Mentor Graphics Corporation

Mark E Hofmann

Sridhar Srinivasan

Ziyang Lu

Gregory P Hackney

Systems and methods for efficient bi-directional property-based path tracing. The method includes reading a data structure corresponding to a circuit. The method also includes iteratively performing property accounting of properties as voltages propagate across devices in the circuit. The method also includes traversing series chains of similar devices in the circuit to reduce an iteration count and arrive at a circuit stability, wherein the circuit stability is determined when propagated user-specified and computed circuit properties (e.g. shortest distance) remain unchanged between subsequent iterations of the traversing. The method also includes traversing the data structure for propagated user-specified and computed property violations. The method also includes cataloging and reporting these violations in human-readable form.

Efficient bi-directional property-based path tracing

Aspects of the disclosed technology relate to techniques of voltage propagation-based reliability verification. Voltage values are propagated across components of a circuit design through global iterations until voltage values on nets of the circuit design are not changed from one global iteration to a next global iteration or one preset condition is met. At least one of the global iterations comprises local iterations for a subcircuit of the circuit design. The local iterations suspend when voltage values on nets of the subcircuit are not changed from one local iteration to a next local iteration or one preset condition is met. The propagated voltage values are then analyzed to detect problems in the circuit design.

Acceleration of voltage propagation based on local iteration

Aspects of the disclosed technology relate to techniques of scoped simulation-based ESD verification. ESD (electrostatic discharge) protection devices and I/O (input/output) circuitry are identified in a circuit design. Static simulation is performed on the I/O circuitry to determine voltage and current information for devices on current paths in the I/O circuitry based on point-to-point resistance values. Transient simulation is then performed on one or more of the ESD protection devices in the devices based on the voltage and current information and detailed parasitic information. The point-to-point resistance values and the detailed parasitic information are extracted based on a layout design for the circuit design and cross-reference information between circuit component identifiers and layout features. Results of the transient simulation are analyzed to identify ESD protection problems.

Scoped simulation for electrostatic discharge protection verification

Aspects of the disclosed technology relate to techniques of voltage-based reliability verification. Voltage values on nets of a circuit design are determined based on a combination of propagating voltage values across components of the circuit design and simulating one or more subcircuits. The one or more subcircuits are identified based on circuit topology recognition. The determined voltage values are analyzed to detect problems in the circuit design.

Reliability verification based on combining voltage propagation with simulation

This application discloses a voltage analysis tool to perform a static power aware analysis on a circuit design without having to simulate the circuit design. The voltage analysis tool can determine a set of components in the circuit design corresponds to a design pattern representing a voltage-transition device, and set an output voltage for the set of components based, at least in part, on characteristics of the voltage-transition device. The voltage analysis tool can propagate the output voltage to other portions of the circuit design, and determine whether the portions of the circuit design receiving the output voltage have a rule violation.

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Portland, OR, United States of America

Mark E Hofmann