Cri Azzolini
Community Member
![* *](https://designers-guide.org/forum/Templates/Forum/default/stargold.gif) ![* *](https://designers-guide.org/forum/Templates/Forum/default/stargold.gif)
Offline
Posts: 48
University of Parma, Italy
|
Hi all,
I am verifying a design where parasitic path on layout may be critical. The layout has been extracted with Assura RCX in modality "only-R" and then back-annotate the parasitic on the Virtuoso schematic editor with "Parasitics" menu and "report terminal-to-terminal". Selecting the desired terminals I obtain a list of poly/metal resistance contributions and the sum of them all as expected. But... I repeated the Assura extraction with "RC" mode and repeated the back annotation between the same terminals and ... the result was different: the overall parasitic R on the same net was almost 50% higher!
I am puzzled because I thought that "only-R" extracted a subset of parasitics from "RC".
Did anybody of you find such behaviour? I also tried to extract a parasitic spectre/spice netlist for visual inspection but I am not able to have the parasitics lumped (i.e. an RC pair for every net).
Any help is welcome. Thanks in advance, bye. Cristiano
|