User's Manual

Introduction
8 Thermal and Mechanical Design Guidelines
1.1 Terminology
Term Description
BGA Ball Grid Array. A package type defined by a resin-fiber substrate where a die is
mounted and bonded. The primary electrical interface is an array of solder balls
attached to the substrate opposite the die and molding compound.
FC-BGA Flip Chip Ball Grid Array. A package type defined by a plastic substrate where a
die is mounted using an underfill C4 (Controlled Collapse Chip Connection)
attach style. The primary electrical interface is an array of solder balls attached
to the substrate opposite the die. Note that the device arrives at the customer
with solder balls attached.
Intel
®
ICH7 Intel
®
I/O Controller Hub 7. The chipset component that contains the primary
PCI interface, LPC interface, USB, ATA, and/or other legacy functions.
GMCH Graphic Memory Controller Hub. The chipset component that contains the
processor and memory interface and integrated graphics device.
MCH Memory Controller Hub. The chipset component that contains the processor
and memory interface. It does not contain an integrated graphics device.
T
A
The measured ambient temperature locally to the component of interest. The
ambient temperature should be measured just upstream of airflow for a
passive heatsink or at the fan inlet for an active heatsink.
T
C
The measured case temperature of a component. For processors, T
C
is
measured at the geometric center of the integrated heat spreader (IHS). For
other component types, it is generally measured at the geometric center of the
die or case.
T
C-MAX
The maximum case/die temperature with an attached heatsink. This
temperature is measured at the geometric center of the top of the package
case/die.
T
C-MIN
The minimum case/die temperature with an attached heatsink. This
temperature is measured at the geometric center of the top of the package
case/die.
TDP Thermal Design Power. TDP is specified as the highest sustainable power level
of most or all of the real applications expected to be run on the given product,
based on extrapolations in both hardware and software technology over the life
of the component. Thermal solutions should be designed to dissipate this target
power level.
TIM Thermal Interface Material. TIM is the thermally conductive material installed
between two surfaces to improve heat transfer and reduce interface contact
resistance.
lfm Linear Feet per Minute. Unit of airflow speed.
Ψ
CA
Case-to-ambient thermal characterization parameter (Psi). This is a measure of
thermal solution performance using total package power. It is defined as (T
C
T
A
) / Total Package Power. Heat source size should always be specified for Ψ
measurements.