Leaving The Gmch Dvob Or Dvoc Port Unconnected; Miscellaneous Input Signals And Voltage Reference; Gvref Reference Voltage - Intel 855GME Design Manual

®
Intel 855GME Chipset and Intel
6.5.1

Leaving the GMCH DVOB or DVOC Port Unconnected

When the motherboard does not implement any of the possible video devices with the DVO port,
follow the guidelines recommended on the motherboard. DVO Output signals may be left
unconnected if they are not used.
Pull-down resistors are required for the following signals if not used:
•
DVOBFLDSTL
•
DVOCFLDSTL
•
DVOBCCLKINT
Pull-up resistors are required for the following signals if not used:
•
DVOBCINTR#
6.6

Miscellaneous Input Signals and Voltage Reference

ADDID[7]: Pull-down to ground with a 1 K Ω resistor when using the DVOB or DVOC port.
•
This is a vBIOS strapping option to load the TPV AIM module for DVOB and DVOC port.
Pull-down not required if DVOB or DVOC is not enabled.
•
ADDID[6:0]: Leave unconnected (NC).
•
DVODETECT: Leave unconnected (NC) when using the DVOB or DOVC port.
•
DVORCOMP is used to calibrate the DVOB buffers. It shall be connected to ground via a
40.2 Ω 1 percent resistor using a routing guideline of 10 mil trace and 20 mil spacing.
•
DPMS: Connects to 1.5 V version of the Intel
S1.
•
GVREF: Reference voltage for the DVOB and DVOC input buffers. Refer to
proper signal conditioning.
Figure 82. GVREF Reference Voltage
®
6300ESB ICH Embedded Platform Design Guide
1 KΩ 1%
GVREF (to DVO device)
0.1 μF
1 KΩ 1%
January 2007
Integrated Graphics Display Port
®
6300ESB SUSCLK or a clock that runs during
+V1.5S
GVREF(to GMCH)
0.1 μF
Figure 82 for
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