Why zero hold time is prefered?

Status
Not open for further replies.
Y

yuhiub90

Member level 2
Joined
Aug 2, 2012
Messages
52
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,288
Location
Hanoi, Vietnam, Vietnam
Visit site
Activity points
1,618
I've read an article said that today's libraries tend toward rising-edge active clocks, zero hold times, and positive set-up times. So why zero hold time is prefered to positive hold time?
Thank you.
 

Well it is always a trade-off between the logic you add to increase the hold time margin. So the minimum is zero hold time, but if with adding "few" std cells, you could increased the hold time margin, then, you are in safe side.

The hold time distribution will show you how much path are close to "zero" and then how many std cell is needed to increase your margin.
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…