Advanced On Chip Variation

[aditya1579]

All,

What is Advanced On-Chip Variation ?

How does it differ from the regular OCV ?

Aditya

 

[yadavvlsi]

Please go through this white paper.

 

[vimalraj205]

hai yadavvlsi,

can you plz say me whether STA in OCV is better or best/worst mode.

thank you

 

[YuLongHuang]

can you plz say me whether STA in OCV is better or best/worst mode.

HI~! I provide some of my idea about this topic:

1.
On-chip variation is more likely to be in reality since process should be gaussian distributed instead of all best/worst.

2.
Moreover, bc/wc can't guarantee the all the condition.
For example, there are combination logic for both data path and clock path.
During the setup check, we use worst case standard cell. As the result, data path is slower as expected.
However, the clock path is also slower which cause skew and make the condition better.

p.s.
After a rough review of above attachment, one of the feature of advance OCV is that it's more likely to be realistic.
As mentioned in the article, in traditional OCV, the adjacent cell may be vary so large even though it's impractical.
It's intuitive that the neighborhood cell should be both good or both bed but not one good and one bed.
Therefore, advanced OCV try to solve this issue. Of course, there are maybe other features.