876784 Intel, 876784 Datasheet - Page 78

• Manufacturer Part Number: 876784
• Manufacturer: Intel

Specifications of 876784

• Lead Free Status / RoHS Status: Compliant

Table 2-23. Functional Strap Definitions (Sheet 3 of 3)
2.24.2
Figure 2-4.
78
NOTE: See
External RTC Circuitry
To reduce RTC well power consumption, the ICH7 implements an internal oscillator
circuit that is sensitive to step voltage changes in VccRTC.
example schematic recommended to ensure correct operation of the ICH7 RTC.
Example External RTC Circuit
NOTE: C1 and C2 depend on crystal load.
LINKALERT#
REQ[4:1]#
and Mobile
and Mobile
SATALED#
(Desktop
(Desktop
Signal
Only)
Only)
SPKR
VccSus3_3
Vbatt
TP3
1 KΩ
Section
+
–
XOR Chain
XOR Chain
No Reboot
Reserved
Reserved
Selection
Entrance
Usage
Schottky
(20% tolerance)
3.1for full details on pull-up/pull-down resistors.
Diodes
20 KΩ
1 µF
Rising Edge of
Rising Edge of
Rising Edge of
Sampled
PWROK
PWROK
PWROK
When
32.768 kHz
Xtal
§
1 µF
(20% tolerance)
(5% tolerance)
This signal requires an external pull-up resistor.
See
This signal has a weak internal pull-up enabled only
when PLTRST# is asserted.
NOTE: This signal should not be pulled low.
The signal has a weak internal pull-down. If the
signal is sampled high, this indicates that the
system is strapped to the “No Reboot” mode (ICH7
will disable the TCO Timer system reboot feature).
The status of this strap is readable via the NO
REBOOT bit (Chipset Config Registers:Offset
3410h:bit 5).
See
signal has a weak internal pull-up.
NOTE: This signal should not be pulled low unless
15 pF
Chapter 25
Chapter 25
C1
using XOR Chain testing.
(5% tolerance)
for functionality information.
for functionality information. This
15 pF
C2
Figure 2-4
Comment
Intel
®
ICH7 Family Datasheet
10 MΩ
shows an
R1
Signal Description
VCCRTC
RTCX1
RTCX2
RTCRST#