Signal Description
R
30
Intel
®
82925X/82925XE MCH Datasheet
2.8
Power and Ground
Name Voltage
Description
VCC 1.5
V
Core Power.
VTT 1.2
V
Processor System Bus Power.
VCC_EXP 1.5
V
PCI Express* and DMI Power.
VCCSM 1.8
V
System Memory Power.
DDR2: VCCSM = 1.8 V (VCCSM = 1.9 V for DDR2 533 CAS 3-3-3)
VCC2 2.5
V
2.5 V CMOS Power.
VCCA_EXPPLL 1.5
V
PCI Express PLL Analog Power.
VCCA_HPLL 1.5
V
Host PLL Analog Power.
VCCA_SMPLL 1.5
V
System Memory PLL Analog Power.
VSS 0
V
Ground.
2.9
Reset States and Pull-up/Pull-downs
This section describes the expected states of the MCH I/O buffers during and immediately after
the assertion of RSTIN#. This table only refers to the contributions on the interface from the
MCH and does
not
reflect any external influence (such as external pull-up/pull-down resistors or
external drivers).
Legend:
CMCT:
Common Mode Center Tapped. Differential signals are weakly driven to the common
mode central voltage.
DRIVE:
Strong drive (to normal value supplied by core logic if not otherwise stated)
TERM: Normal
termination devices are turned on
LV: Low
voltage
HV: High
voltage
IN:
Input buffer enabled
ISO:
Isolate input buffer so that it does not oscillate if input left floating
TRI: Tri-state
PU:
Weak internal pull-up
PD:
Weak internal pull-down
STRAP:
Strap input sampled during assertion or on the de-asserting edge of RSTIN#
Summary of Contents for 82925X
Page 78: ...Host Bridge DRAM Controller Registers D0 F0 R 78 Intel 82925X 82925XE MCH Datasheet...
Page 98: ...EPBAR Registers Egress Port Register Summary R 98 Intel 82925X 82925XE MCH Datasheet...
Page 108: ...DMIBAR Registers Direct Media Interface DMI RCRB R 108 Intel 82925X 82925XE MCH Datasheet...
Page 156: ...Host PCI Express Graphics Bridge Registers D1 F0 R 156 Intel 82925X 82925XE MCH Datasheet...
Page 172: ...System Address Map R 172 Intel 82925X 82925XE MCH Datasheet...
Page 192: ...Electrical Characteristics R 192 Intel 82925X 82925XE MCH Datasheet...
