Pin Listing and Signal Descriptions
Table 4-3. Signal Description (Sheet 8 of 8)
Name
Type
Description
VCC are the power pins for the processor. The voltage supplied to these pins is
determined by the VID[5:0] pins.
VCC
Input
VCCA provides isolated power for the internal processor core PLLs. Refer to the
applicable chipset platform design guide for complete implementation details.
VCCA
Input
Input
VCCIOPLL provides isolated power for internal processor FSB PLLs. Follow the
guidelines for VCCA, and refer to the applicable chipset platform design guide
for complete implementation details.
VCCIOPLL
VCC_SENSE is an isolated low impedance connection to processor core power
VCC_SENSE
VCCVID
Output (V ). It can be used to sense or measure voltage near the silicon with little
CC
noise.
1.2 V is required to be supplied to the VCCVID pin if the platform is going to
Input
Input
support the Celeron D processor. Refer to the applicable chipset platform design
guide for more information.
1.2 V is required to be supplied to the VCCVIDLB pin if the platform is going to
support the Celeron D processor. Refer to the applicable chipset platform design
guide for more information.
VCCVIDLB
VID[5:0] (Voltage ID) pins are used to support automatic selection of power
supply voltages (V ). These are open drain signals that are driven by the
CC
Celeron D processor and must be pulled up to 3.3 V with 1 kΩ 5% resistors. The
voltage supply for these pins must be valid before the VR can supply V to the
CC
VID[5:0]
Output processor. Conversely, the VR output must be disabled until the voltage supply
for the VID pins becomes valid. The VID pins are needed to support the
processor voltage specification variations. See Table 2-2 for definitions of these
pins. The VR must supply the voltage that is requested by the pins, or disable
itself.
The processor requires this input to determine that the VCCVID and VCCVIDLB
voltages are stable and within specification.
VIDPWRGD
Input
VSS are the ground pins for the processor and should be connected to the
system ground plane.
VSS
Input
VSSA
Input
VSSA is the isolated ground for internal PLLs.
VSS_SENSE is an isolated low impedance connection to processor core V . It
can be used to sense or measure ground near the silicon with little noise.
SS
VSS_SENSE
Output
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Datasheet
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