Stats

  • Locked Locked
  • Replies 2
  • Subscribers 91
  • Views 13201
  • 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

*Fence* *SRC* *MME* Buffers in Clock Tree

Nataraja G

With 10.11USR1 enconter  we are seeing new type of buffers being added at CTS

*MMExc__L1_I0 these kind of naming convention was given if a pin was declared excludedPin in clock spec file

but in 10.1 *MMExc*  buffers are being added without specfying excludedPin and this is not because of  loops in clock path ( obviosuly with ckSynthesis -breakloop we are expected to see excluded buffer at loop backs )

I have never seen Insance names with *Fence* and *SRC*   in clock path 

 What do they signify ? i have searched fetxtref and socUG for these things but havn't found anything 

 

hope i am clear ,

 

Thanks

 Nataraja

its good to be back :)

 

  •  Welcome back!

    I think SRC has to do with balancing to an output port, and Fence could be due to power domains or setCTSMode -honorFence, or maybe some other things. Do any of these make sense for your design?

     

     

  •  we have set this,

     setCTSMode -honorFence false

     still fence buffer's are added and we dont have power domains in the design

     

    Fence buffers are being added to preserve a module port , in SDC file we have generated clock definitions at these ports 

    So ckSynthesis is automatically preserving them ( though i havn't specified them in clock spec file ) ,

    while i was browing in schematic viewer i found this  common to all generated clock's 

     

    i dont think SRC is for balancing Output ports , tool uses CASACDE buffer's if that is the case 

     

    Regards 

    Nataraja

     

     

     

     

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.