further comprises logic and routing configured by the active configuration. The logic includes a plurality of combinational elements and a plurality of sequential logic elements for providing the states. Bits are transferred between the active and the inactive storage.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: July 7, 1998
    Assignee: Xilinx, Inc.
    Inventors: Stephen M. Trimberger, Richard A. Carberry, Robert Anders Johnson, Jennifer Wong
  • Patent number: 5646903
    Abstract: A DRAM memory having shared read/write lines. The DRAM memory is comprised of an array of 3T memory cells. Data is digitally stored in the form of capacitors that are either charged or discharged. Horizontal data lines are used to convey data bits to be stored in the array of memory cells. Vertical read/write lines are used to perform both read and write functions. Activating a single read/write line causes a bit of data from a memory cell to be placed onto a corresponding data line. Simultaneously, an inverted copy of that data bit is stored in an adjacent memory cell. Hence, instead of having a separate read line and a separate word line for each memory cell, the present invention has a dual function read/write word line.
    Type: Grant
    Filed: March 6, 1996
    Date of Patent: July 8, 1997
    Assignee: Xilinx, Inc.
    Inventor: R. Anders Johnson
  • Patent number: 5646545
    Abstract: A programmable logic device (PLD) comprises a plurality of configurable logic blocks (CLBs), an interconnect structure for interconnecting the CLBs, and a plurality of programmable logic elements for configuring the CLBs and the interconnect structure. Each CLB includes a combinational element and a sequential logic element, wherein at least one programmable logic element includes a plurality of memory cells for configuring the combinational element and at least one programmable logic element includes a plurality of memory cells for configuring the sequential logic element. A micro register, which stores a plurality of intermediate states of one CLB or interconnect structure, is located at the output of a CLB, the input of a CLB, or elsewhere in the interconnect structure. The PLD includes means for disabling access to at least one of said plurality of memory elements. In one embodiment, the memory cells are RAM cells, whereas in other embodiments the memory cells are ROM cells, or a combination thereof.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: July 8, 1997
    Assignee: Xilinx, Inc.
    Inventors: Stephen M. Trimberger, Richard A. Carberry, Robert Anders Johnson, Jennifer Wong
  • Patent number: 4144308
    Abstract: Liquid materials which are difficult to crystallize and which may be subject to supercooling are solidified and crystallized by contacting the liquid material with an agitated, fluidized bed of solid particles of the same material. The bed of solid particles is agitated by means of a mechanical agitator and a current of fluidizing and cooling gas which enters the bottom portion of the bed vertically but is baffled toward the periphery of the bed.
    Type: Grant
    Filed: January 3, 1977
    Date of Patent: March 13, 1979
    Assignee: Monsanto Company
    Inventor: Anders A. Johnson
  • Patent number: 4022820
    Abstract: Liquid materials which are difficult to crystallize and which may be subject to supercooling are solidified and crystallized by contacting the liquid material with an agitated, fluidized bed of solid particles of the same material. The bed of solid particles is agitated by means of a mechanical agitator and a current of fluidizing and cooling gas which enters the bottom portion of the bed vertically but is baffled toward the periphery of the bed.
    Type: Grant
    Filed: November 12, 1974
    Date of Patent: May 10, 1977
    Assignee: Monsanto Company
    Inventor: Anders A. Johnson