X6800 Datasheet, PDF (78/122 Pages) Intel Corporation – Core2 Extreme Processor

Land Listing and Signal Descriptions
Table 26.
Signal Description (Sheet 1 of 9)
Name
Type
Description
VRDSEL
VSS
VSSA
VSS_SENSE
VSS_MB_
REGULATION
VTT
VTT_OUT_LEFT
VTT_OUT_RIGHT
VTT_SEL
Input
Input
Input
Output
Output
Input
Output
Output
This input should be left as a no connect in order for the processor
to boot. The processor will not boot on legacy platforms where this
land is connected to V_SS.
VSS are the ground pins for the processor and should be connected
to the system ground plane.
VSSA is the isolated ground for internal PLLs.
VSS_SENSE is an isolated low impedance connection to processor
core V_SS. It can be used to sense or measure ground near the
silicon with little noise.
This land is provided as a voltage regulator feedback sense point for
V_SS. It is connected internally in the processor package to the sense
point land V27 as described in the Voltage Regulator-Down (VRD)
11.0 Processor Power Delivery Design Guidelines For Desktop
LGA775 Socket.
Miscellaneous voltage supply.
The VTT_OUT_LEFT and VTT_OUT_RIGHT signals are included to
provide a voltage supply for some signals that require termination
to V_TT on the motherboard.
The VTT_SEL signal is used to select the correct V_TT voltage level for
the processor. This land is connected internally in the package to
V_TT.
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Datasheet