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AR# 1423

XC3000/XC4000: Are the internal tri-state busses(3k,4k) PULLED Up by default?


Keywords: Tristate, BUFT, BUFE, XC3000, XC4000

Urgency: Standard

Internal tri-state bus for 3k and 4k families does not have
pullups on the outputs by default.


For a schematics based design, connect a PULLUP symbol on the
outputs of the internal tri-state bus.
For a behavioral design, instantiate a PULLUP primitive.
Refer to the appropriate Interface Guide for more information.
AR# 1423
Date Created 08/31/2007
Last Updated 10/07/2008
Status Archive
Type General Article