Article ID: 000081965 Content Type: Product Information & Documentation Last Reviewed: 10/01/2013

How do I perform IBIS simulation when a VREF pin is used as general purpose regular I/O pin?



The pin capacitance is higher on VREF pins than general purpose I/O pins.  The IBIS models do not contain the additional pin capacitance for the VREF pins when used as regular I/O pins.  You should add an input capacitor to your IBIS simulation to account for the additional capacitance.

Refer to the respective device datasheet for the VREF pin capacitance value for the device you are targeting. 



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