Signal Definitions
Table 5-1.
Name
Signal Definitions (Sheet 7 of 8)
Type
I
Other
Description
TESTHI[11:0] must be connected to a V
TT
power source through a resistor for proper
processor operation. Refer to
for TESTHI grouping restrictions.
Thermal Diode Anode. THERMDA connects to processor core 0, THERMDA2 connects
to processor core 1. Refer to the appropriate platform design guidelines for
implementation details.
Thermal Diode Cathode. THERMDC connects to processor core 0. THERMDC2
connects to processor core 1. Refer to the appropriate platform design guidelines for
implementation details.
Assertion of THERMTRIP# (Thermal Trip) indicates the processor junction
temperature has reached a temperature beyond which permanent silicon damage
may occur. Measurement of the temperature is accomplished through an internal
thermal sensor. Upon assertion of THERMTRIP#, the processor will shut off its
internal clocks (thus halting program execution) in an attempt to reduce the
processor junction temperature. To protect the processor its core voltage (V
CC
) must
be removed following the assertion of THERMTRIP#. Intel is currently evaluating
whether V
TT
must also be removed.
Driving of the THERMTRIP# signals is enabled within 10 ms of the assertion of
PWRGOOD and is disabled on de-assertion of PWRGOOD. Once activated,
THERMTRIP# remains latched until PWRGOOD is de-asserted. While the de-assertion
of the PWRGOOD signal will de-assert THERMTRIP#, if the processor’s junction
temperature remains at or above the trip level, THERMTRIP# will again be asserted
within 10 ms of the assertion of PWRGOOD.
TMS (Test Mode Select) is a JTAG specification support signal used by debug tools.
See the
eXtended Debug Port: Debug Port Design Guide for UP and DP Platforms
for
further information.
TRDY# (Target Ready) is asserted by the target to indicate that it is ready to receive
a write or implicit writeback data transfer. TRDY# must connect the appropriate pins
of all FSB agents.
TRST# (Test Reset) resets the Test Access Port (TAP) logic. TRST# must be driven
low during power on Reset.
V
CCA
provides isolated power for the analog portion of the internal processor core
PLL’s. Refer to the appropriate platform design guidelines for complete
implementation details.
V
CCIOPLL
provides isolated power for digital portion of the internal processor core
PLL’s. Follow the guidelines for V
CCA
, and refer to the appropriate platform design
guidelines for complete implementation details.
VCC_DIE_SENSE and VCC_DIE_SENSE2 provide an isolated, low impedance
connection to each processor core power and ground. These signals should be
connected to the voltage regulator feedback signal, which insures the output voltage
(that is, processor voltage) remains within specification. Please see the applicable
platform design guide for implementation details.
VID[5:0] (Voltage ID) pins are used to support automatic selection of power supply
voltages (V
CC
). These are CMOS signals that are driven by the processor and must be
pulled up through a resistor. Conversely, the voltage regulator output must be
disabled prior to the voltage supply for these pins becomes invalid. The VID pins are
needed to support processor voltage specification variations. See
for
definitions of these pins. The VR must supply the voltage that is requested by these
pins, or disable itself.
VID_SELECT is an output from the processor which selects the appropriate VID table
for the Voltage Regulator. Dual-Core Intel Xeon Processor 5000 series pull this signal
to ground on the package as this signal is not connected to the processor die.
VSS_DIE_SENSE and VSS_DIE_SENSE2 provide an isolated, low impedance
connection to each processor core power and ground. These signals should be
connected to the voltage regulator feedback signal, which insures the output voltage
(that is, processor voltage) remains within specification. Please see the applicable
platform design guide for implementation details.
V
SSA
provides an isolated, internal ground for internal PLL’s. Do not connect directly
to ground. This pin is to be connected to V
CCA
and V
CCIOPLL
through a discrete filter
circuit.
1
Notes
TESTHI[11:0]
THERMDA
THERMDA2
THERMDC
THERMDC2
THERMTRIP#
Other
O
TMS
I
TRDY#
I
TRST#
V
CCA
I
I
V
CCIOPLL
I
VCC_DIE_SENSE
VCC_DIE_SENSE2
O
VID[5:0]
O
VID_SELECT
O
VSS_DIE_SENSE
VSS_DIE_SENSE2
O
V
SSA
I
Dual-Core Intel® Xeon® Processor 5000 Series Datasheet
67
INTEL [ INTEL CORPORATION ]
