data required time in PT report timing

[raviram80]

This is urgent.

Can you please let me know how data required time is calculated in the report_timing command that comes at the end. I understand how data_arrival time is calculated.

I see

In the data_arrival time section I see

clock CLK' (rise edge) 800.00 800.00
clock network delay (propagated) 3503.00 * 4303.00

In the data_required section I see the following


clock CLK' (rise edge) 800.00 800.00
clock network delay (propagated) 5111.00 * 5911.00

How is this clock network delay calculated and how is this different from clock network delay in the data arrival time section


I also see clock reconvergence pessimism and clock uncertainity as well.

Please reply at the earliest.

Regards,

Ravi

 

[raju3295]

hi ravi,
looking at ur report,
both clocks are starting at the same time, that means this is for hold analysis, and the delay for capture clock is more so my guess is correct.
both propoaged delays will be diff, as for launch path tool will take the shortest path and for the capture path it will take the longer path, so the delays will be different,
usually opposite for setup analysis.

 

[shelby]

add the option "-path full_clock_expanded" to your "report_timing" command. You will see the full clock paths going to both launch and capture endpoints.