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Knug's avatar
Knug
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4 years ago

set_input_delay / set_output_delay -min query

I currently have a query wrt set_input_delay / set_output_delay -min (wrt hold) : My example below : #************************************************************** # Create Clock #***********...
Knug's avatar
Knug
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4 years ago

Hi @sstrell

>> output min = data trace (min) - clock skew (max) - Th

Is this right?

Shouldn't it have been :

output min = data trace (min) - clock skew (max) + Th

sstrell's avatar
sstrell
Icon for Super Contributor rankSuper Contributor
4 years ago

No, it's correct. You subtract the hold requirement to get the smallest amount possible (-min), even if it's negative.

And clock uncertainty constraints are used to describe the properties for a clock. They don't constrain a clock directly.