February, 2007
Internal Pull-Up Resistors
3.3
Internal Pull-Up Resistors
The signals listed in Table 3-2 have a weak internal pull-up resistor. If a listed signal is not used and no
board trace is connected to the ball, the internal resistor is normally sufficient to keep the signal from
toggling. If a listed signal is not used, but is connected to a board trace, the internal resistors might not
be strong enough to hold the signal in the inactive state, and therefore it is recommended that the signal
be pulled High to VDD33 or Low to VSS (GND), as appropriate, through a 3K- to 10K-Ohm resistor.
Table 3-2. Balls with Internal Pull-Up Resistors
Signal Name
EE_DO
HP_PRSNT[3:0]#
HP_PRSNT[11:8]#
HP_PWRFLT[3:0]#
HP_PWRFLT[11:8]#
JTAG_TCK
JTAG_TDI
HP_BUTTON[3:0]#
HP_BUTTON[11:8]#
HP_MRL[3:0]#
JTAG_TMS
JTAG_TRST#
HP_MRL[11:8]#
ExpressLane PEX 8532AA/BA/BB/BC 8-Port/32-Lane Versatile PCI Express Switch Data Book
Copyright © 2007 by PLX Technology, Inc. All Rights Reserved – Version 1.6
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