Datasheet

Packaging and Signal Information
Intel
®
Xeon
®
Processor C5500/C3500 Series
Datasheet, Volume 1 February 2010
426 Order Number: 323103-001
12.1.10 Power Sequencing Signals
12.1.11 No Connect and Reserved Signals
VTTD Analog Processor power for the memory controller, shared cache and I/O (1.1 V).
VTTD_SENSE Analog
VTTD_SENSE and VSS_SENSE_VTT provide an isolated, low impedance connection
to the processor VTT voltage and ground. They can be used to sense or measure
voltage near the silicon.
VTT_VID[4:2] O
VTT_VID[4:2] is used to support automatic selection of power supply voltages
(V
TT
). The VR must supply the voltage that is requested by the signal after
VTTPWRGOOD is asserted. Before VTTPWRGOOD is asserted, the VRM must supply
a safe “boot voltage”.
Table 147. Reset Signals
Signal Names
I/O
Type
Description
DDR_DRAMPWROK I DDR_DRAMPRWOK processor input: connects to PCH DRAMPWROK.
SKTOCC# O
SKTOCC# (Socket Occupied): will be pulled to ground on the processor package.
There is no connection to the processor silicon for this signal. System board
designers may use this signal to determine if the processor is present.
VCCPWRGOOD I
VCCPWRGOOD (Power Good) Processor Input: The processor requires these signals
to be a clean indication that VCC, VCCPLL, VCCA, VTT supplies are stable and within
their specifications and that BCLK is stable and has been running for a minimum
number of cycles.
'Clean' implies that the signal will remain low (capable of sinking leakage current),
without glitches, from the time that the power supplies are turned on until they
come within specification.
These signals must then transition monotonically to a high state. These signals can
be driven inactive at any time, but BCLK and power must again be stable before a
subsequent rising edge of VCCPWRGOOD. These signals should be tied together
and connected to the CPUPWRGD output signal of the PCH.
VTTPWRGOOD I
The processor requires this input signal to be a clean indication that the VTT power
supply is stable and within specifications. 'Clean' implies that the signal will remain
low (capable of sinking leakage current), without glitches, from the time that the
power supplies are turned on until they come within specification. The signal must
then transition monotonically to a high state. It is not valid for VTTPWRGOOD to be
deasserted while VCCPWRGOOD is asserted.
Table 148. No Connect Signals
Signal Names Description
NC_x This signal must be left unconnected.
RSVD_x Reserved Signals. Signal can be left unconnected or routed to a test point.
Table 146. Power Signals (Sheet 2 of 2)
Signal Names
I/O
Type
Description