Stats

  • Locked Locked
  • Replies 1
  • Subscribers 143
  • Views 12740
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Problem with hierarchical layout design

Renee

Hi,

I tried to build a MOS pcell with this function: 

I could change the length and width, or other property of MOS by stretching its layout, not by making changes to the CDF parameters. It seems that it contains a stretch handle.

I do not know how to add this stretching function to the pcell.

I tried to build a Guard Ring pcell with this function:

If Guard Ring A and Guard Ring B are put together, their contacts are overlapped which causes DRC violations.I tried to write a script that process these overlapped contacts and eliminate those violations.

But there is a problem with processing the layout of Guard Ring:

 I build the guard ring using rodCreatePath function. The contacts are part of the path. If I try to make changes to those contacts, I have to flatten that layout which I prefer not to do.

Is there any other way to build the guard ring(maybe not of path type)? Or, is there other way to edit the cell layout without flattening(edit-in-place function won't work for pcell, I've tried)?

Thanks in advance!!

 

Lei

Parents

  •  Hi Lei,

    You will want to use the SKILL function rodAssignHandleToParameter() in order to make the Pcell parameters into stretch handles. Search for this function and also "simplemos" in the documentation for a code example.  Also, your Cadence installation contains code examples which are documented in the "Sample Parameterized Cells Installation and Reference".

    For the overlapping guard rings, if you make the contacts choppable, but not the other parts of the guard ring structure you want to keep, then when you chop through the guard ring the contacts will be removed, but the non-choppable sub-parts will remain. This is a manual process, but at least it does not require the structure to be flattened.

    I hope that this answers your questions.

    Regards,

    Lawrence.

Reply

  •  Hi Lei,

    You will want to use the SKILL function rodAssignHandleToParameter() in order to make the Pcell parameters into stretch handles. Search for this function and also "simplemos" in the documentation for a code example.  Also, your Cadence installation contains code examples which are documented in the "Sample Parameterized Cells Installation and Reference".

    For the overlapping guard rings, if you make the contacts choppable, but not the other parts of the guard ring structure you want to keep, then when you chop through the guard ring the contacts will be removed, but the non-choppable sub-parts will remain. This is a manual process, but at least it does not require the structure to be flattened.

    I hope that this answers your questions.

    Regards,

    Lawrence.

Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.