Guide

Intel
®
Celeron
®
D Processor for Embedded Applications Thermal Design Guide 7
Introduction
T
LA
(T
Local-Ambient
)
The measured ambient temperature locally surrounding the processor. The
ambient temperature shall be measured just upstream of a passive heatsink, or at
the fan inlet for an active heatsink.
Thermal Design Power
(TDP)
A design point for the processor. OEMs must design thermal solutions that meet
or exceed TDP and T-case specifications as specified by the processor’s
datasheet.
Thermal Interface Material
(TIM)
The thermally conductive compound between the heatsink and processor case.
This material fills the air gaps and voids, and enhances the spreading of the heat
from the case to the heatsink.
U
A unit of measure used to define server rack spacing height. 1U is equal to 1.75
inches, 2U equals 3.50 inches, etc.
Ψ
CA
The case-to-ambient thermal characterization parameter (psi). A measure of
thermal solution performance using total package power. Defined as (T
C
-
T
A
)/Total package power.
NOTE: Heat source must be specified for Ψ measurements.
Ψ
CS
The case-to-sink thermal characterization paameter. A measure of thermal
interface material performance using total package power. Defined as (T
C
-
T
S
)/Total package power.
NOTE: Heat source must be specified for Ψ measurements.
Ψ
SA
The sink-to-ambient thermal characterization parameter. A measure of heatsink
thermal performance using total package power. Defined as (T
S
- T
A
)/Total
package power.
NOTE: Heat source must be specified for Ψ measurements.
Table 2. Definitions of Terms
Term Definition