Abstract: A low power integrated circuit design verification method and tool for automatically synthesizing a set of low power assertions from statements of low power intent. The low power intent statements provide low power constraint information for an integrated circuit design. The low power assertions are automatically synthesized from the low power intent statements and may be used to monitor, check and verify power controller signals. The low power assertions may also be used to collect low power functional coverage data.
Abstract: A method of system design, and more particularly a method of designing systems that achieve a set of performance goals using a hierarchically partitioned system representation wherein performance simulations are performed at multiple levels within the hierarchy and are combined to simulate a system level result in order to reduce the aggregate time required for performance simulation.
Abstract: Disclosed are methods and systems for performing false path analysis. In one approach, the methods and systems identify a set of zero or more false paths based upon both implementation-specific design data and non-implementation-specific design data. In some approaches, disclosed are methods and systems for performing automated gate-level static timing false path analysis, identification, constraint generation, and/or verification using architectural information. Static timing paths at the gate-level can be linked to the architectural information via mapping techniques found in equivalence checking (EC). The gate level static timing paths can be analyzed in the context of the architectural information to identify false paths.
Abstract: A method and system for lithography simulation is disclosed. The method and system specify a subject region of a lithography image with a CD marker, specify a threshold intensity over the lithography image, specify a gradient to a threshold value of the threshold intensity, and calculate a sensitivity or ratio of change of an image boundary of the lithography image to lithography process variation.
Abstract: An invention is provided for determining write leveling delay for a plurality of memory devices having command signals lines connected in series to each memory device is disclosed. The invention includes determining a device delay value for each memory device. Each device delay value indicates a period of time to delay a DQS signal when accessing a related memory device. Once these delay values are determined, the delay values are examined sequentially and a prior device delay value is set to a lower value, for example zero, when a subsequent device delay value of a memory device connected subsequently along the command signal lines is greater than the prior device delay value.
Abstract: A method to produce an information structure in computer readable memory that specifies power source hierarchy information for an RTL circuit design that includes multiple function instances encoded in computer readable memory, comprising: providing associations within the memory between respective function instances of the RTL design and respective power domains so as to define respective primary power domains relative to the RTL design; specifying in the memory respective secondary power domains; and providing associations within the memory that are indicative of respective power source relationships between respective primary power domains and corresponding respective secondary power domains.
Type:
Grant
Filed:
June 29, 2007
Date of Patent:
May 31, 2011
Assignee:
Cadence Design Systems, Inc.
Inventors:
Qi Wang, Pinhong Chen, Mitchell W. Hines
Abstract: The serial interface operable, for example, to facilitate high speed differential data transfer between integrated circuits provides level shifting of an incoming data signal using a switched capacitor technique which level shifts the common mode voltage with minimal attenuation and minimal reduction of bandwidths. The serial interface also includes a DC offset correction loop of the input data receiver path. The level shifting circuit operates by sensing the incoming common mode voltage of a differential data signal with a resistor divider and sampling the difference between the measured input common mode voltage and desired input differential voltages generated by a differential DAC in the DC offset correction loop on two small capacitors.
Abstract: An improved method and system are disclosed for utilizing abstracted versions of layout portions in conjunction with parameterized cells (pcells). One significant advantage is that abstracted versions of pcells can be generated from normal pcells and stored in a pcell cache, which avoids the need to abstract layout pcells on the fly.
Type:
Grant
Filed:
February 8, 2008
Date of Patent:
May 24, 2011
Assignee:
Cadence Design Systems, Inc.
Inventors:
Arnold Ginetti, Gilles S. C. Lamant, Randy Bishop, Rajan Arora
Abstract: A method for registering constraints for EDA (Electronic Design Automation) of an IC (Integrated circuit) includes: associating a constraint with values for constraint identification that identify the constraint in an IC design; associating the constraint with values for constraint relationships that relate the constraint to at least one EDA application; saving the constraint identification values and the constraint relationship values in a constraint registry element; and providing an interface to a user for accessing values of the constraint registry element.
Type:
Grant
Filed:
October 31, 2007
Date of Patent:
May 17, 2011
Assignee:
Cadence Design Systems, Inc.
Inventors:
Regis Colwell, Gilles S. C. Lamant, Alisa Yurovsky, Timothy Rosek
Abstract: In one embodiment of the invention, a method of retiming a circuit is disclosed. The method includes computing an upper bound and a lower bound for a clock period of a clock signal to clock a circuit in response to a netlist of the circuit; selecting a potential clock period for the clock signal to clock registers of the circuit in response to the computed upper bound and the computed lower bound for the clock period; computing an upper bound and a lower bound of a retiming value for each node of the circuit to determine if a retiming of the circuit is achievable with the potential clock period; and computing the retiming value for each node of the circuit to minimize circuit area in response to the computed upper bound and the computed lower bound of the retiming value for each node.
Abstract: An invention is provided for memory management in a non-volatile memory which includes a plurality of memory blocks. The invention includes loading a block table from a memory block of the non-volatile memory into system memory, where the block table includes, inter alia, a plurality of entries mapping a physical block address of the non-volatile memory to a logical block address of the non-volatile memory. The block table is updated as data is accessed in the non-volatile memory, and the updated block table is stored into a memory block of the non-volatile memory. Generally, the block table is stored periodically and/or at system shutdown.
Abstract: An integrated circuit is provided that comprises a power switch that includes a control terminal and that is coupled between a power source node and a power sink node; first data storage circuit includes a data storage input and a data storage output, wherein the data storage output is coupled to the power switch control terminal; and a second data storage circuit includes a data storage input and a data storage output, wherein the data storage input is coupled to the power sink node.
Abstract: A programmable sequence generator for controlling a flash memory device. The programmable sequence generator includes a plurality of programmable sequence registers including control phase sequence (CPS) registers and data phase sequence (DPS) registers programmed with phase sequence values corresponding to an operation command sequence of the flash memory device; and logic circuitry in a programmable command sequencer for controlling a set of states of the programmable command sequencer using the plurality of programmable sequence registers.
Abstract: A method and system for enhancing software documentation and help systems. In one embodiment, a virtual library for a selected combination of tools is created. The virtual library is then linked to the tools in the selected combination of tools. In another embodiment, a combination of tools for designing a complex software system is selected from one or more software releases. The one or more software releases comprises a plurality of available tools. The selected combination of tools comprises less than all of the plurality of available tools. Each of the plurality of available tools is associated with one or more documents. Access to only those one or more documents associated with tools in the selected combination of tools is provided.
Abstract: Disclosed is an improved method, system, and computer program product for predicting and improving the integrity, manufacturability, reliability, and performance of an electronic circuit feature based on the stresses or strains of design features of electronic designs. Some embodiments identify the design, the concurrent model(s), design feature physical or electrical parameters or attributes, analyzes the stresses or strains to predict the integrity of the design and determines whether the design meets the design objectives or constraints. Some other embodiments make corrections to the designs or the processes based upon the determination of whether the design meets the design objectives or constraints. Some other embodiments compute the variations of the design features as a result of the stresses or strains and determine their impact on the subsequent processes.
Abstract: An invention is provided for read disturbance management in a non-volatile memory. The invention includes storing a read count data for a memory location in non-volatile memory. The read count data indicating an amount of read operations accessing the memory location since data was last written to the memory location. Then, when data is read from the memory location while the value of the read count data is less than a predetermined threshold value, the value of the read count data is incremented. However, when the value of the read count data equals the predetermined threshold value, the data is moved to a new memory location, thereby avoiding read disturbance effects.
Abstract: A method and system that converges on a global solution to a PCB routing problem using iterations of topology-based routing is described. In some embodiments, the geometric design space is abstracted into a topological graph representing the routing problem. Then, each net is allowed to find its optimal solution path independent of the solution paths for all other nets. The electrical and physical constraints of the system are initially ignored or greatly relaxed. Over each design iteration, the constraints are tightened until a complete, global, topological solution is found. Once a topological solution is found, it is converted into a geometric solution. In the event that no geometric solution exists for that topological solution, then the iteration process is resumed taking into consideration this additional information. The result is the ability to quickly autoroute highly-constrained PCB designs with minimal operator input.
Type:
Grant
Filed:
April 25, 2005
Date of Patent:
May 3, 2011
Assignee:
Cadence Design Systems, Inc.
Inventors:
Ken Wadland, Richard Allen Woodward, Jr., Randall Lawson, Walter Katz, Wiley Gillmor
Abstract: Disclosed is a method and system for performing design and verification using stepwise refinement techniques, which can also include or be referred to as “top-down” design verification. With the present stepwise refinement approach, the electronic design can be acted upon at different levels of abstraction, but with approximately the same level of resolution at each abstraction level. A strong relationship of consistency exists between the successive abstraction levels of the design. On account of this consistency, properties that are established or true at one level of the design remain true for all subsequent levels of abstraction of the design.
Abstract: Methods, software, and systems implementing software provide for accepting a user's selection of a database object defining layout being displayed. The database objects can include objects defining paths and path segments. Automatic layout tools may be used in creating at least some of the objects. The user's selection begins a recursive process of automatically selecting additional database objects based on criteria designed to create an uninterrupted spine from database objects on a single interconnect layer, of the same width, and collectively arranged such that the spine has a first end and a second end, and can be traced from the first end to the second end without backtracking.
Abstract: Method and system are disclosed for modeling dynamic behavior of a transistor. The method includes representing static behavior of a transistor using a lookup table, selecting an instance of the transistor from the lookup table for modeling dynamic behavior of the transistor, computing a previous state of the instance using a non-quasi static analytical model, computing a variation in channel charge of the instance according to a rate of change in time, computing a current state of the instance using the previous state and the variation in channel charge, computing a modified terminal voltage that includes a dynamic voltage across a parasitic resistance at the terminal of the transistor according to the current state and previous state of the instance, and storing the modified terminal voltage in a memory device for modeling dynamic behavior of the transistor at the current state.
Type:
Grant
Filed:
November 6, 2007
Date of Patent:
April 26, 2011
Assignee:
Cadence Design Systems, Inc.
Inventors:
Yutao Ma, Min-Chie Jeng, Bruce W. McGaughy, Lifeng Wu, Zhihong Liu