Home > Community > Forums > PCB Design > How to manage die capacitance in a stacked device in IBIS model?

Email

* Required Fields

Recipients email * (separate multiple addresses with commas)

Your name *

Your email *

Message *

Contact Us

* Required Fields
First Name *

Last Name *

Email *

Company / Institution *

Comments: *

 How to manage die capacitance in a stacked device in IBIS model? 

Last post Thu, May 18 2006 1:58 AM by archive. 4 replies.
Started by archive 18 May 2006 01:58 AM. Topic has 4 replies and 784 views
Page 1 of 1 (5 items)
Sort Posts:
  • Thu, May 18 2006 1:58 AM

    • archive
    • Top 75 Contributor
    • Joined on Fri, Jul 4 2008
    • Posts 88
    • Points 4,930
    How to manage die capacitance in a stacked device in IBIS model? Reply

    Hello everybody,

    I've a stacked (4x die) IBIS model for my device. During the operation one device is active at a time. Each die has a different capacitance (c_comp) however R_pkg, L_pkg & C_pkg should be the same. 

    How will I set c_comp in the IBIS model as it is a variable parameter?

    Thanks,
    Saad.


    Originally posted in cdnusers.org by Saad
    • Post Points: 0
  • Mon, May 22 2006 12:09 PM

    • archive
    • Top 75 Contributor
    • Joined on Fri, Jul 4 2008
    • Posts 88
    • Points 4,930
    RE: How to manage die capacitance in a stacked device in IBIS model? Reply

    Using the IBIS keyword [Model Selector] might do the trick for you.


    [Pin]  signal_name   model_name   R_pin   L_pin    C_pin
    |
    A1     IO1                 StackIO          
    ...

    [Model Selector]  StackIO
    Die1_IO                  IO for first die
    Die2_IO                  IO for second die
    Die3_IO                  IO for third die
    Die4_IO                  IO for fourth die
    ...

    [Model]        Die1_IO
    Model_type     I/O
    |
    Vinl = 650.000mV
    Vinh = 1.150V
    Vmeas = 900.000mV
    Vref = 900.000mV
    Cref = 0.0pF
    Rref = 25.000Ohm
    |
    |                            typ                 min                 max
    |
    C_comp                      2.690pF             2.290pF             3.070pF
    |
    ...

    Then from Sigxp you could select which buffer to use in the simulation.



    Originally posted in cdnusers.org by aaront
    • Post Points: 0
  • Tue, May 23 2006 4:11 AM

    • archive
    • Top 75 Contributor
    • Joined on Fri, Jul 4 2008
    • Posts 88
    • Points 4,930
    RE: How to manage die capacitance in a stacked device in IBIS model? Reply

    Aaront's approach or something similar is the only way to go. In SigXP, you can chose the buffer easily. If you want to run lists of nets in probe, you have to run several batch jobs using the different model cases.


    Originally posted in cdnusers.org by Kalevi2
    • Post Points: 0
  • Tue, May 23 2006 5:19 AM

    • archive
    • Top 75 Contributor
    • Joined on Fri, Jul 4 2008
    • Posts 88
    • Points 4,930
    RE: How to manage die capacitance in a stacked device in IBIS model? Reply

    thanks Aaront, thanks Kai for your help!
    Regards Saad.


    Originally posted in cdnusers.org by Saad
    • Post Points: 0
  • Tue, Jun 13 2006 1:09 PM

    • archive
    • Top 75 Contributor
    • Joined on Fri, Jul 4 2008
    • Posts 88
    • Points 4,930
    RE: How to manage die capacitance in a stacked device in IBIS model? Reply

    Clever trick for swapping drivers, but it seems you should also 4x C_comp too?


    Originally posted in cdnusers.org by Donald Telian
    • Post Points: 0
Page 1 of 1 (5 items)
Sort Posts:
Started by archive at 18 May 2006 01:58 AM. Topic has 4 replies.