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 Ultrasim: individual accuracy setting on subcircuit level ? 

Last post Mon, Mar 3 2014 3:55 AM by Andrew Beckett. 3 replies.
Started by baenischfau 27 Feb 2014 10:40 AM. Topic has 3 replies and 930 views
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  • Thu, Feb 27 2014 10:40 AM

    Ultrasim: individual accuracy setting on subcircuit level ? Reply

    Hi all,

     

    I'm currently simulating a big mixed signal block, consisting of two big blocks. The instance block I0 is

    pure digital logic, instance I1 is mainly analog but also includes some digital parts. I'm using Ultrasim

    for verification but due to the analog parts I'm forced to use a quite strict accuracy setting to get the

    results about right. However this setting is killing the digital part ...

     

    I know that some other simulators offer the possibility to define accuracy levels for each instance in

    a design, e.g. set I0 to Digital Fast and I1 to Analog. Is something like this possible with Ultrasim ?

     

    Best Regards

     

    Andi

    • Post Points: 20
  • Fri, Feb 28 2014 10:31 AM

    Re: Ultrasim: individual accuracy setting on subcircuit level ? Reply

    Andi,

    This can be done in the hierarchy editor. Create a config view (File->New->CellView and pick your lib cell view and set the Type to be "config". Then when this opens, hit Use Template and pick "spectre". Make sure that the top cellView is pointing to your schematic and OK that form.

    You'll then get a Table view showing Cell Bindings and a Tree View showing instance bindings - this is how you control which views are used for each cell or instance with greater control than just a view list and stop list which is applied everywhere.

    For Ultrasim usage, use View->Properties. You'll see some additional columns appear in the table and tree view, including sim_mode and speed. You can click on these for a particular cell, or a particular instance. sim_mode is a cyclic with the various sim_mod choices (e.g.  s, a, ms, da, df, dx) - and you can also set the speed.

    Save your setup, and then you can hit the Open button in the hierarchy editor to open the configured schematic, From here, launch ADE (you'll see ADE shows the config as being the view being simulated) and then if Ultrasim is the simulator, it will take this information and add it to the netlist so that Ultrasim knows the per-cell or per-instance mode and speed settings.

    Hope that helps,

    Regards,

    Andrew.

    • Post Points: 20
  • Mon, Mar 3 2014 12:30 AM

    Re: Ultrasim: individual accuracy setting on subcircuit level ? Reply

     Hi Andrew,

     

    Thank you very much. Found it and trying it right now. 

    However I'm puzzled by one simulator output. Even though I set one instance to df and one to s

    the device model statistics reports only devices set to spice. Shouldn't there also be devices listed

    that are set to df ? I'm using MMSIM 12.11.115 

     

    Best Regards

     

    Andi

     

    • Post Points: 20
  • Mon, Mar 3 2014 3:55 AM

    Re: Ultrasim: individual accuracy setting on subcircuit level ? Reply

    Andi,

    I suggest you contact customer support - I don't have time to check this out myself right now.

    Kind Regards,

    Andrew.

    • Post Points: 5
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Started by baenischfau at 27 Feb 2014 10:40 AM. Topic has 3 replies.