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How to determine whether setup and hold time constrains are satisfied in a digital block? I encountered a question on the same, and it would be really helpful to know a general way to determine the same.

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  • \$\begingroup\$ Perform Worst-Case Analysis (WCA) for both. Analyze slack in the paths, data versus clock arrival. Search and explore "ASIC Static Timing Analysis" \$\endgroup\$ – CapnJJ Nov 5 '18 at 18:24
  • \$\begingroup\$ How to find the clock period though in this case? \$\endgroup\$ – Curiosity Nov 5 '18 at 18:36
  • \$\begingroup\$ It might expect your answer to be in the form of LTE to a given frequency, and/or offset, for no violations(?) Maybe this example will help: vlsiuniverse.blogspot.com/2016/10/… you should be able to find several other examples too \$\endgroup\$ – CapnJJ Nov 5 '18 at 19:23
  • \$\begingroup\$ Okay. Thanks. Can you please just tell me one additional thing: as per this logic, the frequency of the arrangement should be the inverse of (2+11+2+9+2) ns. Is it right? \$\endgroup\$ – Curiosity Nov 5 '18 at 19:54
  • \$\begingroup\$ yep... frequency, by definition, is 1/(time). Certainly you knew this already, given what you are working on(?) Timing "bites" even the most seasoned engineers, so be slow and deliberate in your calculations and draw it out if you need, each element on a separate line so you can see the delays and decide if it makes sense. \$\endgroup\$ – CapnJJ Nov 5 '18 at 19:58
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ummm... Did you get that from a website, or do you have a (possibly lazy) professor that copied it (exactly) and gave it to you otherwise? Ha, either way, your answer is right here... check your work with it, or at least make sure you understand it:

http://www.vlsi-expert.com/2011/05/example-of-setup-and-hold-time-static.html

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