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hold time is negative value?

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aifi

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what happen if hold time is negative? what happen to our slack value?:?:
 

naveenbaskar

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aifi said:
what happen if hold time is negative? what happen to our slack value?:?:
if the hold is negtive. the data is arraving very fast berfore the clock.so we have to insert the data delay buffer.
 

linuxluo

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hi,
that's mean it's a wrapper contain a register, so it's negative .
 

aifi

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hi..

is that negative symbol just to show us that it is a hold time and positive for setup time?

if i have negative value for hold time in my library, is it correct to use the following formula to calculate slack:

slack(hold time) = arrival time - requered time

*i use BUILDGATES for synthesis
 

AlexWan

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Hi,

Maybe you can change your clock skew for solving it.
 

dr.farnsworth

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Hi,
To get positive slack for hold time can we also increase input delay ??

Dr.farnsworth
 

yuenkit

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what tool are you using?
what command u perfomed to get the negative hold time?
 

darylz

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hold time requirement?
 

funster

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negative hold time occus when the datapath delay is greater than

clock path delay.

best regards



aifi said:
what happen if hold time is negative? what happen to our slack value?:?:
 

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