Intel Xeon User Manual

Design Guide 199
Schematic Checklist
LAN Interface
LAN_CLK • Connect to LAN_CLK on Platform LAN
Connect Device.
2
• Refer to Section 9.7.
LAN_RXD[2:0] • Connect to LAN_RXD on Platform LAN
Connect Device.
2
• ICH3-S contains integrated
9k
Ω pull-up resistors on
interface.
• Refer to Section 9.7.
LAN_TXD[2:0],
LAN_RSTSYNC
• Connect to LAN_TXD on Platform LAN
Connect Device.
2
• Refer to Section 9.7.
Miscellaneous Signals
SPKR • Has integrated pull-down. • The integrated pull-down is
enabled only at boot/ reset for
strapping functions. At all other
times, the pull-down is disabled.
• Refer to Section 9.2.
TP[0] • TP[0] requires external pull-up resistor to
VCCSUS_3.3.
AC_SDOUT • Requires a jumper to 8.2 k
Ω ± 5% pull-up
resistor to VCCSUS_3.3. Should not be
stuffed for default operation.
• This ball has a weak internal
pull-down. To properly detect a
safe_mode condition, a strong
pull-up is required to override
this internal pull down.
EE_DOUT • Prototype Boards should include a
placeholder for a pull-down resistor on this
signal line, but do not populate the resistor.
Connect to EE_DIN of EEPROM.
• ICH3-S contains an integrated
pull-up resistor for this signal.
• Connect to EEPROM data input
signal.
• (Input from EEPROM
perspective and output from
ICH3-S perspective.)
EE_DIN • No extra circuitry required. Connect to
EE_DOUT of EEPROM.
• ICH3-S contains an integrated
pull-up resistor for this signal.
• Connect to EEPROM data input
signal.
• (Ouput from EEPROM
perspective and input from
ICH3-S perspective.)
PCI Interface
PERR#
SERR#
PLOCK#
STOP#
DEVSEL#
TRDY#
IRDY#
FRAME#
REQ#[4:0]
GPIO[0]/REQ[A]#
GPIO[1]/REQ[B]#/
REQ[5]#
• These signals require a pull-up resistor.
Recommend an 8.2 k
Ω ± 5% pull-up resistor
to VCC3.3, or a 2.7 k
Ω ± 5% pull-up resistor
to VCC5.
• See the
PCI Local Bus
Specification, Revision 2.2
for
pull-up recommendations for
VCC3_3 and VCC5.
PCIRST# • Depending on the load this signal may have
to be buffered.
• Improves Signal Integrity.
Table 13-3. Intel
®
ICH3-S Schematic Checklist (Sheet 4 of 8)
Checklist Items Recommendations Comments

Intel Xeon Specifications

General

Brand	Intel
Model	Xeon
Category	Processor
Language	English