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Seadog's avatar
Seadog
Icon for Occasional Contributor rankOccasional Contributor
7 years ago

Timing closure on Arria 10

I am trying to close timing on an Arria 10 Design (A057K2F40I2). I would like to know if some of the problems I am seeing are device limitations, or just tool issues or operator error. The first co...
Seadog's avatar
Seadog
Icon for Occasional Contributor rankOccasional Contributor
7 years ago

I am sorry, but I am unable to insert or attach image files (not sure if this is some IT problem on my end or what). Regardless, I think there is enough information in my posting to describe the problem, primarily:

  • Internal delay in an I/O cell (pad to register input) can be as high as 5 ns
  • a combinatorial circuit with ~150 inputs requires 30 levels of 6-input LUTs (not just 30 LUTs, a a timing chain 30 LUTs deep).

Thanks again.