Patents Assigned to Synopsys, Inc.
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Patent number: 6148275Abstract: An improved system or and method of connecting a hardware modeling element to the pin electronics circuitry of a hardware modeling system, with the improved system having circuitry and structures that will allow it to be connected to a hardware modeling system that is powered, circuitry to indicate to the pin electronics circuitry that the improved system is connected to it, circuitry to identify the hardware modeling element supported by the improved system to the hardware modeling system, circuitry to indicate to the hardware modeling system when the hardware modeling element is initialized so evaluation of it by the hardware modeling system can commence, circuitry to generate selectable supply voltages for the powering the hardware modeling element, and a hardware modeling element connector that will allow the connection of a family of hardware modeling elements to the same connector without the need to change the connector.Type: GrantFiled: August 28, 1997Date of Patent: November 14, 2000Assignee: Synopsys, Inc.Inventors: Mark Stanley Papamarcos, Andrew Jefferson Read, Wayne Phillip Heideman, Robert Kristianto Mardjuki, Robert Kimberly Couch, Peter Ralph Jaeger, William Fitch Kappauf, Melvin Rudin, Norman Francis Kelly, Lawrence Curtis Widdoes, Jr.
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Patent number: 6141790Abstract: A computerized method and system for automatically extracting an IEEE 1149.1 standard design from a netlist and performing compliance checking. The present invention receives the TAP (test access port) description and compliance enable ports of a netlist. The TAP controller is extracted and its state ports are identified, referenced in a boundary scan design database (BSDD) and its states are verified. The TAP controller is controlled so that the instruction register is located and referenced in the BSDD. The TAP controller is controlled so that the bypass register is found and the BSDD is updated. The TAP controller is controlled so that the shift and update cells of the boundary scan register (BSR) are found, the control, input and output BSR cells are characterized and the BSDD is updated. Primary input and output information is also inferred and the device.sub.-- ID register is found. Frontier pins are used to locate signatures of the remaining instructions and their test data registers are found.Type: GrantFiled: October 30, 1997Date of Patent: October 31, 2000Assignee: Synopsys, Inc.Inventors: James Beausang, Harbinder Singh
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Patent number: 6132109Abstract: This invention provides a method for displaying circuit analysis results corresponding to parts of the circuit near the portion of the hardware description language (HDL) specification that generated that part of the circuit. The invention also includes a method for using probe statements in the HDL specification to mark additional points in the initial circuit that should not be eliminated during optimization. This improves the ability to display circuit analysis results near the appropriate part of the HDL specification.Type: GrantFiled: June 3, 1994Date of Patent: October 17, 2000Assignee: Synopsys, Inc.Inventors: Brent Gregory, Trinanjan Chatterjee, Jing C. Lin, Srinivas Raghvendra, Emil Girczyc, Paul Estrada, Andrew Seawright
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Patent number: 6128768Abstract: A layout parasitic extraction system is disclosed. The present invention is a connectivity-based approach for extracting layout parasitics. The present invention creates a connectivity-based database, where geometries of a layout are organized by net. The present invention allows net-by-net extraction of layout parasitics using a connectivity-based database. Furthermore, a user can select a net or nets for extraction. The present invention outputs a database containing nets and their extracted layout parasitics. The present invention can create a netlist format file from a database containing nets and their extracted parasitics to allow back annotation of layout parasitics into a circuit schematic or for use for other software (possibly from a third-party).Type: GrantFiled: July 16, 1997Date of Patent: October 3, 2000Assignee: Synopsys, Inc.Inventor: William Wai Yan Ho
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Patent number: 6122643Abstract: A system and method for automated submission of an article into an electronic document system. In one embodiment, the present invention receives, in response to a web-based query form, the location of an electronic copy of an article which is desired to be submitted into an electronic document system. In the present embodiment, the article is accessible to the electronic document system. After retrieving the article, the present invention forwards the retrieved article to a universal resource locator corresponding to an article review site. At the article review site, the article is organized into a split-page format. That is, the article is organized such that electronic document system-based program code representing the displayed appearance of the article is shown on one side of the display. The article itself is displayed on the other side of the display such that the result of alterations to the electronic document system-based program code on the display appearance of the article is readily observable.Type: GrantFiled: August 25, 1997Date of Patent: September 19, 2000Assignee: Synopsys, Inc.Inventors: Young Paik, Timothy J. Malcolm, Kartik Ramakrishnan, Catherine Star-Young
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Patent number: 6106568Abstract: A system and method for architecting design for test circuitry (e.g., scan architecting) within an integrated circuit design having subdesigns (e.g., modules). The novel system contains a default operational mode (no user specification) and an operational mode based on user specifications; within either mode, the system recognizes and allows definition of subdesign scan chains which can be linked together alone or with other scan elements to architect complex scan chains (e.g., top level scan chains). The system includes specification, analysis, synthesis and reporting processes which can be used in an IC design having a hierarchical structure including modules. The specification process accesses a design database and a script file and allows a user to define global scan properties (scan style, number of chains, etc.), properties of a particular scan chain (membership, name, etc.), test signals (scan-in, scan-out, scan-enable, etc.Type: GrantFiled: June 3, 1999Date of Patent: August 22, 2000Assignee: Synopsys, Inc.Inventors: James Beausang, Chris Ellingham, Markus F. Robinson, Robert Walker
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Patent number: 6102960Abstract: A method and a system for generating a behavioral model for a device having a plurality of driver pins and receiver pins. The method and system includes connecting the plurality of driver and receiver pins to a test apparatus including an input stimulation means, a voltage measurement means, and a current measurement means, stimulating a first set of the plurality of receiver pins using the input stimulation means, performing voltage measurements at selected ones of the plurality of driver pins using the voltage measurement means, stimulating a second set of the plurality of receiver pins using the input stimulation means, performing current measurements at selected ones of the plurality of driver pins using the current measurement means, and creating the behavioral model using the voltage measurements and the current measurements.Type: GrantFiled: February 23, 1998Date of Patent: August 15, 2000Assignee: Synopsys, Inc.Inventors: Charles E. Berman, Jon N. Powell
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Patent number: 6100900Abstract: A method and apparatus for simultaneously displaying numerical data on contribution of various parts to a whole by breaking up the data into the different parts that contributed to the whole and assigning a different color to each. Then the amount of each of these parts is determined and the measurements are plotted by combining the colors into a hue, where the color of the hue represents the relative contribution of the each part for each piece of numerical data.Type: GrantFiled: December 11, 1997Date of Patent: August 8, 2000Assignee: Synopsys, Inc.Inventors: Christopher D. Rokusek, Larry Rubin
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Patent number: 6088823Abstract: A circuit for efficiently performing shadow logic testing and memory block testing within a semiconductor integrated circuit. The integrated circuit includes a memory block for storing data. A shadow logic circuit is coupled to the memory block for interfacing the memory block with external circuitry. The shadow logic provides inputs to the memory block and receives data outputs from the memory block. A test collar is coupled between the memory block and the shadow logic. The test collar receives the data inputs from the shadow logic and receives the data outputs from the memory block. The test collar is configured to both provide test inputs to the shadow logic and capture test outputs from the shadow logic independent of the memory block. The test collar is also adapted to both provide tests inputs to the memory block and capture test outputs from the memory block independent of the shadow logic.Type: GrantFiled: June 12, 1998Date of Patent: July 11, 2000Assignee: Synopsys, Inc.Inventors: Timothy Ayres, Amitava Majumdar, Ajay Khoche
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Patent number: 6075932Abstract: This is a method of quickly computing the power dissipated by a digital circuit using information available at the gate library level. It estimates the short-circuit power by modeling the energy dissipated by the cell per input transition as a function of the transition time or edge rate, and multiplying that value by the number of transitions per second for that input.Type: GrantFiled: October 14, 1997Date of Patent: June 13, 2000Assignee: Synopsys, Inc.Inventors: Adel Khouja, Shankar Krishnamoorthy, Frederic G. Mailhot, Stephen F. Meier
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Patent number: 6067650Abstract: A computer implemented process and system for effectively determining a set of sequential cells with a integrated circuit design that can be scan replaced (e.g. for design for test applications) to offer significant testability while still maintaining specified optimization (e.g., area and/or timing) constraints that are applicable to the design. The novel system selects sequential cells for scan replacement that offer best testability contribution while not selecting sequential cells for scan replacement that do not offer much testability contribution and/or are part of most critical paths within the design. The novel system is composed of a subtractive method and an additive method. The subtractive method inputs a fully scan replaced netlist (e.g., the sequential cells are scan replaced) that does not meet determined optimization constraints. The novel subtractive system unscans selected cells until the area and/or timing constraints are met. A flag indicates whether nor not timing is considered.Type: GrantFiled: December 5, 1997Date of Patent: May 23, 2000Assignee: Synopsys, Inc.Inventors: James Beausang, Kenneth Wagner, Robert Walker
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Patent number: 6059837Abstract: A method and system for an automata-based approach to state reachability of an interacting extended finite state machine. The present invention comprises a computer system having a processor, and a memory coupled to the processor via a bus, the memory containing computer readable instructions which when executed by the processor cause the processor to implement a process in accordance with the present invention. A digital system is modeled as an extended finite state machine. Automata operations are applied to the extended finite state machine to efficiently compute a set of reachable states from an initial state. The design of the system is verified by determining whether the set of reachable states includes an undesirable state.Type: GrantFiled: December 30, 1997Date of Patent: May 9, 2000Assignee: Synopsys, Inc.Inventors: James H. Kukula, Thomas R. Shiple
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Patent number: 6058252Abstract: A computer system and computer implemented method for deriving constraints with which to direct automatic integrated circuit layout is disclosed. The present invention is particularly adapted for use in the design of large integrated circuits with complex synchronous timing behavior. Preferably, the invented computer system includes means for storing a netlist data structure within a storage means is provided, the netlist data structure representing a circuit configuration having a plurality of circuit elements and representing static timing information for the circuit configuration; means for selecting specified circuit elements to be used for generating the layout constraints, whereby the specified circuit elements that are selected are fewer than, i.e.Type: GrantFiled: August 13, 1997Date of Patent: May 2, 2000Assignee: Synopsys, Inc.Inventors: Mark D. Noll, Kenneth E. Scott, Robert L. Walker
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Patent number: 6056784Abstract: 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: GrantFiled: October 3, 1997Date of Patent: May 2, 2000Assignee: Synopsys, Inc.Inventor: Robert T. Stanion
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Patent number: 6053948Abstract: A computer system including a memory model of a memory circuit. The computer system comprises a processor coupled to receive and manipulate the memory model, and a memory including the memory model. The memory model includes: a number of address bits corresponding to a number of address bits of the memory circuit; a number of data bits corresponding to a number of data bits of the memory circuit; and a memory type parameter corresponding to a type of the memory circuit.Type: GrantFiled: December 22, 1997Date of Patent: April 25, 2000Assignee: Synopsys, Inc.Inventors: Radha Vaidyanathan, Emil F. Girczyc, Sivaram Krishna Nayudu, Mahadevan Ganapathi
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Patent number: 6038381Abstract: A computer-implemented process for determining a signal function for use in controlling the application of signal operands to a circuit-implemented function for the purpose of power reduction. The present invention receives a netlist represented as a graph data structure having nodes interconnected with signal lines. A node can have one output (single fan-out) or can have more than one output (multiple fan-outs). Termination points of the graph are identified as inputs to registers or primary outputs. From the termination points, and using a breadth-first traversal process, the present invention traverses each node of the netlist. A parent node is not processed in the breadth-first traversal until all of its child nodes have been processed. During traversal, an activation signal function is constructed for each input of a node. If the node has multiple outputs then a disjunctive Boolean expression is used, otherwise a conjunctive Boolean expression is used to determine the activation signal function.Type: GrantFiled: November 25, 1997Date of Patent: March 14, 2000Assignee: Synopsys, Inc.Inventors: Michael Munch, Bernd Wurth, Renu Mehra, James David Sproch
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Patent number: 6026219Abstract: A method and an apparatus for coupling the results of behavioral synthesis with those of logic synthesis. It uses a timing verifier to precalculate the timing characteristics of a circuit for use by behavioral synthesis. Timing for control chaining is included in the precalculated timing characteristics. Once behavioral synthesis is complete, logic synthesis is informed of timing constraints introduced by behavioral synthesis.Type: GrantFiled: May 12, 1995Date of Patent: February 15, 2000Assignee: Synopsys, Inc.Inventors: Ronald A. Miller, Donald B. MacMillen, Tai A. Ly, David W. Knapp
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Patent number: 6023568Abstract: A method and an apparatus for constructing a model of a digital circuit which contains level sensitive latches. The model allows for time borrowing amongst latches. Chains of latches or latch paths are collapsed together. The resulting model can be used for simulation or synthesis.Type: GrantFiled: November 15, 1996Date of Patent: February 8, 2000Assignee: Synopsys, Inc.Inventor: Russell B. Segal
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Patent number: 6012155Abstract: A computerized method and system for automatically extracting an IEEE 1149.1 standard design from a netlist and performing compliance checking. The present invention receives the TAP (test access port) description and compliance enable ports of a netlist. The TAP controller is extracted and its state ports are identified, referenced in a boundary scan design database (BSDD) and its states are verified. The TAP controller is controlled so that the instruction register is located and referenced in the BSDD. The TAP controller is controlled so that the bypass register is found and the BSDD is updated. The TAP controller is controlled so that the shift and update cells of the boundary scan register (BSR) are found, the control, input and output BSR cells are characterized and the BSDD is updated. Primary input and output information is also inferred and the device.sub.-- ID register is found. Frontier pins are used to locate signatures of the remaining instructions and their test data registers are found.Type: GrantFiled: October 30, 1997Date of Patent: January 4, 2000Assignee: Synopsys, Inc.Inventors: James Beausang, Harbinder Singh
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Layout overlap detection with selective flattening in computer implemented integrated circuit design
Patent number: 6011911Abstract: The present invention relates to a method for efficiently performing hierarchical design rules checks (DRC) and layout versus schematic comparison (LVS) on layout areas of an integrated circuit where cells overlap or where a cell and local geometry overlap. With the present invention, a hierarchical tree describes the integrated circuit's layout data including cells having parent-child relationships and including local geometry. The present invention performs efficient layout verification by performing LVS and DRC checking on the new portions of an integrated circuit design and layout areas containing overlapping cells. When instances of cells overlap, the present invention determines the overlap area using predefined data structures that divide each cell into an array of spatial bins. Each bin of a parent is examined to determine if two or more cell instances reside therein or if a cell instance and local geometry reside therein.Type: GrantFiled: September 30, 1997Date of Patent: January 4, 2000Assignee: Synopsys, Inc.Inventors: Wai-Yan Ho, Hongbo Tang