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  3. Defining power supply symbols

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Defining power supply symbols

markbeck
markbeck over 14 years ago

I'm trying to do something which is common in BiPolar analog design, but not as much in CMOS design.  I'm trying to figure out how to create a symbol which will allow me to define a net's connectivity when placed upon that net. 

For example:
I have a schematic and symbol which have VCC and VEE defined as ports (Note: they are defined as ports to make power supply modeling easier).  To make the schematic more readable, I wish to place instance symbols which represent VCC and VEE inside the schematic which will connect those nets to the actual VCC and VEE power ports.

I know that it is possible, and I think that it was done in the past using netset, but I can't seem to find any information about netset which doesn't pertain to defining a global power and ground supply (something that I do NOT want).

Any ideas?
Mark

 

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  • markbeck
    markbeck over 14 years ago
     Hum... spoke a bit too soon. While this works in the schematic I'm running into an issue with netlisting. The stupid symbols are trying to be netlisted as instances.

     I set the nlAction=ignore in the CDF parameters, but they are still showing up.  I had to create a dummy spectre view just to keep the netliser happy, but they are showing up in the netlist.

    Setup:
    I have a library cell with a symbol and spectre view.
    In the CDF, I have set:
      Name        Prompt  Type    DefaultValue
      vdd            vdd        netSet vdd
      nlAction     nlAction string   ignore

    The netlist is being created, and the instances that have a vdd port on them do have vdd set in the netlist, so that part is working correctly.  Now I just need nlAction to work.

     Running IC6.1.5.504

    Any ideas?
    Mark

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  • markbeck
    markbeck over 14 years ago
     Hum... spoke a bit too soon. While this works in the schematic I'm running into an issue with netlisting. The stupid symbols are trying to be netlisted as instances.

     I set the nlAction=ignore in the CDF parameters, but they are still showing up.  I had to create a dummy spectre view just to keep the netliser happy, but they are showing up in the netlist.

    Setup:
    I have a library cell with a symbol and spectre view.
    In the CDF, I have set:
      Name        Prompt  Type    DefaultValue
      vdd            vdd        netSet vdd
      nlAction     nlAction string   ignore

    The netlist is being created, and the instances that have a vdd port on them do have vdd set in the netlist, so that part is working correctly.  Now I just need nlAction to work.

     Running IC6.1.5.504

    Any ideas?
    Mark

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