Cadence Design Systems, Inc.

Kenneth S Kundert

Jacob K White

Joel Reuben Phillips

Ricardo Telichevesky

Dan Feng

Donald John O'Riordan

Henry C Chang

Walter J Ghijsen

Ted Vucurevich

Daniel Fitzpatrick

Sherry Solden

A method and mechanism for implementing a general purpose scripting language that supports parallel execution is described. In one approach, parallel execution is provided in a seamless and high-level approach rather than requiring or expecting a user to have low-level programming expertise with parallel processing languages/functions. Also described is a system and method for performing circuit simulation. The present approach provides methods and systems that create reusable and independent measurements for use with circuit simulators. Also disclosed are parallelizable measurements having looping constructs that can be run without interference between parallel iterations. Reusability is enhanced by having parameterized measurements. Revisions and history of the operating parameters of circuit designs subject to simulation are tracked.

Method and system for implementing parallel execution in a computing system and in a circuit simulator

A system and method for performing circuit simulation is described. The present approach provides methods and systems that create reusable and independent measurements for use with circuit simulators. Also disclosed are parallelizable measurements having looping constructs that can be run without interference between parallel iterations. Reusability is enhanced by having parameterized measurements. Revisions and history of the operating parameters of circuit designs subject to simulation are tracked. Mechanisms are provided that allow for viewing, measurement or other manipulation of signals at specific locations in a circuit design for simulation, such as parameters that include observation points which are implemented using probes. One approach to executing a measurement is via a controllable and flexible control statement, which in one embodiment is the 'run' statement. Improved interfaces for viewing, controlling, and manipulating simulations and simulation results are also provided.

Method and system for implementing circuit simulators

Systems and methods for storing waveform data and outputting data to a waveform viewer are disclosed. A waveform is segmented into a plurality of segments, and data describing each segment is stored at several levels of resolution. When a user wishes to view a portion of the waveform, the appropriate segments of the waveform are identified, and the appropriate levels of resolution are selected. The data describing the appropriate segments at the appropriate levels of resolution are output to a waveform viewer. An index may be provided to aid in selection of the appropriate data. Various methods for compression of the data are also supported.

Method and system for implementing a waveform viewer

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 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. The process then converts the simulated circuit responses from time domain to frequency domain.

Method and apparatus for simulating quasi-periodic circuit operating conditions using a mixed frequency/time algorithm

A system and method for performing circuit simulation is described. Revisions and history of the operating parameters of circuit designs subject to simulation are tracked. Mechanisms are provided that allow for viewing, measurement or other manipulation of signals at specific locations in a circuit design for simulation, such as parameters that include observation points which are implemented using probes. One approach to executing a measurement is via a controllable and flexible control statement, which in one embodiment is the 'run' statement. Improved interfaces for viewing, controlling, and manipulating simulations and simulation results are also provided.

Method and system for implementing, controlling, and interfacing with circuit simulators

A method is provided for compiling a model for use in a simulation, the method comprising receiving a description of the model; and automatically converting the description into an implementation of the model that is customized for a selected analysis during simulation.

Methods of model compilation for models used in an electronic circuit simulator

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. The process then converts the simulated circuit responses from time domain to frequency domain.

An efficient method for determining the periodic steady state response of a circuit driven by a periodic signal, the method including the steps of 1) using a shooting method to form a non-linear system of equations for initial conditions of the circuit that directly result in the periodic steady state response; 2) solving the non-linear system via a Newton iterative method, where each iteration of the Newton method involves solution of a respective linear system of equations; and 3) for each iteration of the Newton method, solving the respective linear system of equations associated with the iteration of the Newton method via an iterative technique. The iterative technique may be a matrix-implicit application of a Krylov subspace technique, resulting in a computational cost that grows approximately in a linear fashion with the number of nodes in the circuit.

Method for determining the steady state behavior of a circuit using an iterative technique

A system and method for generating inline subcircuits that enable a circuit designer to model and simulate circuits that when compared to conventional system and methods reduces the hierarchy from the perspective of the circuit designer, more efficiently models parasitic components, more efficiently parameterizes device models, more effectively creates models that are compatible with other simulation tools, can change the interface of a component without requiring the designer to use an extra layer of hierarchy, provides a more efficient interface by hiding details from the designer, enables hidden monitors and other functional designs to be automatically simulated by hiding these functions from the designer in a design level that is below the design level that is of interest to the designer, such as the geometrical parameter design level, can perform general purpose model binning with automatic selection, can export models and model parameters to other hierarchies without requiring an additional hierarchy in the model name, can allow sharing of exported parameterized models by devices or components that are not within the inline subcircuit definition and can modify or create outputs for models by redefining or hiding existing outputs or creating new outputs.

System and method for simulating circuits using inline subcircuits

Method for determining the steady state behavior of a circuit using an

A method and apparatus simulates the performance of a system from a user-specified description of the components in the system and the interconnections between the components. The user may specify the descriptions using a consistent syntax. Conservation relations are automatically generated using the description of the components, the interconnections between the components in the system, or both. The description provided by the user and the conservation requirements generated may be translated into models for use by a conventional simulator to complete the simulation. Alternately the description and the conservation relation may be formulated into a set of relations and solved using conventional methods, such as Modified Nodal or Sparce Tableau. System performance simulation information is then generated as desired by a user.

Growing community of inventors

Los Altos, CA, United States of America

Kenneth S Kundert