Cadence Design Systems, Inc.

Walter E Hartong

Paul Christopher Foster

Prabal Kanti Bhattacharya

Jinduo Sun

T Martin O'Leary

Donald John O'Riordan

Richard John O'Donovan

Timothy Martin O'Leary

William Scott Cranston

Tina Najibi

Disclosed is an approach to implement a requirements-driven analog verification flow. Disparate islands of verification tasks are performed with individual cellviews to be set into an overarching and closed loop verification flow context for a project or a complex verification task.

Method and system for implementing a requirements driven closed loop verification cockpit for analog circuits

A system, method, and computer program product for automatically providing circuit designers with verification coverage information for analog/mixed-signal circuit designs. A graphical user interface based environment allows circuit designers to assemble a schematic representation of a lower-level circuit design from pre-defined building blocks and various types of connections. Embodiments convert the schematic representation into a behavioral model for rapid simulation. Building blocks in the behavioral circuit have coverage-related terms defined either by the designer or by default, such as input and output value ranges, internal state changes, and state timers and timing-related constraints. Embodiments simulate the behavioral circuit, and determine and tangibly output coverage-related information. Manual and automatic behavioral circuit and stimulus modification can maximize coverage for improved behavioral circuit verification. Corresponding improvements to the underlying circuit may result, along with greatly reduced and better focused design and simulation efforts.

Model based analog block coverage system

Systems and methods for simulating and verifying a design are contemplated. Various embodiments determine a set of verification rules for a design, wherein the verification rules use a PSL or SVA syntax in a SPICE netlist to describ a property of the circuit design. The state of a circuit at a simulated first time, t, can be determined. The state at the first time, t, may be analyzed to determine if a triggering event has occurred. Based on the occurrence of the triggering event, the systems and methods can verify the state at the first time, t, against the set of verification rules. Some embodiments of the systems and methods described herein can include a mixed-signal circuit including an analog portion and a digital portion, and the analog portion, the mixed-signal portion, or both, may be simulated and verified.

Methods and systems for property assertion in circuit simulation

An electronic design automation (EDA) tool to validate representations of a design is disclosed. Reference and compared representations of the design are intended to respond to stimulus in the same way, but at different levels of abstraction. The reference and compared representations are simulated, at some point, to each generate waveform signals and measured results. Simulation can be with the same tool or different tools. The same or different testbench can be used on the reference and compared representations in the simulation. A design representation validation function compares the two sets of generated waveform signals and compares the two sets of measured results to identify any violations. The measured results and/or waveform signals could be loaded from previous simulations and just validated within the validation tool. Loaded simulations could be for the reference representation with just simulation of the compared representation by the validation tool, or for both with no simulations run by the validation tool. Through an optional design representation validation interface, the violations are identified and are linked to interfaces that detail the violations in greater detail, for example, to aid in debugging why the reference and compared representations are not equivalent.

Model validation cockpit

Systems and methods for simulating and verifying an analog mixed signal design provide an analog mixed signal testbench configured to verify analog parameters of the design. The testbench can include a mechanism to fetch a value of an analog object in an analog portion of a mixed signal design. The testbench mechanism can include an argument specifying the name of the object and the analog quantity to be fetched for that object. The testbench can retrieve estimated values and can further specify timing constraints specifying absolute times or events at which values are to be measured and returned.

Methods and systems for analog object fetch in mixed-signal simulation

A method and system for template-based behavioral model creation for behavioral modeling is disclosed. A design characterization and modeling (DCM) tool has a number of templates for different circuits. A designer chooses a template and customizes the template with a number of parameters and optionally pin assignments. The DCM tool generates a behavioral model that has real wire ('Wreal') capability. The transistor level design is simulated with a testbench according to the parameters to generate Wreal calibration information. The behavioral model uses the Wreal calibration information in behavioral modeling to provide quick behavioral processing of the behavioral model with the benefit of increased accuracy provided by the Wreal calibration information, for example. Optionally, the DCM tool generates another testbench that validates the analog and behavioral models.

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Isen, Germany

Walter E Hartong