Processor Thermal Characterization Parameter Relationships - Intel 5400 Series Design Manuallines

Thermal/Mechanical Reference Design
The case-to-local ambient thermal characterization parameter of the processor, Ψ
comprised of Ψ
local ambient thermal characterization parameter:
Equation 2-4.Ψ = Ψ
CA
Where:
Ψ
CS
Ψ
SA
is strongly dependent on the thermal conductivity and thickness of the TIM
Ψ
CS
between the heatsink and IHS.
is a measure of the thermal characterization parameter from the bottom of the
Ψ
SA
heatsink to the local ambient air. Ψ
conductivity, and geometry. It is also strongly dependent on the air velocity through
the fins of the heatsink.
Figure 2-15
parameters.
Figure 2-15. Processor Thermal Characterization Parameter Relationships
2.4.2.1 Example
The cooling performance, Ψ
characterization parameter described above:
• Define a target case temperature T
processor datasheet.
• Define a target local ambient temperature at the processor, T
The following provides an illustration of how one might determine the appropriate
performance targets. The example power and temperature numbers used here are not
related to any Intel processor thermal specifications, and are for illustrative purposes
only.
Quad-Core Intel® Xeon® Processor 5400 Series TMDG
, the TIM thermal characterization parameter, and of Ψ
CS
+ Ψ
CS SA
= Thermal characterization parameter of the TIM (°C/W).
= Thermal characterization parameter from heatsink-to-local ambient
(°C/W).
illustrates the combination of the different thermal characterization
is then defined using the principle of thermal
CA,
is dependent on the heatsink material, thermal
SA
and corresponding TDP, given in the
CASE_MAX
, is
CA
, the sink-to-
SA
.
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