What is the difference of setting up a delta of 0 , tolerance of 50.... (so 0:50)
no delta, tolerance of 100...... (so :100)
since in my case, a target appears if a delta is used.
follow up question:, how does constraint manager identifies a target net....?
Thanks in advance!!
Thanks again sir...
I wanted to clarify a couple things:
Setting the Delta:Tolerance field to 0.000mil:100.000mil means the longest net in the group could be 100mils longer than the target net and the shortest net in the group could be 100 mils shorter than the target. So across all the nets you could have a variance in length as much as 200mils before seeing a DRC. (+/-100mil)
Setting the Delta:Tolerance field to :100.000mil (blank Delta field) means that all the nets could have a variance in length as much as 100mils with no specific Target. This is sometimes harder to match the members and could cause you to overly lengthen the nets.
Hope this helps,Mike Catrambone
You might want to grab a copy of the following presentation from CDNLive in 2008:
8ICP12 : Demystifying Relative Propagation Delay Constraints
Thanks Mike and Dennis..
Finally figuring this out. Though sometimes I encounter this problem:
When I set delta:tolerance, let's say, 0:50 which also means :100 (pls correct me if i'm wrong), sometimes at 0:50 setting, constraint manager reflects red colors. I think, the problem with this is the random picking of the target.