AOCV

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AOCV (ADVANCE ON_CHIP_VARITIONS) 

Aocv will be calculated with the depth and distance by seeing above figure you will get an idea. for the above figure we will consider depth as 6 because path-1 is the longest path from the above fig. so tool will take the depth as 6 from the aocv file and distance is calculated with the help of will the diagonal distance.

But AOCV will be calculated from the diverging point only.

Note: just understanding purpose I kept buffer in the above diagram in place of buffers it may gates flops etc..

AOCV setting can be done on both PNR tools and STA tools.

While doing analysis we will flow some time Graph based Analysis and Path based Analysis both 

With the help of AOCV we will get 3 to 4% of pessimism 

 lets see some difference between GBA and PBA

GBA

it will have worst skew (transitions)

its not realistic 

fast analyzer

less memory required

worst aocv derating will occurs.. etc 

PBA

Actual skew will be propagated

its more realistic 

slow analyzer

more memory required

Actual aocv derating will occurs. etc


   



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