Circuit Simulation Patents (Class 703/14)
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Publication number: 20090102470Abstract: A simulation apparatus according to an embodiment performs an electromagnetic field circuit coupling analysis on a first substrate and a second substrate electrically coupled via a circuit element having a finite delay time. A first coupling analysis unit carries out a time domain electromagnetic field analysis and also a circuit analysis on a circuit element at a first analytical domain including the first substrate. The second coupling analysis unit carries out a time domain electromagnetic field analysis and also a circuit analysis on a circuit element at a second analytical domain including the second substrate.Type: ApplicationFiled: October 15, 2008Publication date: April 23, 2009Applicant: SHARP KABUSHIKI KAISHAInventor: Tatsuroh KISO
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Publication number: 20090106009Abstract: Systems and media for reconstructing data from simulation models are disclosed. Embodiments may include a media containing instructions for accessing an alias from an alias file. The media may include instructions for searching for a net name and, if the net name is not found, searching an alias index file for an alias index entry associated with the net name, the alias index entry having a net name and an associated position. The instructions may also include, if the net name entry is found, instructions for accessing from an alias file an alias associated with the net name. A further embodiment may include instructions for receiving a net name and a position of an alias in the alias file, creating an alias index entry for the alias having a net name and the position of the alias, and storing the created alias index entry in the alias index file.Type: ApplicationFiled: January 2, 2009Publication date: April 23, 2009Applicant: International Business Machines CorporationInventors: Charles Lenier Alley, Anthony Joseph Bybell
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Patent number: 7523029Abstract: Logic verification is performed based on correspondence information and compile information. The correspondence information specifies information on pairs of fragments of descriptions to be compared for equivalence in a behavioral level description written in a programming language and an RT level description obtained through behavioral synthesis and information on pairs of signals to be compared for each of the description pairs. The compile information includes mapping information between the behavioral level description and an object code. A logic cone extraction section extracts first logic cones from the object code through symbolic simulation by referencing the correspondence information and the compile information. The logic cone extraction section extracts second logic cones from the RT level description. A logic cone comparison section verifies equivalence between the first and second logic cones.Type: GrantFiled: July 3, 2003Date of Patent: April 21, 2009Assignee: Nec CorporationInventor: Takashi Takenaka
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Patent number: 7523030Abstract: Disclosed is a simulation system for displaying source lines in a behavior level description during execution of simulation to indicate the execution status of a conditional branch statement in a state, including a simulation model generation unit, a simulator and a simulation monitor. The simulation model generation unit receives a source file including a behavior level description composed of a plurality of lines and that generates a simulation model, which includes a finite state machine (FSM), from the behavior level description. The simulation model generation unit generates a simulation model, in which identification information (branch ID) is assigned to a conditional branch statement in a state, and generates a behavior level description source line—branch ID correspondence table.Type: GrantFiled: September 28, 2005Date of Patent: April 21, 2009Assignee: NEC Electronics CorporationInventor: Toshimine Harada
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Publication number: 20090099828Abstract: Disclosed are embodiments of a design structure for reducing and/or eliminating mismatch. The embodiments sample the bias of one or more circuit sub-components that require a balanced state (e.g., sampling the bias of the cross-coupled transistors in each memory cell and/or sense amp in a memory array) before chip burn-in, by initiating a burn-in process during which an individually selected state is applied to each of the devices in the circuit. This fatigues the devices away from their preferred states and towards a balanced state. The bias is periodically reassessed during the burn-in process to avoid over-correction. By using this method both memory cell and sense-amplifier mismatch can be reduced in memory arrays, resulting in smaller timing uncertainty and therefore faster memories.Type: ApplicationFiled: October 12, 2007Publication date: April 16, 2009Inventors: Igor Arsovski, Harold Pilo, Michael A. Ziegerhofer
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Publication number: 20090099831Abstract: A method for generating and evaluating a table model for circuit simulation in N dimensions employing mathematical expressions for modeling a device. The table model uses an unstructured N-dimensional grid for approximating the expressions.Type: ApplicationFiled: December 4, 2008Publication date: April 16, 2009Applicant: Texas Instruments IncorporatedInventor: Gang Peter Fang
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Publication number: 20090099829Abstract: A method for operating an integrated circuit tester information processing system includes: measuring current information from test structures for an integrated circuit having a stress liner; forming a transfer curve by simulating based on the current information with a first range of first mobility multipliers; forming an inverse transfer curve by applying an inverse transfer function to the transfer curve; forming a stress curve with second mobility multipliers from the inverse curve; and validating the second mobility multipliers by comparing a measured curve and a simulated curve with the measured curve based on the current information and the simulated curve based on stress curve.Type: ApplicationFiled: October 15, 2007Publication date: April 16, 2009Applicant: ADVANCED MICRO DEVICES, INC.Inventors: Rasit Onur Topaloglu, Judy Xilin An
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Publication number: 20090099830Abstract: One embodiment of the present invention provides a system that non-intrusively detects counterfeit components in a target computer system. During operation, the system collects target electromagnetic interference (EMI) signals generated by the target computer system using one or more antennas positioned in close proximity to the target computer system. The system then generates a target EMI fingerprint for the target computer system from the target EMI signals. Next, the system compares the target EMI fingerprint against a reference EMI fingerprint to determine whether the target computer system contains a counterfeit component.Type: ApplicationFiled: October 16, 2007Publication date: April 16, 2009Applicant: Sun Microsystems, Inc.Inventors: Kenny C. Gross, Ramakrishna C. Dhanekula, Andrew J. Lewis
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Patent number: 7519526Abstract: A solution for analyzing a circuit using initial charge information is provided. In particular, one or more nodes in a design for the circuit is initialized with an initial charge. The charge can comprise a non-equilibrium charge, thereby simulating the history effect, the impact of a charged particle, electro-static discharge (ESD), and/or the like. Operation of the circuit is then simulated over the set of input cycles based on the initial charge(s). To this extent, the non-equilibrium initial condition solution enables the state of the circuit to be controlled and solves the initial system based on these values. This capability is very useful to condition the circuit at a worst-case, best-case, and/or the like, status. Further, in one embodiment of the invention, a set of equations are provided to implement the non-equilibrium initial charge analysis, which provide a more efficient initialization of the circuit than current solutions.Type: GrantFiled: February 16, 2006Date of Patent: April 14, 2009Assignee: International Business Machines CorporationInventors: Emrah Acar, Bhavna Agrawal, Peter Feldmann, Ying Liu, Steven G. Walker
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Patent number: 7519930Abstract: A circuit simulator for a semiconductor device with reduced channel length includes a method of calculating a model formula for circuit simulation of a semiconductor device; calculating first parasitic resistance independent of gate voltage using actually measured device data; calculating second parasitic resistance dependent on the gate voltage using I-V characteristic of the device without the first parasitic resistance; dividing the second parasitic resistance into channel resistance and third parasitic resistance generated under both ends of a gate length using plural kinds of diffusion resistance TEG in which the width W of each kind of diffusion resistance is the same as each other, but the length L of each kind of diffusion resistance is different from the other kinds of diffusion resistance; and obtaining an I-V characteristic formula for the semiconductor device using the third parasitic resistance as an independent characteristic.Type: GrantFiled: August 30, 2006Date of Patent: April 14, 2009Assignees: Giga Hertz Technology Corp., System Mori Ltd.Inventor: Kenji Mori
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Patent number: 7519525Abstract: Disclosed is simulation of circuit behavior by running a central electronic core simulation in a high level simulator up to and including initial microload, creation of a post-IML (initial microcode load) state, and transferring the post-initial microcode state from the central electronic core simulation to the post-initial microcode load co-simulator.Type: GrantFiled: May 11, 2004Date of Patent: April 14, 2009Assignee: International Business Machines CorporationInventor: Edward C. McCain
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Patent number: 7519523Abstract: A computer-implemented method may include defining an input bus signal in a graphical block diagram model by associating the input bus signal with a first group of signals, at least two of the first group of signals having a different data type; defining an output bus signal in the graphical block diagram model by associating the second bus signal with a second group of signals, each of the second group of signals corresponding to one of the first group of signals; defining an input to a non-virtual operation block in the graphical block diagram model as the input bus signal; defining an output to the non-virtual operation block in the graphical block diagram as the output bus signal; and simulating an operation performed on the input bus signal by the non-virtual operation block, the operation being performed on each of the first group of signals and output to each of the second group of signals.Type: GrantFiled: August 20, 2007Date of Patent: April 14, 2009Assignee: The MathWorks, Inc.Inventors: Peter Szpak, Matthew Englehart
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Patent number: 7519524Abstract: In a hardware definition language (HDL) file among one or more files, one or more design entities containing a functional portion of a digital system are specified. The one or more design entities logically contain a plurality of latches having a respective plurality of different possible latch values that each corresponds to a different configuration of the functional portion of the digital system. With one or more statements in the one or more files, a multi-level Dial tree is defined that includes a selective control Dial (SCDial) entity at an upper level that is associated with at least one design entity. The SCDial entity has a Dial input, a plurality of Dial outputs coupled to inputs of the plurality of lower level Dials, and a mapping table indicating a mapping between each of a plurality of possible input values of the Dial input and a respective one of a plurality of sets of output values for the plurality of Dial outputs.Type: GrantFiled: June 19, 2008Date of Patent: April 14, 2009Assignee: International Business Machines CorporationInventors: Bradley S. Nelson, Wolfgang Roesner, Derek Edward Williams
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Publication number: 20090094013Abstract: The present invention is a method and system for simulating the aging process of a circuit. A two-step process is employed whereby, in a first simulation step, a simulation is conducted to obtain node voltages for the original circuit and the node voltages are stored in a file. In the second step, a subsequent simulation is run after transistors of the circuit are replaced by aging subcircuits, which contain aging models, and initial node voltages are updated. A script is used to set the bias voltage inputs for the aging models using the node voltages stored in the file from the first step. With more accurate bias voltage inputs for the aging models, the aging simulations are conducted to compute the circuit degradation.Type: ApplicationFiled: October 9, 2007Publication date: April 9, 2009Applicant: Advanced Micro Devices, Inc.Inventors: Rasit O. TOPALOGLU, Jung-Suk Goo
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Patent number: 7516430Abstract: A method, apparatus, system, and signal-bearing medium that, in an embodiment, receive elements and a goal for each of the elements. In various embodiments, the elements may represent commands or parameter values for a device to be tested. Testcases are generated based on the elements. If the numbers of testcases for the elements are equally distant from their goals, then a new testcase is generated based on an element chosen at random. But, if the numbers of testcases are not equally distant from their goals, then the new testcase is generated based on the element whose number of testcases if furthest from its respective goal. The number of testcases associated with the chosen element is then incremented, and the process is repeated. In this way, the generated testcases are based on the numbers of previously generated testcases, which, in an embodiment, results in more complete coverage of testcases for the device under test.Type: GrantFiled: December 23, 2004Date of Patent: April 7, 2009Assignee: International Business Machines CorporationInventor: Sundeep Chadha
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Patent number: 7516425Abstract: A method for generating an input vector to reduce the leakage current in an integrated circuit by using heuristics includes transforming the integrated circuit to a logic representation with PMOS and NMOS parts and P and N devices of the integrated circuit into edges, selecting between PMOS and NMOS logic representations the one with deepest serial stack; and for the selected PMOS or NMOS logic representation, assigning weights to the edges, thereby generating a weighted graph. The assignment includes starting from the output terminal to the Power Vdd (for PMOS) or Ground Vss (for NMOS), and labeling edge weights in a descending order. The resulted cost function from the method of the present invention can be applied as heuristics in different algorithms, such as branch-and-bound, simulated annealing, or genetic algorithm.Type: GrantFiled: December 22, 2005Date of Patent: April 7, 2009Assignee: Industrial Technology Research InstituteInventors: Peisheng Alan Su, Li-Chuan Weng
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Patent number: 7516060Abstract: A method and apparatus for creating a memory model for use in modeling a physical memory of an electronic circuit design. Memory write operations to the physical memory and memory read operations are modeled in a lookup table. The number of entries in the lookup table is limited by an upper bound representing a total number of memory operations that can occur over a given number of clock cycles.Type: GrantFiled: September 13, 2005Date of Patent: April 7, 2009Assignee: Averant, Inc.Inventor: Adrian J. Isles
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Patent number: 7516058Abstract: IP characterization and for path finding methods, and a computer readable recording medium for storing program are provided. First, an Intellectual Property (IP) component is provided. Then, a plurality of test patterns for all paths in the IP component is automatically generated. The test patterns are then sequentially input into the IP component for simulation, and a plurality of corresponding simulation results is generated. Finally, an IP characteristic library is generated based on the simulation results.Type: GrantFiled: September 21, 2004Date of Patent: April 7, 2009Assignee: Faraday Technology Corp.Inventors: Peter Hanping Chen, Chih-Fu Chien, Jyh-Herng Wang, Hsu-Hui Tsai
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Patent number: 7516059Abstract: A logical simulation device executes simulation, based on cycle, using level sort and compile methods. In order to realize the high speed of the entire system in a practically usable scale, the system comprises a lot of processors, each capable of performing an evaluation process of executing simulation using a logical block corresponding to one or more gates as an evaluation unit, and a communication process with the other processors. A plurality of processors constitute a processor group, and a plurality of processor groups are connected to each other to form a tree-shaped hierarchy.Type: GrantFiled: June 27, 2005Date of Patent: April 7, 2009Assignee: Fujitsu LimitedInventors: Hiroaki Komatsu, Hirofumi Hamamura
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Patent number: 7516383Abstract: An extracting unit extracts unprocessed capturing destination in a circuit. A tracing unit traces an output branch point from a capturing destination and a determining unit determines an estimated failure site and a non-failure site in the circuit. A detecting unit narrows down an estimated failure site using a fail address. It is determined whether an identifying unit has identified a failure site. If the failure site has not been identified, a delay failure simulation is performed and a comparing unit compares the comparison result of the tester measurement and the result in the delay failure simulation to determine consistency between the results. The identifying unit identifies the failure site based on the consistency.Type: GrantFiled: January 30, 2006Date of Patent: April 7, 2009Assignee: Fujitsu Microelectronics LimitedInventor: Mitsuhiro Hirano
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Publication number: 20090089037Abstract: A circuit simulation method includes: generating graphical data indicating dimensions of a subject MOS transistor; calculating a parameter correction amount based on said graphical data; correcting a given transistor model parameter in response to said parameter correction amount; and performing circuit simulation of a circuit that includes said subject MOS transistor by using said corrected transistor model parameter. The parameter correction amount is calculated based on said graphical data by using arithmetic equations. The arithmetic equations include at least one stress model equation expressing a stress exerted on a channel region of a model MOS transistor. The stress model equation is suitably defined to simulate the stress exerted on the channel region.Type: ApplicationFiled: September 30, 2008Publication date: April 2, 2009Inventor: Kenta Yamada
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Patent number: 7512912Abstract: The following techniques for word-level networks are presented: constraints solving, case-based learning and bit-slice solving. Generation of a word-level network to model a constraints problem is presented. The networks utilized have assigned, to each node, a range of permissible values. Constraints are solved using an implication process that explores the deductive consequences of the assigned range values. The implication process may include the following techniques: forward or backward implication and case-based learning. Case-based learning includes recursive or global learning. As part of a constraint-solving process, a random variable is limited to a single value. The limitation may be performed by iterative relaxation. An implication process is then performed. If a conflict results, the value causing the conflict is removed from the random variable by range splitting, and backtracking is performed by assigning another value to the random variable.Type: GrantFiled: August 16, 2003Date of Patent: March 31, 2009Assignee: Synopsys, Inc.Inventor: Mahesh Anantharaman Iyer
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Patent number: 7512525Abstract: A model reduction method utilizing the rational Arnoldi method with adaptive orders (RAMAO) is applied to high-speed VLSI interconnect models. The method is based on an extension of the classical multi-point Pade approximation, using the rational Arnoldi iteration approach. Given a set of predetermined expansion points, an exact expression for the error between the output moment of the original system and that of the reduced-order system, related to each expansion point, is derived first. In each iteration of the proposed RAMAO algorithm, the expansion frequency corresponding to the maximum output moment error will be chosen. Hence, the corresponding reduced-order model yields the greatest improvement in output moments among all reduced-order models of the same order.Type: GrantFiled: January 5, 2005Date of Patent: March 31, 2009Assignee: Chang Gung UniversityInventors: Herng-Jer Lee, Chia-Chi Chu, Wu-Shiung Feng, Chao-Kai Chang
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Publication number: 20090083682Abstract: A simulation apparatus, including a first simulator assigning an operating cycle number, a second simulator assigning an operating cycle number, and a control portion for synchronously controlling the first simulator and the second simulator, the control portion causing communication between the first simulator and the second simulator so as to control control-information and synchronous-information of the first simulator and the second simulator, the control-information controlling operations of the first simulator and the second simulator, wherein the control portion sets up the operating cycle numbers of the first simulator and the second simulator at a first cycle value when a synchronous condition of the synchronous-information is established, the control portion sets up at least one of the operating cycle numbers of the first simulator and the second simulator at a second cycle value being larger than the first cycle value when the synchronous condition of the synchronous-information is not established.Type: ApplicationFiled: September 6, 2007Publication date: March 26, 2009Applicant: Kabushiki Kaisha ToshibaInventors: Takashi Akiba, Takashi Miura
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Patent number: 7509243Abstract: Two-sided projection-based model reductions have become a necessity for efficient interconnect modeling and simulations in VLSI design. In order to choose the order of the reduced system that can really reflect the essential dynamics of the original interconnect, the element of reduced model of the transfer function can be considered as a stopping criteria to terminate the non-symmetric Lanczos iteration process. Furthermore, the approximate transfer function can also be expressed as the original interconnect model with some additive perturbations. The perturbation matrix only involves at most a rank-2 modification at the previous step of the non-symmetric algorithm. The information of stopping criteria will provide a guideline for the order selection scheme used in the Lanczos model-order reduction algorithm.Type: GrantFiled: June 8, 2005Date of Patent: March 24, 2009Assignee: Chang Gung UniversityInventors: Chia-Chi Chu, Ming-Hong Lai, Wu-Shiung Feng
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Patent number: 7509608Abstract: A method for estimating jitter of an integrated circuit design is described. A description of logic blocks of the integrated circuit design is obtained. A description of input/output blocks of the integrated circuit design is obtained. A first type of a first jitter induced by operation of a logic block onto one or more first clock signals external to the logic block is determined. A second type of a second jitter induced by operation of an input/output block on one or more second clock signals external to the input/output block is determined.Type: GrantFiled: January 30, 2006Date of Patent: March 24, 2009Assignee: Xilinx, Inc.Inventor: Anthony T. Duong
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Patent number: 7509247Abstract: A modeling method is provided that includes receiving a computational model of a structure and slicing the computational model into a plurality of circuit prints. The plurality of slices may include essential circuit prints and backfill circuit prints. Various unknowns may be eliminated between essential circuit prints of the computational model. The unknowns to be eliminated may include volume unknowns and backfill circuit-print unknowns. The numerical system formed by circuit-print unknowns may be divided into a plurality of blocks. The blocks may be solved in turn. One block may be solved by projecting the contributions from other blocks to this block. The solution of the one block may be translated to other blocks to solve unknowns therein. The computational model may then be solved to determine electromagnetic and circuit characteristics of the structure.Type: GrantFiled: April 5, 2005Date of Patent: March 24, 2009Assignee: Intel CorporationInventors: Dan Jiao, Changhong Dai
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Patent number: 7509647Abstract: In hardware, performing computations on a stream typically requires handshaking signals to provide flow control. Many different handshaking protocols are available, and they are typically implemented in an ad hoc manner suited to the current design. An approach according to the invention uses a subset of the possible flow-control protocols in an effort to achieve a maximum amount of flexibility and reusability, while requiring only a moderate level of overhead when compared to manually-designed systems.Type: GrantFiled: May 23, 2002Date of Patent: March 24, 2009Assignee: Annapolis Micro Systems, Inc.Inventors: Robert L. Donaldson, Rhett D. Hudson, Lawrence M. Marshall, Jr., Michael N. Gray, James J. Sullivan, James B. Peterson, Teresa G. Smith, Michael P. Klewin, Dennis M. Hawver
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Patent number: 7509596Abstract: A power distribution network simulation method capable of speedily and accurately analyzing a large power distribution network. In the power distribution network simulation method, the large original circuit is reduced to a suitable size by using a variable reduction method, a solution of an equation of the reduced circuit is obtained, and a solution of an equation of the original circuit is restored based on the solution of the equation of the reduced circuit by using the variable reduction method. According to the power distribution network simulation method using the variable reduction method, it is possible to speedily and accurately analyze the large power distribution network.Type: GrantFiled: February 11, 2005Date of Patent: March 24, 2009Assignee: Samsung Electronics Co, Ltd.Inventors: Jong-Eun Koo, Kyung-Ho Lee, Young-Hoe Cheon
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Publication number: 20090077439Abstract: A method (200) for locating a fault in an integrated circuit (100) having a plurality of digital outputs coupled to compaction logic (140) in a test mode of the integrated circuit, the compaction logic comprising at least one output for providing a test response is disclosed. The method comprises the steps of: providing a simulation model of the integrated circuit (210); providing the simulation model with a plurality of test patterns (220); receiving a plurality of simulated test responses to said test patterns (230); defining a plurality of bits in the plurality of responses, said bits defining a signature of the fault (240); providing the integrated circuit with a further plurality of test patterns (250); receiving a plurality of test responses to said further plurality of test patterns (260); and checking the plurality of responses for the presence of the signature (270). This method provides improved fault detectability for an IC subjected thereto.Type: ApplicationFiled: October 23, 2006Publication date: March 19, 2009Applicant: NXP B.V.Inventor: Hendrikus Petrus Elisabeth Vranken
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Patent number: 7506286Abstract: Techniques and systems for debugging an electronic system having instrumentation circuitry included therein are disclosed. The techniques and systems facilitate analysis, diagnosis and debugging fabricated hardware designs at a Hardware Description Language (HDL) level. Although the hardware designs (which were designed in HDL) have been fabricated in integrated circuit products with limited input/output pins, the invention enables the hardware designs within the integrated circuit products to be comprehensively analyzed, diagnosed, and debugged at the HDL level at speed. The ability to debug hardware designs at the HDL level facilitates correction or adjustment of the HDL description of the hardware designs.Type: GrantFiled: May 2, 2006Date of Patent: March 17, 2009Assignee: Synopsys, Inc.Inventors: John Mark Beardslee, Nils Endric Schubert, Douglas L. Perry
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Patent number: 7506284Abstract: A method for simulating an integrated circuit includes performing a power supply voltage tuning operation to find a power supply voltage at which a simulation of the integrated circuit at an operating frequency passes a functional requirement, identifying a weak signal node based on the simulation result, and performing a size tuning operation on the weak signal node of the integrated circuit.Type: GrantFiled: January 19, 2006Date of Patent: March 17, 2009Assignee: Samsung Electronics Co., Ltd.Inventors: Seuk-Whan Lee, Moon-Hyun Yoo, Joon-Ho Choi
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Patent number: 7506294Abstract: A system and method for modeling an IC (integrated circuit) employs a mesh model and a grid model for separating impedance effects between nearby and far-away pairs of mesh elements. Models for relating currents and voltages can be incrementally adapted from other designs or design elements in applications including mixed-signal, analog and RF (radio frequency) circuits.Type: GrantFiled: November 17, 2006Date of Patent: March 17, 2009Assignee: Cadence Design Systems, Inc.Inventors: Enis Aykut Dengi, Feng Ling, Ben Song, Warren Harris
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Patent number: 7506297Abstract: An automatically reconfigurable high performance FPGA system that includes a hybrid FPGA network and an automated scheduling, partitioning and mapping software tool adapted to configure the hybrid FPGA network in order to implement a functional task. The hybrid FPGA network includes a plurality of field programmable gate arrays, at least one processor, and at least one memory. The automated software tool adapted to carry out the steps of scheduling portions of a functional task in a time sequence, partitioning a plurality of elements of the hybrid FPGA network by allocating or assigning network resources to the scheduled portions of the functional task, mapping the partitioned elements into a physical hardware design for implementing the functional task on the plurality of elements of the hybrid FPGA network, and iteratively repeating the scheduling, partitioning and mapping steps to reach an optimal physical hardware design.Type: GrantFiled: June 15, 2005Date of Patent: March 17, 2009Assignee: University of North Carolina at CharlotteInventors: Arindam Mukherjee, Arun Ravindran
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Patent number: 7506293Abstract: A sequential cell is characterized using interdependent setup/hold time pairs to produce associated clock-to-Q delay values, and then identifying setup/hold time pairs that produce a selected clock-to-Q delay value (e.g., 10% of failure). The identified setup/hold time pairs (or a piecewise linear (PWL) approximation thereof) are then stored in a cell library for use in static timing analysis (STA). During STA, the setup and hold skews calculated for each synchronous circuit are compared with a selected setup/hold time pair stored in the cell library (e.g., a pair having a relatively low hold value). If at least one of the setup and hold skews violates the selected setup/hold time pair, then the remaining identified setup/hold time pairs (or the PWL approximation) are utilized to determine if the synchronous circuit is violates established constraints, and if not, to identify the setup and hold times required to remove the violation.Type: GrantFiled: March 22, 2006Date of Patent: March 17, 2009Assignee: Synopsys, Inc.Inventors: Ali Dasdan, Emre Salman, Feroze P. Taraporevala, Kayhan Kucukcakar
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Patent number: 7505886Abstract: A technique for programmatically obtaining experimental measurements for model construction. A user provides criteria for the model, such as computational algorithms which characterize behavior of the real system, specifications of experiments to be performed on the real system for collecting experimental data from the real system, an identification of sought parameters which are to be derived from results of the experiments and desired tolerance constraints on the sought parameters. From experimental data collected from the real system and from the provided criteria, the inventive method and apparatus programmatically determines in an iterative loop which additional experiments are to be performed in order to achieve the desired tolerance constraints. After one or more iterations of the loop, the values for the sought parameters are determined within the desired tolerance constraints.Type: GrantFiled: September 3, 2002Date of Patent: March 17, 2009Assignee: Hewlett-Packard Development Company, L.P.Inventors: Guillermo Alvarez, Fabian E. Bustamante, Ralph Becker-Szendy, John Wilkes
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Patent number: 7505887Abstract: Methods and systems for building a simulation for verifying a design block, including efficient coordination of the control and validation of the operation of a first and second bus of the design block, with the first bus being an interface bus of a processor. An interface description is determined for a bus functional model of the interface bus of the processor. The interface description includes a synchronization bus for coordinating the bus functional model and a hardware description language (HDL) testbench. A hardware specification is generated that couples the first bus of the design block with the interface description, and couples the HDL testbench with the second bus of the design block and with the synchronization bus of the interface description. The simulation for verifying the design block is automatically generated from the bus functional model and the hardware specification.Type: GrantFiled: January 31, 2006Date of Patent: March 17, 2009Assignee: Xilinx, Inc.Inventors: John A. Canaris, Jorge Ernesto Carrillo, Lester S. Sanders, Yong Zhu
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Patent number: 7506290Abstract: A method for performing verification includes receiving a design and building for the design an intermediate binary decision diagram set containing one or more nodes representing one or more variables. A first case-splitting is performed upon a first fattest variable from among the one or more variables represented by the one or more nodes by setting the first fattest variable to a primary value, and a first cofactoring is performed upon the intermediate binary decision diagram set with respect to the one or more nodes using an inverse of the primary value to generate a first cofactored binary decision diagram set. A second cofactoring is performed upon the intermediate binary decision diagram set with respect to the one or more nodes using the primary value to generate a second cofactored binary decision diagram set, and verification of the design is performed by evaluating a property of the second cofactored binary decision diagram set.Type: GrantFiled: December 21, 2007Date of Patent: March 17, 2009Assignee: International Business Machines CorporationInventors: Christian Jacobi, Geert Janssen, Viresh Paruthi, Kai Oliver Weber
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Patent number: 7506216Abstract: A system and method for projecting reliability includes a module, such as a chip, which includes workload inputs, which account for activity on the chip. A reliability module interacts with the chip to determine a reliability measurement for the chip based upon the workload inputs such that functions of the chip are altered based upon the reliability measurement. The reliability measurements are employed to rate or improve chip designs or calculate a reliability measure in real-time.Type: GrantFiled: April 21, 2004Date of Patent: March 17, 2009Assignee: International Business Machines CorporationInventors: Pradip Bose, Jude A. Rivers, Jayanth Srinivasan
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Patent number: 7502728Abstract: Code coverage questions are addressed by a code coverage method that instruments an electronic module source design file with coverage probes and gives hierarchical names to the probes, then provides therefrom an instrumented gate level netlist. The instrumented netlist is run on a hardware emulator, executing reset trigger scripts to reset the branch and statement probes, and then a fully initialized design is driven in emulation on a simulated testbench from which the probe values are retrieved. These values can then be evaluated to determine the extent of code coverage. Various forms of coverage are supported including branch, statement, reset trigger and toggle coverage.Type: GrantFiled: December 20, 2002Date of Patent: March 10, 2009Assignee: Unisys CorporationInventors: Steven T. Hurlock, Stephen Kun, Robert A. Johnson, Jeremy S. Nichols, Arthur J. Nilson
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Patent number: 7502723Abstract: The present disclosure relates to simulating inductors wound on a ferromagnetic core as the magnetic material saturates. In one application, the present disclosure is advantageously used to model the asymmetric minor hysteresis loops commonly traversed by the output inductor of a switch mode power supply. An advantage of the subject matter of the disclosure is that it allows practical nonlinear inductors to be modeled in a computationally lightweight manner without conventional non-physical behavior under asymmetric minor hysteresis loop traversals. The disclosure is also conveniently applicable to practical ferromagnetic core materials because, in one particular implementation, the input parameters to the model are the core's coercive force (Hc), remnant magnetization flux density (Br), and saturation flux density (Bs).Type: GrantFiled: September 1, 2005Date of Patent: March 10, 2009Assignee: Linear Technology CorporationInventor: Michael Thomas Engelhardt
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Patent number: 7502724Abstract: A test simulator for simulating a test of a semiconductor device is disclosed, the test simulator including: a test pattern holding unit for holding an existing test pattern to be supplied to the semiconductor device; a device output holding unit for preliminarily holding an output to be obtained from the semiconductor device when the existing test pattern is supplied; a test pattern generating unit for generating a new test pattern to be supplied to the semiconductor device; a test pattern deciding unit for deciding whether the new test pattern is equal to the existing test pattern; and a simulation skipping unit for skipping at least a part of a simulation test by reading an output from the device output holding unit and using the output as an output for the new test pattern without supplying the new test pattern to the semiconductor device when the test patterns are equal to each other.Type: GrantFiled: September 30, 2005Date of Patent: March 10, 2009Assignee: Advantest CorporationInventors: Hideki Tada, Mitsuo Hori, Takahiro Kataoka
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Publication number: 20090063120Abstract: The present invention relates to a system for performing a co-simulation and/or emulation of hardware and software. The system includes a hardware simulator with an integrated hardware model, a hardware and/or software environment for controlling the hardware simulator and performing a software simulation and/or a direct software application, at least one synchronization facility within the hardware model for indicating a request from the hardware and/or software environment, a receiver for setting the synchronization facility into a predetermined state, and a controller for switching the hardware simulator between a free-running state and a request-handling state.Type: ApplicationFiled: August 14, 2008Publication date: March 5, 2009Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventors: Joern Babinsky, Holger Horbach, Steffen Knoll, Andreas Kohler
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Publication number: 20090055152Abstract: A system is provided for modeling an integrated circuit including at least one insulated-gate field-effect transistor. The system includes generator means for defining a parameter representing mechanical stresses applied to the active area of the transistor, and processing means for determining at least one of the electrical parameters of the transistor based at least partially on the stress parameter. Also provided is a method of modeling an integrated circuit including at least one insulated-gate field-effect transistor, and a method of producing an integrated circuit including at least one insulated-gate field-effect transistor.Type: ApplicationFiled: November 4, 2008Publication date: February 26, 2009Applicant: STMicroelectronics S.A.Inventor: RAUL ANDRES BIANCHI
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Patent number: 7496871Abstract: Various methods for analyzing mutual inductance in an integrated circuit layout are disclosed. In one exemplary embodiment, for instance, a circuit description indicative of the layout of signal wires and ground wires in the circuit is received. The signal wires and the ground wires are grouped into at least a first bundle and a second bundle, wherein the first bundle and the second bundle each comprise a respective signal-wire segment and one or more corresponding ground-wire segments. A representative dipole moment is calculated for the first bundle. Using the representative dipole moment, the mutual inductance between the first bundle and the second bundle is calculated. Computer-readable media storing computer-executable instructions for causing a computer to perform any of the disclosed methods or storing design databases created or modified using any of the disclosed techniques are also disclosed.Type: GrantFiled: October 21, 2004Date of Patent: February 24, 2009Inventors: Roberto Suaya, Rafael Escovar, Salvador Ortiz
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Patent number: 7496490Abstract: Core model processing of a processor model PE1 and a processor model PE2 is serialized. Therefore, processing time for the inter-core-model communication is required between the core model processing of a first processor model and the core model processing of a second processor model. The inter-core-model communication processing is performed such that the inter-core-model communication required for the simulation processing of a multi-processor model is performed in parallel with the core model processing.Type: GrantFiled: February 28, 2006Date of Patent: February 24, 2009Assignee: Fujitsu Microelectronics LimitedInventors: Masato Tatsuoka, Atsushi Ike
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Patent number: 7493606Abstract: A method for multi-platform parallel or real-time machine programming is provided. The method comprises specifying a parallel machine definition code defining a plurality of signal or data processing components and a communication of data or signals between the components, automatically converting the code into computer instructions for execution on an essentially sequential, non-parallel computer processor, a parallel execution of the instructions on the sequential processor and automatically converting the code into hardware programming data for providing parallel hardware operation according to the code, by including, in the hardware programming data, event control circuitry specification, priority control circuitry specification and buffering control circuitry specification to ensure that the hardware operation matches the execution on the sequential computer processor.Type: GrantFiled: August 3, 2004Date of Patent: February 17, 2009Assignee: Université du Québec à Chicoutimi (UQAC)Inventor: Luc Morin
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Patent number: 7493544Abstract: State spaces are traversed to produce test cases, or test coverage. Test coverage is a test suite of sequences. Accepting states are defined. Expected costs are assigned to the test graph states. Strategies are created providing transitions to states with lower expected costs. Linear programs and other approximations are discussed for providing expected costs. Strategies are more likely to provide access to an accepting state, based on expected costs. Strategies are used to append transitions to test segments such that the new test segment ends in an accepting state.Type: GrantFiled: January 21, 2005Date of Patent: February 17, 2009Assignee: Microsoft CorporationInventors: Andreas Blass, Colin L. Campbell, Lev Borisovich Nachmanson, Margus Veanes, Michael Barnett, Nikolai Tillmann, Wolfgang Grieskamp, Wolfram Schulte, Yuri Gurevich
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Patent number: 7493247Abstract: A method and system for verifying an integrated circuit using a Model Checker at post-silicon time to improve post-silicon assertion-based verification. A dialog is established between the Model Checker and a fabricated integrated circuit under test (ICUT), to increase the state space which is explored. ICUT-based traces from the integrated current are generated, in part based on initial states and assertions provided by the Model Checker or by a user. The Model Checker verifies the integrated circuit by generating Model Checker-based traces from basic logic, which are reproductions of the ICUT-based traces.Type: GrantFiled: December 7, 2005Date of Patent: February 17, 2009Assignee: DAFCA, Inc.Inventor: Gerard Memmi
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Patent number: 7493240Abstract: Described is a process for performing an improved mixed frequency-time algorithm to simulate responses of a circuit that receives a periodic sample signal and at least one information signal. The process selects a set of evenly spaced distinct time points and a set of reference time points. Each of the reference points is associated with a distinct time point, and a reference time point is a signal period away from its respective distinct time point. The process finds a first set of relationships between the values at the distinct time points and the values at the reference time points. The process also finds a second set of relationships between the values at the distinct time points and the values at the reference time points. The process then combines the first and second sets of relationships to establish a system of nonlinear equations in terms of the values at the distinct time points only. By solving the system of nonlinear equations, the process finds simulated responses of the circuit in time domain.Type: GrantFiled: May 15, 2000Date of Patent: February 17, 2009Assignee: Cadence Design Systems, Inc.Inventors: Dan Feng, Joel R. Phillips, Kenneth Kundert