Guide

I/O Subsystem
R
Intel
®
852GM Chipset Platform Design Guide 179
Figure 93. Diode Circuit to Connect RTC External Battery
V
CCSUS
3_3
VccRTC
1.0uF
1K
A standby power supply should be used in a mobile system to provide continuous power to the RTC
when available, which will significantly increase the RTC battery life and thereby the RTC accuracy.
10.8.5. RTC External RTCRST# Circuit
Figure 94. RTCRST# External Circuit for the ICH4-M RTC
V
CCSUS
3_3
VccRTC
1.0 µF
1 k
0.1 µF
180 k
RTCRST
#
RTCRST#
CIRCUIT
DIODE/
BATTERY
CIRCUIT