specifying constraints in synopsys on output clocks 
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 specifying constraints in synopsys on output clocks

>I think this also will work provided u need to fix the hold time for all
>possible violations ( offcourse :-) )

>    create_clock -name "CLK" -period 20 -waveform {0,10} clock_name

>     set_fix_hold CLK

Wakharkar, a lot of Synopsys users tend to skip adding any fix hold
constraints because hold violations are fairly easy to deal with (even
at the last minute in a design) compared with all the work you're going
to do to get those set-up constraints met.  In the early days, there
used to be just one clock creating command that did both the set-up
and hold constraining, but Synopsys split the command into create_clock
and set_fix_hold just so we would not be wasting our time doing hold fixes
on designs not making it set-up wise.

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Tue, 09 Feb 1999 03:00:00 GMT  
 [ 1 post ] 

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