Method and system for analyzing cross-talk coupling noise events in block-based statistical static timing

1. A method of performing statistical timing analysis of a logic design, including effects of signal coupling, the method comprising the steps of:

performing a deterministic analysis using a processor to determine deterministic coupling information for at least one aggressor/victim net pair of the logic design exhibiting coupling, assuming worst case aggressor conditions;

performing a statistical timing analysis in which the deterministic coupling information for the at least one aggressor/victim net pair is combined with statistical values of the statistical timing analysis to determine a statistical effective capacitance of a victim of the aggressor/victim net pair;

using the statistical effective capacitance to determine timing data used in the statistical timing analysis; and

conducting an update process of the timing data and the statistical timing analysis due to the effect of the coupling capacitance on a particular net to reduce pessimism.

2. The method of claim 1 , wherein the deterministic coupling information comprises multiplier/weighting factors.

3. The method of claim 2 , wherein the statistical values comprise statistical capacitance values.

4. The method of claim 3 , wherein the statistical capacitance values are parameterized.

5. The method of claim 1 , wherein the deterministic coupling information comprise victim/aggressor window overlap information.

6. The method of claim 5 , wherein the statistical values comprise statistical victim and aggressor slews and statistical coupling information.

7. The method of claim 1 , further comprising expanding aggressor/victim overlap windows to account for optimism in the deterministic timing analysis.

8. The method of claim 1 , further comprising for each block of the logic design for a predetermined set of sources of variation, determining a sensitivity of each of the predetermined set of sources of variation to each block of the logic design.

9. The method of claim 8 , wherein the predetermined set of sources of variation comprise at least one of: process variations, environmental variations, device fatigue variations and phased-lock loop variations.

10. The method of claim 8 , wherein determining a sensitivity of each of the predetermined set of sources of variation to each block of the logic design comprises, for each of the predetermined set of sources of variation, determining a change in delay between a lowest value of a variation range and a highest value of the variation range for each block of the logic design.

11. The method of claim 1 , wherein the logic design comprises a combinational integrated circuit design.

12. The method of claim 1 , wherein the logic design comprises a sequential integrated circuit design.

13. The method of claim 1 , wherein the update process comprises:

determining whether any segments of the particular net exhibit coupling;

if the particular net exhibits coupling, determining whether slack of the particular net is less than a predetermined threshold;

if the slack is less than the predetermined threshold, examining all segments of the particular net;

calculating a new statistical effective capacitance of each victim;

using the new statistical effective capacitance to determine new timing data; and

updating the statistical timing analysis using the new timing data,

wherein the worst case aggressor conditions are representative of a factor by which an effect of coupling capacitance on a net increases or decreases due to switching on the net.

14. The method of claim 13 , wherein:

determination of the factor by which the effect of coupling capacitance on the net increases or decreases comprises:

determining a coupling capacitance adder factor using a formula of A={IP/slew(aggressor)}*min{Amax, slew(victim)/interaction period (IP)}*{voltage(aggressor)/voltage(victim)};

determining a first factor by using a formula of K=(predetermined value)+A, for a late mode; and

determining a second factor by using a formula of K=(predetermined value)−A, for an early mode;

the IP is determined using a formula IP=min(slew(victim), slew(aggressor), overlap);

the statistical effective capacitance of each victim is determined using a formula Ct=Cg+K*Cc, for both the early mode and the late mode; and

Cg is actual capacitance-to-ground for a segment and Cc is coupling capacitance for the segment.

15. A computer program product for performing statistical timing analysis of a logic design, including effects of signal coupling, comprising a tangible computer usable medium having readable program code tangibly embodied in the medium, the computer program product includes at least one component operable to:

perform a deterministic analysis to determine deterministic coupling information for each aggressor/victim net pair of the logic design exhibiting coupling, assuming worst case aggressor conditions;

perform a statistical timing analysis in which the deterministic coupling information for the each aggressor/victim net pair is combined with statistical values of the statistical timing analysis to determine a statistical effective capacitance of each victim of each aggressor/victim net pair;

use the statistical effective capacitance to determine timing data used in the statistical timing analysis;

conduct an update process of the timing data and the statistical timing analysis due to the effect of the coupling capacitance on a particular net to reduce pessimism; and

for each block of the logic design for a predetermined set of sources of variation, determine a sensitivity of each of the predetermined set of sources of variation to each block of the logic design.

16. The computer program product of claim 15 , wherein the deterministic coupling information comprises multiplier/weighting factors and the statistical values comprise statistical capacitance values.

17. The computer program product of claim 15 , wherein the deterministic coupling information comprises victim/aggressor window overlap information and the statistical values comprise statistical victim and aggressor slews and statistical coupling information.

18. A method comprising the steps of:

providing a computer infrastructure operable to:

perform a deterministic analysis using a processor to determine deterministic coupling information for each aggressor/victim net pair of the logic design exhibiting coupling, assuming worst case aggressor conditions;

perform a statistical timing analysis in which the deterministic coupling information for each aggressor/victim net pair is combined with statistical values of the statistical timing analysis to determine a statistical effective capacitance of a victim of each aggressor/victim net pair;

use the statistical effective capacitance to determine timing data used in the statistical timing analysis; and

conduct an update process of the timing data and the statistical timing analysis due to the effect of the coupling capacitance on a particular net to reduce pessimism.

19. The method of claim 18 , wherein the deterministic coupling information comprises multiplier/weighting factors and the statistical values comprise statistical capacitance values.

20. The method of claim 19 , wherein the deterministic coupling information comprises victim/aggressor window overlap information and the statistical values comprise statistical victim and aggressor slews and statistical coupling information.