摘要:
A system and method for adjustment of modeled timing data variation as a function of past state and/or switching history during static timing analysis. One illustrative embodiment may include inputting and asserting at least one of initial signal history bound and explicit device history bound constraints for at least one signal of a circuit design and evaluating for a segment processed during a forward propagation of block based static timing analysis whether any input signal to a current segment has a bounded history, at least one of propagated and asserted. The method may further include evaluating for the segment whether history bounds are downstream from a gating restriction, and processing a next segment until there are no further segments.
摘要:
A system and method for the adjustment of history based delay variation during static timing analysis of an integrated circuit design. The method may include obtaining information through sources of variability of history based components of delay variability, and a relationship between the sources of variability and one or more bounded device histories. Then, inputting history bounds for at least one signal of the integrated circuit design, and computing and propagating history bounds through at least one first segment of the integrated circuit design to at least one signal of the integrated circuit design. Further, the method may include evaluating from at least one of the propagated history bounds, device history bounds for at least one second segment of the integrated circuit design, and based on the evaluated device history bounds, adjusting at least one of a value of the history based delay variability and propagation of timing.
摘要:
A system and method for adjustment of modeled timing data variation as a function of past state and/or switching history during static timing analysis. One illustrative embodiment may include inputting and asserting at least one of initial signal history bound and explicit device history bound constraints for at least one signal of a circuit design and evaluating for a segment processed during a forward propagation of block based static timing analysis whether any input signal to a current segment has a bounded history, at least one of propagated and asserted. The method may further include evaluating for the segment whether history bounds are downstream from a gating restriction, and processing a next segment until there are no further segments.
摘要:
A system and method for the adjustment of history based delay variation during static timing analysis of an integrated circuit design. The method may include obtaining information through sources of variability of history based components of delay variability, and a relationship between the sources of variability and one or more bounded device histories. Then, inputting history bounds for at least one signal of the integrated circuit design, and computing and propagating history bounds through at least one first segment of the integrated circuit design to at least one signal of the integrated circuit design. Further, the method may include evaluating from at least one of the propagated history bounds, device history bounds for at least one second segment of the integrated circuit design, and based on the evaluated device history bounds, adjusting at least one of a value of the history based delay variability and propagation of timing.
摘要:
Systems and methods for accommodating correlated parameters in SSTA are provided. The method includes determining a correlation between at least two parameters. The method further includes calculating a new parameter or a new parameter set based on the correlation between the at least two parameters. The method further includes performing the SSTA such that the new parameter or the new parameter set is propagated into the SSTA. The method further includes projecting slack using the correlation between the at least two parameters and using a processor.
摘要:
A method of applying common path credit in a static timing analysis in the presence of correlations between asserted arrival times, comprising the steps of using a computer, identifying one or more pairs of asserted arrival times for which one or more correlations exist; propagating to each of the one or more pairs of asserted arrival times a timing value dependent on the one or more correlations; and performing a subsequent common path pessimism removal analysis for at least one test during which a timing value dependent on the one or more correlations between asserted arrival times is used to compute an adjusted test slack.
摘要:
A method for loading checkpoint timing in an environment where the boundary arrival times, slews, required arrival times, or loads differ from the checkpoint run. A timing checkpoint file generated for one or more hierarchical modules, during which each input is assigned a unique phase tag. The association of unique phase tags allows subsequent restart analyses to efficiently adjust the checkpoint timing in relation to the restart timing environment. In the restart run, one or more such checkpoint files is read, during which an initial propagation of arrival, required arrivals and slew times are performed, followed by a local re-update based on adjusted arrival times and the required arrival times. Finally, if multiple hierarchical modules are updated, a global recalculation of timing values is performed based on a slack change threshold in order to determine whether any new timing failures have been introduced.
摘要:
A method for loading checkpoint timing in an environment where the boundary arrival times, slews, required arrival times, or loads differ from the checkpoint run. A timing checkpoint file generated for one or more hierarchical modules, during which each input is assigned a unique phase tag. The association of unique phase tags allows subsequent restart analyses to efficiently adjust the checkpoint timing in relation to the restart timing environment. In the restart run, one or more such checkpoint files is read, during which an initial propagation of arrival, required arrivals and slew times are performed, followed by a local re-update based on adjusted arrival times and the required arrival times. Finally, if multiple hierarchical modules are updated, a global recalculation of timing values is performed based on a slack change threshold in order to determine whether any new timing failures have been introduced.
摘要:
A method of applying common path credit in a static timing analysis in the presence of correlations between asserted arrival times, comprising the steps of using a computer, identifying one or more pairs of asserted arrival times for which one or more correlations exist; propagating to each of the one or more pairs of asserted arrival times a timing value dependent on the one or more correlations; and performing a subsequent common path pessimism removal analysis for at least one test during which a timing value dependent on the one or more correlations between asserted arrival times is used to compute an adjusted test slack.
摘要:
A method, system and program product are disclosed for improving an IC design that prioritize failure coefficients of slacks that lead to correction according to their probability of failure. With an identified set of independent parameters, a sensitivity analysis is performed on each parameter by noting the difference in timing, typically on endpoint slacks, when the parameter is varied. This step is repeated for every independent parameter. A failure coefficient is then calculated from the reference slack and the sensitivity of slack for each of the timing endpoints and a determination is made as to whether at least one timing endpoint fails a threshold test. Failing timing endpoints are then prioritized for modification according to their failure coefficients. The total number of runs required is one run that is used as a reference run, plus one additional run for each parameter.