Sunday, October 12, 2008     Register | Login | Search | Contact Us
     
   
     
     

Many of you already received communications about the move of the Cadence user community into cadence.com. And many of you have already joined, with over 4000 registrations in the first two weeks.

The new Cadence Community enhances the ability of Cadence users to connect and collaborate. In addition to moving the community into cadence.com -- enabling single sign-on for community, Sourcelink and Cadence events -- the new site is organized around nine technology segments, giving you easy access to product information, training, forums and blogs. Some of the new features include:
  • Ability to respond to posts via e-mail
  • Technology-specific blogs
  • Latest Web 2.0 social networking capabilities
  • Public profile options
  • Private messaging
  • Friends lists
Visit the new Cadence Community today at www.cadence.com/community and join the discussions!

Registration note: Due to the scope of the enhancements and the new SSO registration system, we were not able to migrate existing cdnusers.org member accounts. So new registrations are required, but this enables a broader set of functionality we think you'll enjoy.

Forum note: Under the guidance of forum moderators, we have taken the 20+ cdnusers.org forums and consolidated them into 11 forums on the new site. Posts have been brought over so you can leverage that posting history. CDNusers forums will be set to read only starting 7/30, and cdnusers.org will be redirected to the new community on 8/4.

Best regards,
Mike and Tom

Michael A. Catrambone - Steering Committee Chairman
Distinguished Engineer
PCB/Mechanical
UTStarcom, Inc.

Tom Diederich
Cadence Community Manager
Home
Forums
Forums > Custom IC > Custom IC Physical Design

Subject: LVS error for Dummy MOS
Posting to forums is available to community members only.
Login or Register
Rate this topic:
   
Author Messages
isazul
Posts: 26
Online: User is Offline
3/12/2008 6:32 PM  
Hi everybody.

I used Dummy Mos in my layout in order to have a better Matching. But when running LVS, DIVA generate error because it consider dummy MOS  as real.  There is a layer to specify dummy poly in order to avoid error due to dummy?? or there is another way to avoid that error?

I have tha same problem with ctm dummy, even if I put ctmdmy layer

thanks for your help!!
viswanadhbabu
Posts: 16
Online: User is Offline
3/12/2008 8:53 PM  
HI ,
In fabrication "Dummy mos" layer will take as metal layer . While Doing Lvs Dummy mos layer will consider as Metal layer. if Two metals unintentionally joined with dummy mos ,then tool will treat as a short.
In order to avoid this problem run DRC (it will take care of Dummy mos rules). While filling Dummy mos kept the Space to Metal layers.
isazul
Posts: 26
Online: User is Offline
3/12/2008 10:22 PM  
Hi;
In fact LVS see dummy poly as Net. I connected the 2 sides of the "dummy poly" to VDD for a PMos and to VSS for an NMos.
To which potential do you connect your dummy Poly?

It's correct when I run a DRC, There is No error.
viswanadhbabu
Posts: 16
Online: User is Offline
3/12/2008 10:43 PM  
Dummy must be connected to ground to avoid noise.

Or else

Could you mention the lvs error displayed by tool.


kvb
adbeckett
Posts: 248
Online: User is Offline
3/13/2008 12:27 AM  
In Diva you can put rules in the LVS rules to prune devices. Look in the Diva manual for information about pruning.

Better still, put the dummy devices in the schematic too - that way you can check that they're actually present...

Andrew.
Posting to forums is available to community members only.
Login or Register
Forums > Custom IC > Custom IC Physical Design > LVS error for Dummy MOS


ActiveForums 3.6
     
Copyright 2006 Cadence Design Systems, Inc.