Regarding the MCMM and OCV analysis

[qual_ti]

Hi,

In lastest designs,at advanced nodes we do MCMM analysis and also do OCV analysis.

my question is "even though we are doing MCMM analysis, why we do OCV analysis "?

Can I get some basic to advance on both MCMM and OCV ? Any links based on this ?




regards
qual_ti

 

[rca]

MCMM is only multi corner & Multi mode, that's means, you indicate to the tool, all the combination (rc-library) where you want the tool check the setup and the hold time.
OCV (On Chip Variation), just add more timing varation over the design, for all the MCMM, it it generally apply after CTS, to fix the remaining hold/setup violations (or in general the smallest margin)

 

[qual_ti]

my question is even though we have more number of corners, for say more than 1000 corners, even though shall we do OCV analysis ?

 

[lostinxlation]

if you got 1000 corners and you want to do OCV, why not ?
You just pick the right corner combination if you don't want to spend whole 21st century to do the timing analysis with 1000*999/2 differnt combinations.

 

[matter]

Yes, even if you have a 1000 corners, you would still want to do OCV analysis (at advanced nodes). Likewise even if you have just 1 corner, you can do OCV analysis.

 

[jeevan.life]

my question is even though we have more number of corners, for say more than 1000 corners, even though shall we do OCV analysis ?

OCV is for variations in specific parts of the chip compared to other parts of the chip. When you create 1000 corners, these account for the entire chip not the concept of OCV. So we need OCV even if you have 10000 corners to have a stable chip.