Intel AT80569PJ080N - Core 2 Quad 3 GHz Processor, Design Manual

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Introduction
12 Thermal and Mechanical Design Guidelines
Term Description
Ψ
CS
Case-to-sink thermal characterization parameter. A measure of thermal
interface material performance using total package power. This is defined as:
(T
C
– T
S
) / Total Package Power.
Note: Heat source must be specified for
Ψ
measurements.
Ψ
Sa
Sink-to-ambient thermal characterization parameter. A measure of heatsink
thermal performance using total package power. This is defined as: (T
S
– T
A
) /
Total Package Power.
Note: Heat source must be specified for
Ψ
measurements.
TIM
Thermal Interface Material: The thermally conductive compound between the
heatsink and the processor case. This material fills the air gaps and voids, and
enhances the transfer of the heat from the processor case to the heatsink.
P
MAX
The maximum power dissipated by a semiconductor component.
TDP
Thermal Design Power: a power dissipation target based on worst-case
applications. Thermal solutions should be designed to dissipate the thermal
design power.
IHS
Integrated Heat Spreader: a thermally conductive lid integrated into a
processor package to improve heat transfer to a thermal solution through
heat spreading.
LGA775
Socket
The surface mount socket designed to accept the processors in the 775–Land
LGA package.
ACPI
Advanced Configuration and Power Interface.
Bypass
Bypass is the area between a passive heatsink and any object that can act to
form a duct. For this example, it can be expressed as a dimension away from
the outside dimension of the fins to the nearest surface.
Thermal
Monitor
A feature on the processor that attempts to keep the processor die
temperature within factory specifications.
TCC
Thermal Control Circuit: Thermal Monitor uses the TCC to reduce die
temperature by lowering the effective processor frequency when the die
temperature has exceeded its operating limits.
DTS
Digital Thermal Sensor: Processor die sensor temperature defined as an offset
from the onset of PROCHOT#.
FSC
Fan Speed Control: Thermal solution that includes a variable fan speed which
is driven by a PWM signal and uses the on-die thermal diode as a reference to
change the duty cycle of the PWM signal.
T
CONTROL
T
CONTROL
is the specification limit for use with the on-die thermal diode.
PWM
Pulse width modulation is a method of controlling a variable speed fan. The
enabled 4-wire fans use the PWM duty cycle % from the fan speed controller
to modulate the fan speed.
Health
Monitor
Component
Any standalone or integrated component that is capable of reading the
processor temperature and providing the PWM signal to the 4-pin fan header.
BTX
Balanced Technology Extended.
TMA
Thermal Module Assembly. The heatsink, fan and duct assembly for the BTX
thermal solution