Stats

  • Locked Locked
  • Replies 3
  • Subscribers 92
  • Views 14508
  • 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

Encounter Power Routing Flow

deeps

 Hi, 

 I am trying to create a Encounter based power routing flow, i need some suggestions as to the order of the commands that we can use, for example do we create the stripe first or the follow rails.

  I am creating the power routes in the below order

1> Create core Ring

2> Connect the core ring to the power pads 

3> Create ring for selected macros

4> Create Stripes (both Vertical & horizontl) for the core area

5> Create follow rails

       With this order when the follow are created some of the follow will be left open with-out connecting to stripes or the core ring (due to mincut via violations)

        But if i create the follow rails first & then the stripes it creates a lot of Mincut via violations.

   Would be help-full for me if some one suggest the way the power routes to be created with out creating any DRC violations.

 

thanks

deepak.

  • surajece01

    we follow similar kind of flow except that we put follow pins first and then stripes.

    1) core ring

    2) pads to core ring connection

    3)  block ring

    4) Delete all obstructs, put follow pins

    5) Stripes

    we havent faced any problem with this flow.You are getting Mincut via violations, that may not be because of paticular flow. It could be because of improper spacing between stripes. Please refer tech lef file for proper spacing if that is the problem. 

     

     

     

     

  • deeps

     Hi Suraj,

               Thanks for the replay,

                  I am trying to create a power routing flow using encounter capabilities,  so it would be helpful for me if you can share some details about the commands that you are using in your flow,

           Also please let me know about,

    • Quality of the power structure created, will they have many DRC violations
    • How do you handle or make sure the connectivity between the macro pins & the power stripes
    • How do you handle the creation of stripes in the narrow channels
    • How do you make sure that all the stripes area connected, because if there is any spacing violations are some rule violating then that stripe will be left open, how do you connect such un-connected stripes do you use "sroute" commans to connect all these unconnected stripes    

                

    thanks

    deepak.

  • surajece01
    • If you check verify geometry at each stage of adding stripes, That would reduce the overall DRC we will get at the end.
    • DRC we will have end will be min spacing and wire overlaps.
    • Connectivity between macro pins
    •               we should check the macro pins orientation (horizontal or vertical) give proper via options.         
    •               ex: macro pins in MET4 vertical ( in this case via from MET5 to MET4)
    •                there is possibilty that macro pins in MET4 horizontal ( in this case via from MET6 to MET4) use editpowervia command.
    •               Verify connectivity will show the macros for which vias are not formed.
    • In the Narrow channels we do manually add stripes (after doing verify connectivity check and stripes which are like floating.
    • Generally stripes  wont get connected to ring near io wire. you need to jog it and connect this manually. 
    • For all connectivity check use verify connectivity check with proper options. 

     

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.