Intel Celeron D, Руководство по тепловому проектированию

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30
Intel
®
Celeron
®
D Processor in the 775-Land LGA Package Thermal Design Guide
Order #303730
Intel Enabled Thermal Solutions
5.0 Intel Enabled Thermal Solutions
5.1 Thermal Solution Requirements
The thermal performance required for the heatsink is determined by calculating the
case-to-ambient thermal characterization parameter,
Ψ
CA
, as explained in Section 3.0, “Thermal
Metrology” on page 18 . This is a basic thermal engineering parameter that may be used to evaluate
and compare different thermal solutions in similar boundary conditions. For the Celeron D, an
example of how
Ψ
CA
is calculated is shown in Equation 6 .
Equation 6. Case-to-Ambient Thermal Characterization Parameter
In this calculation, T
C max
and TDP are taken from the thermal profile specification in the processor
datasheet .
Note: In this calculation, the T
C max
and TDP are constant, while
Ψ
CA
will vary according to the local
ambient temperature (T
LA
).
Table 4 shows an example of required thermal characterization parameters for the thermal solution
at various T
LA
s. This table uses the T
C max
and TDP from the processor datasheet. These numbers
are subject to change, and in case of conflict, the specifications in the processor datasheet
supersede the T
C max
and TDP specifications in this document.
Figure 8 further illustrates the required thermal characterization parameter for the Celeron D
Processor in the 775-land LGA package at various operating ambient temperatures. The thermal
solution design must have a
Ψ
CA
less than the values shown for the given local ambient
temperature.
W
C
W
C C
W TDP
C T C T
LA C
CA
o o o o o
354 . 0
84
38 7 . 67
) (
) ( ) (
max
=
−
=
−
= Ψ
Table 4. Thermal Characterization Parameter at Various T
LA
Levels
Intel
®
Celeron
®
D Processor 341 Required
Ψ
CA
(°C/W) of Thermal Solution at T
LA
= (°C)
Frequency TDP T
C MAX
44.2 40 35 30
2.93 GHz 84 W 67.7 °C 0.280 0.330 0.389 0.449