set_clock_gating_check

• Feb 21, 2006

• #1

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lizeer

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hi,
How to decide what value shoud I put for set_clock_gating_check setup & hold time? Frequency for my design is 80Mhz

 

• Feb 21, 2006

• #2

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jjww110

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set_clock_gating_check -high

maybe decided by your gated clock cell!!

 

• Feb 23, 2006

• #3

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jackson_peng

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set_clock_gating_check is set on the AND cell, which provided gated clock output.

it garantee the clock should arrive earlier than the gating signal, and its value is decided by the input pin relation of the AND cell that you selected.

generally, it is just an additional check, if you put the LATCH and AND cell close enough, then it is just no need to set.

 

• Mar 1, 2006

• #4

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silencer3

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if u have gated clocks in the design, then it is best to use set_clock_gating_check. Otherwise u may end up in surprises while testing

 

• Mar 6, 2006

• #5

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free1983

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may be this article will help u,"How To Successfully Use Gated Clocking in an ASIC design ,Darren Jones ,SNUG Boston 2002".
enjory it.
regards

 

• Aug 2, 2007

• #6

roli

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free1983 said:

may be this article will help u,"How To Successfully Use Gated Clocking in an ASIC design ,Darren Jones ,SNUG Boston 2002".
enjory it.
regards

Click to expand...

Here it is:

 

• Aug 2, 2007

• #7

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vamsi_addagada

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clock gating using the reduecd power consumtion .
clock gating means stop working of the clock.but that FF value doesnot changed

vamsi