Patents Represented by Attorney, Agent or Law Firm Jeanette S. Harms
  • Patent number: 6707396
    Abstract: A data processing system having a device for processing data bits in parallel to generate bit-stuffed data, bit-unstuffed data, Non-Return-to-Zero-Inverted (NRZI) encoded data or NRZI-decoded data. The data processing system has a system clock operating at a system clock rate S. The device includes a data processing device and a local clock operating at a local clock rate L. The data processing device has a data storage element and a processing circuit and operates at the local clock rate L. The data storage element receives a number of bits N, where N is defined by the relation N=S/L. The processing circuit also generates N processed data bits.
    Type: Grant
    Filed: March 1, 2001
    Date of Patent: March 16, 2004
    Assignee: Synopsys, Inc.
    Inventor: Ravikumar Govindaraman
  • Patent number: 6704921
    Abstract: An automated phase assignment method is described that allows multiple rules for defining phase shifters to be used within a single cell. The rules for defining phase shifters can be sequenced. Then for a cell, the rules can be recursively applied. At each stage if the number of phase conflicts is below a threshold, then portions of the cell having conflicts are masked and processed using the next less aggressive rule set. This in turn leads to phase shifting masks with greater variation in phase shifter shapes and sizes. When the mask is used to fabricate integrated circuits (ICs), the resulting IC may have a greater number of small transistors and other features than a mask defined using only a single rule set per cell. Additional benefits can include better process latitude during IC fabrication and improved yield.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: March 9, 2004
    Assignee: Numerical Technologies, Inc.
    Inventor: Hua-Yu Liu
  • Patent number: 6704878
    Abstract: In an IC chip, a novel precomputation architecture and process which grants improved reductions in power dissipation, requires less logic to implement, and relaxes critical timing constraints. A first computation circuit is used to calculate output values if precomputation cannot be performed. However, if the output values can be precomputed, a second circuit is used to calculate the output values. The second computation circuit is smaller, simpler, and consumes less power than the first computation circuit. An extremely small and simple decision circuit, which dissipates a minimal amount of power, is used to determine whether precomputation is possible. This determination is made at a previous cycle, whereas the actual computation of the output cycles are postponed to be performed in a subsequent cycle.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: March 9, 2004
    Assignee: Synopsys, Inc.
    Inventors: Luca Benini, James Sproch, Bernd Wurth
  • Patent number: 6704697
    Abstract: A modeling method to improve the accuracy of timing analysis that more closely models timing information associated with layout parasitics that are connected to interface pins of a transistor-level subcircuit. A method is described for performing a hierarchical timing analysis of a circuit having a transistor-level subcircuit. Certain data (e.g., the layout parasitic data associated with interface nodes) associated with the transistor-level subcircuit are set aside. A timing model (timing arcs) of the transistor-level subcircuit is created without using these data. The timing analysis of the circuit is performed using a circuit analyzer. The circuit analyzer uses the timing model (timing arcs) and the layout parasitic data for the transistor-level subcircuit in the timing analysis. Thus, the layout parasitic data associated with the lower level subcircuit is preserved and used in the higher level circuit timing analysis to provide an accurate non-linear timing analysis of the layout parasitics.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: March 9, 2004
    Assignee: Synopsys, Inc.
    Inventors: Paul Berevoescu, Oleg Levitsky
  • Patent number: 6691212
    Abstract: The data from a plurality of primary data sources, such as disk drives or disk arrays, are interleaved and captured in a secondary data source, such as a tape drive, during a backup operation. The interleaving of data allows the overlap of read/write operations performed by the plurality of primary data sources, thereby optimizing the performance of the backup as well as the restore.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: February 10, 2004
    Assignee: Mirapoint, Inc.
    Inventors: Daniel D. McNeil, Joseph L. DiMartino, Jaspal Kohli
  • Patent number: 6684382
    Abstract: A method and apparatus for providing correction for microloading effects is described. Hybrid proximity correction techniques are used to make the problem computationally more feasible. More specifically, feature edges in a layout can be grouped into those edges, or edge segments, with a large edge separation (group B), e.g. greater than n, and those having less than that separation (group A). The group B features can then be corrected for microloading effects rapidly using rules based correction. Then both groups of edges can be corrected using model based optical proximity correction using the output of the rule based correction as the ideal, or reference, layout.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: January 27, 2004
    Assignee: Numerical Technologies, Inc.
    Inventor: Hua-Yu Liu
  • Patent number: 6684308
    Abstract: A method for backing up data in a computer system from a plurality of primary data sources to a secondary data source is provided. The method comprises copying data sections from the plurality of primary data sources to the secondary data source and providing a data pointer on the secondary data source. The data pointer indicates a starting point of each transfer from the plurality of primary data sources and where that starting point is on the secondary data source. This data pointer information provides the minimum information necessary to map a location from the primary data source(s) to its location on the secondary data source.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: January 27, 2004
    Assignee: Mirapoint, Inc.
    Inventor: Daniel D. McNeil
  • Patent number: 6677779
    Abstract: A control interface, which includes both master and slave devices, can provide buffering of input data packets, thereby allowing configurations of the integrated circuit to be modified quickly and efficiently. Additionally, the control interface can be sized and configured to receive digital signals from any number of nodes on an integrated circuit, thereby facilitating the testing, lab characterization, and debugging of those nodes. Finally, the control interface can advatageously control the monitoring of analog components on the integrated circuit, thereby significantly reducing the number of pins for such monitoring. The control interface has particular relevance to highly integrated circuits that utilize analog and/or mixed signals.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: January 13, 2004
    Assignee: Atheros Communications, Inc.
    Inventors: David Kuochieh Su, Masoud Zargari, Lars E. Thon, William J. McFarland
  • Patent number: 6678644
    Abstract: Integrated circuit models having associated timing and tag information therewith for use with electronic design automation to effectively model timing exception information. The present invention includes a circuit block model which allows automated circuit optimization to be performed on extremely large circuits without the need to load all of the details of the circuit into computer memory. The circuit models of the present invention effectively model timing including timing exception information. The model of the present invention is associated with command information, e.g., textual commands, that describe tags (which model exceptions) and arrival and required times associated with the tags. Specifically, for the input pins of a circuit to be modeled, the present invention writes out a command defining each unique required tag associated with an input pin and also writes out commands associating each required tag with its input pin.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: January 13, 2004
    Assignee: Synopsys, Inc.
    Inventor: Russell B. Segal
  • Patent number: 6675305
    Abstract: A method and system for selectively providing a gated clock signal to a control and status register block is provided. The method performs an operation by an application on a CSR block is provided. The operation may be programming a control register or reading a status register. The application detects when the operation is needed. If the operation is to be performed, a gated clock signal is enabled to the control and status register. The application then performs the operation on the control and status register block based on the gated clock signal. The gated clock signal may disabled after the operation has been performed. A system is provided for performing an operation on a control and status register block in a universal serial bus peripheral is provided. Clock gating logic detects when the operation is to be performed and provides a gated clock signal to the control and status register block when the operation is to be performed.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: January 6, 2004
    Assignee: Synopsys, Inc.
    Inventor: Saleem Chisty Mohammad
  • Patent number: 6670082
    Abstract: An accurate, cost-effective system and method for correcting 3D effects on an alternating phase-shifting mask (PSM) is provided. To facilitate this correction, a library can be built to include a first group of 180 degree phase-shifting regions, wherein these regions have a common first size. Based on this first size, 3D simulation is performed. A transmission and a phase are altered in a 2D simulation based on this first size until a shape dependent transmission and a shape dependent phase allow the 2D simulation to substantially match the 3D simulation. Finally, a modified first size is chosen using the shape dependent transmission and the shape dependent phase such that a 2D simulation based on the modified first size substantially matches the 3D simulation based on the first size. The library associates the first size with the modified first size, the shape dependent transmission, and the shape dependent phase.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: December 30, 2003
    Assignee: Numerical Technologies, Inc.
    Inventors: Yong Liu, Hua-Yu Liu
  • Patent number: 6671859
    Abstract: A computer implemented process for automatic creation of integrated circuit (IC) geometry using a computer. The present invention includes a general unconstrained non-linear optimization method to generate coarse placement of cells on a 2-dimensional silicon chip or circuit board. In one embodiment, the coarse placer can also be used to automatically size cells, insert and size buffers, and aid in timing driven structuring of the placed circuit. The coarse placer is used in conjunction with other automatic design tools such as a detailed placer and an automatic wire router. A master objective function (MOF) is defined which evaluates a particular cell placement. A non-linear optimization process finds an assignment of values to the function variables which minimizes the MOF. The MOF is a weighted sum of functions which evaluate various metrics. An important metric for consideration is the density metric, which measures how well spread out the cells are in the placement.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: December 30, 2003
    Assignee: Synopsys, Inc.
    Inventors: William C. Naylor, Ross Donelly, Lu Sha
  • Patent number: 6668362
    Abstract: A method and apparatus for determining equivalence between two integrated circuit device designs. Functional blocks and compare points within a first design are compared with functional blocks and compare points in a second design to determine compare points that are matched. The integrated circuit designs are traversed net-wise and cut points are inserted at compare points that are matched and that are not determined to be constant. As each design is traversed, the design is flattened such that flat copies of both integrated circuit designs are obtained (that include the inserted cut points). The flat copies of the integrated circuit designs are then compared to determine equivalence.
    Type: Grant
    Filed: January 9, 2002
    Date of Patent: December 23, 2003
    Assignee: Synopsys, Inc.
    Inventors: Lisa McIlwain, Demosthenes Anastasakis, Slawomir Pilarski
  • Patent number: 6665844
    Abstract: The invented method addresses two important issues concerning don't cares in formal system or circuit synthesis verification. First, it is shown how to represent explicit don't cares in linear space in a flattened hierarchy. Many circuits need this information for verification, but the classical calculation can be exponential. Second, three interpretations of verification on incompletely specified circuits are explored and it is shown how the invented method makes it easy to test each interpretation. The invented method involves transforming each cell within an original circuit that implements an incompletely specified function into set of plural cells that implement the upper and lower bound of the interval of the function. The method thus constructs networks for the endpoints of the intervals and, rather than constructing traditional miters, connects the outputs of the interval circuits with the logic appropriate for the property, e.g. equality or consistency, that is to be verified.
    Type: Grant
    Filed: May 1, 2000
    Date of Patent: December 16, 2003
    Assignee: Synopsys, Inc.
    Inventor: Robert T. Stanion
  • Patent number: 6665851
    Abstract: A method and system for the quick placement of electronic circuits using orthogonal one dimensional placements. All circuits of a design may be placed in a linear dimension to obtain a first placement. Next, those same circuits may be placed in a second linear dimension, orthogonal to the first dimension, in order to obtain a second placement. Finally, a two dimensional placement for the circuits may be created by selecting for each circuit element a first coordinate from the first placement and a second coordinate from the second placement.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: December 16, 2003
    Assignee: Synopsys, Inc.
    Inventors: Ross A. Donelly, William C. Naylor
  • Patent number: 6664009
    Abstract: Phase shifting layouts and masks with phase conflicts are described. The phase shifting layout defines light transmissive regions for use in defining selected features in a layer of material of an integrated circuit (IC). The phase shifting layout includes a phase conflict caused by two light transmissive regions that are out of phase with each other and which, without correction, would lead to the definition of an artifact in the layer of material. A corresponding mask adapted for use in conjunction with the phase shifting mask can ensure that the artifact is ultimately erased. The phase conflict is intentionally introduced into the phase shifting layout during phase assignment to permit all of the selected features to be defined using the phase shifting mask.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: December 16, 2003
    Assignee: Numerical Technologies, Inc.
    Inventor: Hua-Yu Liu
  • Patent number: 6665856
    Abstract: Techniques for forming a fabrication layout, such as a mask, for a physical design layout, such as a layout for an integrated circuit, include correcting the fabrication layout for proximity effects using a proximity effects model. A proximity effects model is executed to produce an initial output. The initial output is based on a first position for a segment in a fabrication layout. The first position is displaced from a corresponding original edge in the original fabrication layout by a distance equal to an initial bias. The model is also executed to produce a second output based on a second position for the segment. The second position is displaced from the corresponding original edge by a distance equal to a second bias. An optimal bias for the segment is determined based on the initial output and the second output. The segment is displaced in the fabrication layout from the corresponding edge based on the optimal bias.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: December 16, 2003
    Assignee: Numerical Technologies, Inc.
    Inventors: Christophe Pierrat, Youping Zhang
  • Patent number: 6662348
    Abstract: A computer implemented process for automatic creation of integrated circuit (IC) geometry using a computer. The present invention includes a general unconstrained non-linear optimization method to generate coarse placement of cells on a 2-dimensional silicon chip or circuit board. In one embodiment, the coarse placer can also be used to automatically size cells, insert and size buffers, and aid in timing driven structuring of the placed circuit. The coarse placer is used in conjunction with other automatic design tools such as a detailed placer and an automatic wire router. A master objective function (MOF) is defined which evaluates a particular cell placement. A non-linear optimization process finds an assignment of values to the function variables which minimizes the MOF. The MOF is a weighted sum of functions which evaluate various metrics. An important metric for consideration is the density metric, which measures how well, spread out the cells are in the placement.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: December 9, 2003
    Assignee: Synopsys, Inc.
    Inventors: William C. Naylor, Ross Donelly, Lu Sha
  • Patent number: 6658640
    Abstract: A method of optimizing a wafer fabrication process for a given mask is provided. The method includes capturing an image of a mask and simulating a wafer image of the mask. A mask map of information can then be generated based on the simulated wafer image. The resulting mask map can be provided to any downstream wafer fabrication process when such process involves the mask. One or more one input parameters to the downstream wafer fabrication process can be changed based on the mask map, thereby optimizing the process for the given mask.
    Type: Grant
    Filed: December 26, 2001
    Date of Patent: December 2, 2003
    Assignee: Numerical Technologies, Inc.
    Inventor: J. Tracy Weed
  • Patent number: 6653026
    Abstract: A structure and method are provided for correcting the optical proximity effects on a tri-tone attenuated phase-shifting mask. An attenuated rim, formed by an opaque region and an attenuated phase-shifting region, can be kept at a predetermined width across the mask or for certain types of structures. Typically, the attenuated rim is made as large as possible to maximize the effect of the attenuated phase-shifting region while still preventing the printing of larger portions of the attenuated phase-shifting region during the development process.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: November 25, 2003
    Assignee: Numerical Technologies, Inc.
    Inventors: Christophe Pierrat, Youping Zhang