How to see the critical path of the design?

You should use Timequest to find this information. Specify your timing requirements and which clock frequencies you must use in your design, and any path that is too long to fit your requirements will end up in the "Top failing paths" report.

AFAIK Timequest gives a Fmax for all 3 timing models used.

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You should use Timequest to find this information. Specify your timing requirements and which clock frequencies you must use in your design, and any path that is too long to fit your requirements will end up in the "Top failing paths" report.

AFAIK Timequest gives a Fmax for all 3 timing models used.

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Thanks. I got it. Sometimes, when I read the fmax, the report posts several clocks in my

design with different fmax. What is mean of that?

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If you have several clocks in your design, each one is analysed by Timequest, and the maximum possible value is given for each one of them.

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So that means there is a critical path for each clock. I just realize that I can check the critical path if it fails to meet time requirements in "Top failing paths" report. But if my design meet time requirement, but I still want to find where the critical path is, what should I do？

Thanks very much.

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Just look at slack figures. The smallest slack is the critical path.

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Thanks very much, kaz.