All, There are a number of items within the IBIS specification that are not being used in the industry. Maintaining support for these items is a burden on both EDA companies and the ability for IBIS to advance the standard to "to allow accurate modeling of new, or other I/O buffer structures." I am submitting this Deprecation BIRD as an amendment to the "Commitment to Backward Compatibility" clause that allows items to be removed from the IBIS specification and introduces a formal deprecation process. Walter Walter Katz <mailto:wkatz@xxxxxxxxxx> wkatz@xxxxxxxxxx Phone 303.449-2308 Mobile 303.335-6156