Stats

  • Locked Locked
  • Replies 3
  • Subscribers 91
  • Views 14193
  • 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

Getting critical path extraction from encounter to spice

Jdevos

Hello,

I've analyzed a circuit with encounter and I've found the critical path. Now I would like to make a Monte Carlo analysis of this path with a spice simulator.

My point is therefore to know if there is a way to extract the spice netlist of my critical path? I've tried to use the ETS tool but it asked me for a cdB file in order to perform a noise calculation. However I don't have this file for the design kit I'm using. Moreover I don't feel it is really necessary to make a noise calculation in order to extract the critical path in a spice file. Therefore my question is: is there another way to get this file?

Thanks a lot for your help!

  • According to the documentation, you don't have to run a noise analysis to get the spice, but you do have to issue the "set_noise_run_mode" command before the "create_spice_deck -report_timing" command. Try providing a "dummy" cdB file and see if you can get your spice output. Let us know if it works!

  • Hi Kari

    First of all thanks a lot for your help.

    I've tried to load a dummy cdB as you suggested but it doesn't work. Actually after executing the command create_spice_deck, I got the following warning :
    "**WARN:  (SI-2252) SPICE trace cannot be simulated or output. The noise library (cdB) data needs to be loaded prior to running the set_noise_run_mode command. You can use the read_lib -cdb to load the noise library (cdB) files or specify it through a configuration file." (Although my cdB file is loaded with my .conf)

    Just below I got several warnings like this one:
    "**WARN: (SI-2000) cdB may be missing spice definition for cell HS65_LS_IVX7 (needed for port clk__L1_I0:A)                    [sim_path]"

    To be sure I'm not missing something, here is a list of the commands I execute after loading my .conf (the dummy cdb is loaded in the .conf)

    read_spef file.spef
    set_noise_run_mode -process 65nm
    set_noise_parm spice_include {nameofmy.spi}
    create_spice_deck

    (I've tried some other things but I got the same result)

     

  •  Hi,

    Did you get this working? Hopefully you filed a service request and someone was able to help you.

     

    - Kari

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.