Intel N450 AU80610004653AA User Manual
Product codes
AU80610004653AA
Thermal Specifications and Design Considerations
70
Datasheet
6.1.4
Out of Specification Detection
Overheat detection is performed by monitoring the processor temperature and
temperature gradient. This feature is intended for graceful shut down before the
THERMTRIP# is activated. If the processor’s TM1 is triggered and the temperature
remains high, an “Out Of Spec” status and sticky bit are latched in the status MSR
register and generates thermal interrupt.
temperature gradient. This feature is intended for graceful shut down before the
THERMTRIP# is activated. If the processor’s TM1 is triggered and the temperature
remains high, an “Out Of Spec” status and sticky bit are latched in the status MSR
register and generates thermal interrupt.
6.1.5
PROCHOT# Signal Pin
An external signal, PROCHOT# (processor hot), is asserted when the processor die
temperature has reached its maximum operating temperature. If TM1 is enabled, then
the TCC will be active when PROCHOT# is asserted. The processor can be configured to
generate an interrupt upon the assertion or deassertion of PROCHOT#.
temperature has reached its maximum operating temperature. If TM1 is enabled, then
the TCC will be active when PROCHOT# is asserted. The processor can be configured to
generate an interrupt upon the assertion or deassertion of PROCHOT#.
The processor implements a bi-directional PROCHOT# capability to allow system
designs to protect various components from overheating situations. The PROCHOT#
signal is bi-directional in that it can either signal when the processor has reached its
maximum operating temperature or be driven from an external source to activate the
TCC. The ability to activate the TCC via PROCHOT# can provide a means for thermal
protection of system components.
designs to protect various components from overheating situations. The PROCHOT#
signal is bi-directional in that it can either signal when the processor has reached its
maximum operating temperature or be driven from an external source to activate the
TCC. The ability to activate the TCC via PROCHOT# can provide a means for thermal
protection of system components.
Only a single PROCHOT# pin exists at a package level of the processor. When the core's
thermal sensor trips, PROCHOT# signal will be driven by the processor package. If TM1
is enabled, PROCHOT# will be asserted and only the core that is above TCC
temperature trip point will have its core clock modulated. If TM2 is enabled and the
core is above TCC temperature trip point, it will enter the lowest programmed TM2
performance state. It is important to note that Intel recommends both TM1 and TM2 to
be enabled.
thermal sensor trips, PROCHOT# signal will be driven by the processor package. If TM1
is enabled, PROCHOT# will be asserted and only the core that is above TCC
temperature trip point will have its core clock modulated. If TM2 is enabled and the
core is above TCC temperature trip point, it will enter the lowest programmed TM2
performance state. It is important to note that Intel recommends both TM1 and TM2 to
be enabled.
When PROCHOT# is driven by an external agent and if only TM1 is enabled on the core,
then the processor core will have the clocks modulated. If TM2 is enabled, then the
processor core will enter the lowest programmed Intel Thermal Monitor-2 performance
state. It should be noted that Force TM1 on TM2, enabled via BIOS, does not have any
effect on external PROCHOT#. If PROCHOT# is driven by an external agent when TM1,
TM2, and Force TM1 on TM2 are all enabled, then the processor will still apply only
TM2.
then the processor core will have the clocks modulated. If TM2 is enabled, then the
processor core will enter the lowest programmed Intel Thermal Monitor-2 performance
state. It should be noted that Force TM1 on TM2, enabled via BIOS, does not have any
effect on external PROCHOT#. If PROCHOT# is driven by an external agent when TM1,
TM2, and Force TM1 on TM2 are all enabled, then the processor will still apply only
TM2.
PROCHOT# may be used for thermal protection of voltage regulators (VR). System
designers can create a circuit to monitor the VR temperature and activate the TCC
when the temperature limit of the VR is reached. By asserting PROCHOT# (pulled-low)
and activating the TCC, the VR will cool down as a result of reduced processor power
consumption. Bi-directional PROCHOT# can allow VR thermal designs to target
maximum sustained current instead of maximum current. Systems should still provide
proper cooling for the VR and rely on bi-directional PROCHOT# only as a backup in case
of system cooling failure. The system thermal design should allow the power delivery
circuitry to operate within its temperature specification even while the processor is
designers can create a circuit to monitor the VR temperature and activate the TCC
when the temperature limit of the VR is reached. By asserting PROCHOT# (pulled-low)
and activating the TCC, the VR will cool down as a result of reduced processor power
consumption. Bi-directional PROCHOT# can allow VR thermal designs to target
maximum sustained current instead of maximum current. Systems should still provide
proper cooling for the VR and rely on bi-directional PROCHOT# only as a backup in case
of system cooling failure. The system thermal design should allow the power delivery
circuitry to operate within its temperature specification even while the processor is