FW82801E Intel, FW82801E Datasheet - Page 50

• Manufacturer Part Number: FW82801E
• Description: Communications I/O Controller Hub
• Manufacturer: Intel

Intel
3.3.2.2
3.3.3
50
Table 28. Test Mode Selection
Figure 7. Required External RTC Circuit
®
82801E C-ICH
Test Straps
External RTC Circuitry
To reduce RTC well power consumption, the 82801E C-ICH implements an internal oscillator
circuit that is sensitive to step voltage changes in VccRTC and VBIAS. Figure 7 shows a schematic
diagram of the circuitry required to condition these voltages to ensure correct operation of the
82801E C-ICH RTC.
Number of PCI Clocks RTCRST# driven low after PWROK active
•
•
•
•
VCCSUS
Note: Capacitor C2 and C3 values are crystal-dependent.
The 82801E C-ICH’s TP[0] (Test Point) signal must be pulled to Vcc3_3 with an external
pull-up resistor.
The 82801E C-ICH’s TP[1] must be routed to a test point with an option to jumper to Vcc1_8.
This test point is used for NAND tree testing. Otherwise jumper to Vcc1_8.
The 82801E C-ICH’s TP[2] must be routed to a test point with an option to jumper to V
This test point is used for NAND tree testing. Otherwise jumper to V
The 82801E C-ICH’s TP[3] must be routed to a test point with an option to jumper to V
This test point is used for NAND tree testing. Otherwise jumper to V
Vbatt
3.3V
9–24
>24
1 k
1 k
8
0.047 uF
C1
32768 Hz
Xtal
1 F
12.5 pF
C2
12.5 pF
Advance Information Datasheet
C3
Reserved. DO NOT ATTEMPT
No Test Mode Selected
SS
SS
Test Mode
.
.
All “Z”
R1
10 M
R2
10 M
VCCRTC
RTCX2
RTCX1
VBIAS
VSSRTC
SS
SS
.
.