7021 - All Nexus / Radiant 2023.1 and older: How can the user calculate the Clock-To-Out (min and max) values and Input setup/hold values of the I/O Timing Analysis report?

The Clock-to-Out max value is the setup analysis' arrival time of data with the output port's external timing path.

The Clock-To-Out min value is the hold analysis' arrival time of data with the output port's external timing path.

By default, timing analysis is performed at the device speed grade for setup and at m speed grade for hold. 

To match them, the user needs to change the speed grade for hold analysis on the Timing Options.



Setup analysis and Clock-To-Out max as example:



 

Regarding the input setup and input hold times on the I/O Timing Analysis report, this is defined by Lattice as the difference between the data and clock arrival times:

Input setup value = Tsu + Tdata - Tclk
Input hold value = -Th + Tclk - Tdata

See the input setup value calculation as an example.

This is discussed in an old Timing closure document, https://www.latticesemi.com/view_document?document_id=45588, on the Lattice website, but this is particularly for Diamond. The user can see on page 4 the explanation for the input setup/hold value. At the same time, the user can refer to Figures 4 and 5 on the document.

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