Intel® Core™ 2 Duo Mobile
Processors on 45-nm process for
Embedded Applications
Thermal Design Guide
June 2008
Order Number: 320028-001
Core™ 2 Duo Mobile Processors—Contents
Contents
1.0 Introduction ............................................................................................................. 6
2.0 Package Information ................................................................................................ 9
3.0 Thermal Specifications.............................................................................................10
4.0 Mechanical Specifications ........................................................................................11
4.1.1 Die Pressure/Load Upper Limit..................................................................11
4.1.2 Die Pressure/Load Lower Limit..................................................................11
5.0 Thermal Solution Requirements...............................................................................15
®
6.0 Reference Thermal Solutions ...................................................................................18
Keep Out Zone Requirements..............................................................................19
Thermal Performance.........................................................................................19
1U+ Reference Heatsink.....................................................................................19
6.4.1 Keep Out Zone Requirements...................................................................20
6.4.2 Thermal Performance..............................................................................20
6.5.1 Keep Out Zone Requirements...................................................................22
6.5.2 Thermal Performance..............................................................................22
Heatsink Fastener Assembly................................................................................22
7.0 Thermal Metrology...................................................................................................24
Additional Thermal Features................................................................................24
7.4.1 Active Heatsink Measurements .................................................................25
7.4.2 Passive Heatsink Measurements................................................................25
8.0 Reliability Guidelines ...............................................................................................28
Thermal Solution Component Suppliers....................................................................29
Mechanical Drawings ...............................................................................................30
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Figures—Core™ 2 Duo Mobile Processors
Figures
Thermal Design Process..............................................................................................7
Primary Side Keep Out Zone Requirements— Micro-FCPGA ............................................ 12
Secondary Side Keep Out Zone Requirements.............................................................. 14
10 CompactPCI Reference Heatsink Assembly .................................................................. 21
11 cPCI Reference Heatsink Thermal Performance vs. Volumetric Flow Rate ......................... 22
12 Heatsink Orientation Relative to Airflow Direction ......................................................... 23
13 Measuring TLA with an Active Heatsink ....................................................................... 26
14 Measuring TLA with a Passive Heatsink ....................................................................... 27
17 AdvancedTCA* Reference Heatsink Assembly............................................................... 33
18 AdvancedTCA* Reference Heatsink............................................................................. 34
21 CompactPCI* Reference Heatsink Assembly................................................................. 37
22 CompactPCI* Reference Heatsink............................................................................... 38
23 1U Reference Heatsink PCB Keep Out Requirements (Sheet 1 of 2)................................. 39
24 1U Reference Heatsink PCB Keep Out Requirements (Sheet 2 of 2)................................. 40
25 1U Reference Heatsink Assembly ............................................................................... 41
26 1U Reference Heatsink.............................................................................................. 42
Tables
Definition of Terms.....................................................................................................7
®
Thermal Specifications for the Intel Core™2 Duo processor.......................................... 10
Required Heatsink Thermal Performance (Ψ )............................................................. 17
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Core™ 2 Duo Mobile Processors—Tables
Revision History
Date
Revision
Description
June 2008
1.0
First Public release.
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Introduction—Core™ 2 Duo Mobile Processors
1.0
Introduction
The power dissipation of electronic components has risen along with the increase in complexity of
computer systems. To ensure quality, reliability, and performance goals are met over the product’s life
cycle, the heat generated by the device must be properly dissipated. Typical methods to improve heat
dissipation include selective use of airflow ducting, and/or the use of heatsinks.
The goals of this document are to:
• Identify the thermal and mechanical specification for the device.
• Describe a reference thermal solution that meets the specifications.
A properly designed thermal solution will adequately cool the device at or below the thermal
specification. This is accomplished by providing a suitable local-ambient temperature, ensuring
adequate local airflow, and minimizing the die to local-ambient thermal resistance. Operation outside
the functional limits can degrade system performance and may cause permanent changes in the
operating characteristics of the component.
This document describes thermal design guidelines for the Intel® Core™ 2 Duo Mobile Processors on
45-nm process for Embedded Applications in the micro Flip Chip Pin Grid Array (micro-FCPGA)
package and the micro Flip Chip Ball Grid Array (micro-FCBGA) package. The information provided in
this document is for reference only and additional validation must be performed prior to implementing
the designs into final production. The intent of this document is to assist each original equipment
manufacturer (OEM) with the development of thermal solutions for their individual designs. The final
heatsink solution, including the heatsink, attachment method, and thermal interface material (TIM)
must comply with the mechanical design, environmental, and reliability requirements delineated in
the processor datasheet. It is the responsibility of each OEM to validate the thermal solution design
with their specific applications.
This document addresses thermal and mechanical design specifications for the Intel Core 2 Duo
processor only. For thermal design information on other Intel components, refer to the respective
component datasheets.
1.1
Design Flow
Several tools are available from Intel to assist with the development of a reliable, cost-effective
thermal solution. Figure 1 illustrates a typical thermal solution design process with available tools
noted. The tools are available through your local Intel field sales representative.
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Core™ 2 Duo Mobile Processors—Introduction
Figure 1.
Thermal Design Process
Step 1: Thermal Simulation
• Package Level Thermal Models
Step 2: Heatsink Design
and Selection
• Thermal Model User’s Guide
• Reference Heatsinks
• Reference Mounting Hardware
• Vendor Contacts
Step 3: Thermal Validation
• Thermal Testing Software
• Thermal Test Vehicle
• User Guides
1.2
Definition of Terms
Table 1.
Definition of Terms (Sheet 1 of 2)
Term
Definition
Flip Chip Pin Grid Array. A pin grid array packaging technology where the die is
exposed on the package substrate.
FCPGA
FCBGA
Flip Chip Ball Grid Array. A ball grid array packaging technology where the die is
exposed on the package substrate.
T
Maximum allowed component (junction) temperature. Also referred to as T
J-MAX
JUNCTION-MAX
Thermal Design Power. Thermal solutions should be designed to dissipate this
target power level.
TDP
Local ambient temperature. This is the temperature measured inside the chassis,
T
LA
approximately 1 inch upstream of a component heatsink. Also referred to as T .
A
Junction-to-ambient thermal characterization parameter. A measure of heatsink
Ψ
thermal performance using the total package power. Defined as (T
Total Package Power
– T ) /
JA
JUNCTION LA
Thermal interface material thermal characterization parameter. A measure of
thermal interface material performance using total package power. Defined as (T
Ψ
TIM
– T
)/ Total Package Power. Also referred to as Ψ
CASE
JUNCTION
JS.
Sink-to-ambient thermal characterization parameter. A measure of heatsink
Ψ
thermal performance using total package power. Defined as (T
Total Package Power.
– T
)/
SA
SINK
JUNCTION
°C
Degrees in Celsius
CFM
in.
Volumetric airflow rate in cubic feet per minute
Inches
LFM
PCB
Airflow velocity in linear feet per minute
Printed circuit board
T
Heatsink temperature measured on the underside of the heatsink base.
SINK
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Introduction—Core™ 2 Duo Mobile Processors
Table 1.
Definition of Terms (Sheet 2 of 2)
Term
Definition
Thermal Interface Material – the thermally conductive compound between the
heatsink and die. This material fills air gaps and voids, and enhances spreading of
the heat from the die to the heatsink.
TIM
A unit of measure used to define server rack spacing height. 1U is equal to 1.75
inches, 2U equals 3.50 inches, etc.
U
W
Watt
1.3
Reference Documents
The reader of this specification should also be familiar with material and concepts presented in the
following documents:
• Intel® Core™2 Duo Processor for Intel® Centrino® Duo Mobile Technology Datasheet
Documents are located at developer.intel.com. Contact your Intel field sales representative for
additional information.
1.4
Thermal Design Tool Availability
Intel provides thermal simulation models of the device and a thermal model user’s guide to aid
system designers in simulating, analyzing, and optimizing thermal solutions in an integrated, system-
level environment. The models are for use with commercially available Computational Fluid Dynamics
(CFD)-based thermal analysis tools including Flotherm* (version 7.1 or higher) by Flomerics, Inc. or
Icepak* by Fluent, Inc. Contact your Intel representative to order the thermal models and associated
user’s guides.
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Core™ 2 Duo Mobile Processors—Package Information
2.0
Package Information
The Intel® Core™2 Duo Processor (XE and SV) is available in 478-pin Micro-FCPGA packages as well
as 479-ball Micro-FCBGA packages. The Intel® Core™2 Duo Processor SFF processor (LV and ULV) is
available in 956-ball Micro-FCBGA packages. The package mechanical dimensions can be found in the
product’s datasheet.
The Micro-FCBGA package incorporates land-side capacitors. The land-side capacitors are electrically
conductive. Care should be taken to prevent the capacitors from contacting any other electrically
conductive materials. Doing so may short the capacitors and possibly damage the device or render it
inactive.
The processor package has mechanical load limits that are specified in the processor datasheet. These
load limits should not be exceeded during heatsink installation, removal, mechanical stress testing, or
standard shipping conditions. The heatsink mass can also add additional dynamic compressive load to
the package during a mechanical shock event. Amplification factors due to the impact force during
shock must be taken into account in dynamic load calculations. The total combination of dynamic and
static compressive load should not then exceed the processor datasheet compressive dynamic load
specification during a vertical shock. It is not recommended to use any portion of the processor
substrate as a mechanical reference or load bearing surface in either static or dynamic compressive
load conditions.
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Thermal Specifications—Core™ 2 Duo Mobile Processors
3.0
Thermal Specifications
3.1
Thermal Design Power
FCBGA, micro-FCPGA package and socket via the base board is negligible. The cooling capacity
without a thermal solution is also minimal, so Intel requires the use of a heatsink for all usage
conditions.
3.2
Maximum Allowed Component Temperature
thermal solution is required to meet the temperatures specification while dissipating the Thermal
Design Power.
®
Table 2.
Thermal Specifications for the Intel Core™2 Duo processor
T
T
J-MIN
(°C)
J-MAX
CPU
Processor SKU#
TDP (W)
(°C)
Standard Voltage (Core 2 Duo-6M, Celeron-2M)
Low Voltage (Core 2 Duo -3M)
35
17
10
Intel® Core™ 2 Duo
Mobile Processors
on 45-nm process
105
0
Ultra Low Voltage (Core 2 Duo -2M, Celeron)
=
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Core™ 2 Duo Mobile Processors—Mechanical Specifications
4.0
Mechanical Specifications
4.1
Package Mechanical Requirements
Die Pressure/Load Upper Limit
4.1.1
From a die mechanical integrity standpoint, the maximum allowable normal die load is the lesser of
2
2
15 lbs or 100 psi. Considering the 15 lbs load limit and the nominal die area of 1.45 cm (0.22 in. ),
this equates to a die pressure of 66.7 psi (below 100 psi specification). Considering the maximum
pressure specification, the die load at this pressure would be 22.4 lbs, exceeding the 15 lbs. load
limit. Thus, the heatsink clamping mechanism (spring loaded fasteners, spring clips, etc.) should not
exceed 15 lbs.
4.1.2
Die Pressure/Load Lower Limit
From a TIM performance standpoint, a minimum die pressure is required to ensure consistent and
minimal TIM thermal resistance. This lower value is a function of the TIM used. For the phase-change
TIM specified for thermal solutions mentioned later, die pressure should not be lower than
approximately 138 kPa (20 psi). This will keep TIM resistance better than approximately
o
2
0.30 C-cm /W.
4.2
Package Keep Out Zones Requirements
should include a means to prevent the heatsink from forming an electrical short with the capacitors
placed on the top side of the package. The reference thermal solutions include z-stops machined into
the base of the heatsink. The z-stops prevent the heatsink from inadvertently tilting when installed.
Other methods are suitable including using electrically insulated gasket material at the base of the
heatsink.
4.3
Board Level Keep Out Zone Requirements
A general description of the keep-out zones and mounting hole pattern for the reference thermal
Components placed between the underside of the heatsink and motherboard cannot exceed 4.75 mm
micro-FCPGA package.
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Core™ 2 Duo Mobile Processors—Thermal Solution Requirements
5.0
Thermal Solution Requirements
5.1
Thermal Solution Characterization
The thermal characterization parameter, Ψ (“psi”), is used to characterize thermal solution
performance, as well as compare thermal solutions in identical situations (i.e., heating source, local
ambient conditions, etc.). It is defined by the following equation:
Equation 1. Junction-to-Local Ambient Thermal Characterization Parameter (Ψ )
JA
TJ −TA
ΨJA =
TDP
Ψ
= Junction-to-local ambient thermal characterization parameter (°C/W)
JA
T
= Maximum allowed device temperature (°C)
JUNCTION MAX
A
measurement guidelines)
TDP = Thermal Design Power (W)
The thermal characterization parameter assumes that all package power dissipation is through the
thermal solution (heatsink), and is equal to TDP. A small percentage of the die power (< 5%) is
dissipated through the package/socket/motherboard stack to the environment, and should not be
considered to be a means of thermal control.
The junction-to-local ambient thermal characterization parameter, Ψ , is comprised of Ψ , which
JA
JS
includes the thermal interface material thermal characterization parameter, and of Ψ , the sink-to-
SA
local ambient thermal characterization parameter:
Equation 2. Junction-to-Local Ambient Thermal Characterization Parameter
ΨJA = ΨJS + ΨSA
Where:
Ψ
= Thermal characterization parameter from junction-to-sink, this also includes thermal resistance
JS
of the thermal interface material (Ψ ) (°C/W).
TIM
Ψ
= Thermal characterization parameter from sink-to-local ambient (°C/W)
SA
Ψ
is a measure of the thermal characterization parameter from the bottom of the heatsink to the
SA
local ambient air. Ψ is dependent on the heatsink material, thermal conductivity, and geometry. It is
SA
also strongly dependent on the air velocity through the fins of the heatsink. Figure 5 illustrates the
combination of the different thermal characterization parameters.
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Thermal Solution Requirements—Core™ 2 Duo Mobile Processors
Figure 5.
Processor Thermal Characterization Parameter Relationships
TA
ΨSA
HEATSINK
Ψ
JA
TIM
TS
TJ
Ψ
TIM
Device
5.1.1
Calculating the Required Thermal Performance for the Intel®
Core™2 Duo processor
Overall thermal performance, Ψ
is then defined using the thermal characterization parameter:
JA,
• Define a target component temperature T
and corresponding TDP.
JUNCTION
• Define a target local ambient temperature, T .
A
The following provides an illustration of how to determine the appropriate performance targets.
Assume:
• TDP = 35 W and T
= 105 °C
JUNCTION
• Local processor ambient temperature, T = 40 °C.
A
Using Equation 1, the maximum allowable resistance, junction-to-ambient, is calculated as:
Equation 3. Maximum Allowable Resistance
TJ −TA
TDP
105−40
ΨJA =
=
=1.857 o C /W
35
To determine the required heatsink performance, a heatsink solution provider would need to
determine Ψ performance for the selected TIM and mechanical load configuration. If the heatsink
CA
solution were designed to work with a TIM material performing at Ψ
≤ 0.50 °C/W, solving from
TIM
Equation 2, the performance of the heatsink required is:
Equation 4. Required Performance of the Heatsink
o
ΨSA = ΨJA − ΨJS =1.86− 0.50 =1.36 C /W
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Core™ 2 Duo Mobile Processors—Thermal Solution Requirements
It is evident from the above calculations that a reduction in the local ambient temperature can have a
significant effect on the junction-to-ambient thermal resistance requirement. This effect can
contribute to a more reasonable thermal solution including reduced cost, heatsink size, heatsink
weight, or a lower system airflow rate.
Processors on 45-nm process. Since the data is based on air data at sea level, a correction factor
would be required to estimate the thermal performance at other altitudes.
Table 3.
Required Heatsink Thermal Performance (Ψ )
JA
TDP
(W)
Ψ
(ºC/W)
Ψ
(ºC/W)
JA
A
JA
A
CPU
Processor SKU
at T = 40 ºC
at T = 55 ºC
Standard Voltage
(Core 2 Duo-6M,
Celeron-2M)
35
17
1.86
3.82
1.42
2.94
Low Voltage
(Core 2 Duo -3M)
Intel® Core™ 2 Duo
Mobile Processors on 45-
nm process
Ultra Low Voltage
(Core 2 Duo -2M,
Celeron)
10
6.5
5.0
Notes:
1.
T is defined as the local (internal) ambient temperature measured approximately 1 inch upstream
A
from the device.
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Reference Thermal Solutions—Core™ 2 Duo Mobile Processors
6.0
Reference Thermal Solutions
Intel has developed reference thermal solutions designed to meet the cooling needs of embedded
form factor applications. This chapter describes the overall requirements for the reference thermal
solution including critical-to-function dimensions, operating environment, and verification criteria.
This document details solutions that are compatible with the AdvancedTCA* and Server System
Infrastructure (1U and larger) form factors.
The data in this section is based on wind tunnel testing of the reference thermal solutions. The
heatsinks were tested as an assembly with a thermal test vehicle (TTV), TIM, socket and test board.
The test assembly is placed in a rectangular duct with no upstream obstructions. Air flow is measured
by means of a calibrated nozzle downstream of the unit under test. The Ψ values shown in the charts
to follow represent the mean resistance values plus the one-sided, 99 percent confidence interval.
6.1
ATCA Reference Thermal Solution
for this form factor is 21.33 mm, so the maximum heatsink height is constrained to 16.27 mm. The
heatsink uses the fastener assembly to mount to the PCB as described in Section 6.6, “Heatsink
Figure 6.
AdvancedTCA* Reference Heatsink Assembly
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Core™ 2 Duo Mobile Processors—Reference Thermal Solutions
6.2
Keep Out Zone Requirements
The keep out zone requirements on the PCB to use this heatsink are detailed in Appendix B,
“Mechanical Drawings”. Because it extends beyond the footprint of the device, it is critical for the
board designer to allocate space on the board for the heatsink.
6.3
Thermal Performance
The AdvancedTCA reference heatsink is an all copper (C1100) design. The performance of this
heatsink has been tested at flow rates from 10 CFM to 30 CFM. The heatsink is expected to meet the
thermal performance needed when the air flow rate is at least 10 CFM at 40 °C. For an external
ambient of 55°C (ψ = 1.32 °C/W), this heatsink is expected to be suitable for air flow rates around
ja
15 CFM.
Figure 7.
AdvancedTCA* Heatsink Thermal Performance vs. Volumetric Airflow Rate
6.4
1U+ Reference Heatsink
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Reference Thermal Solutions—Core™ 2 Duo Mobile Processors
Figure 8.
1U Reference Heatsink Assembly
6.4.1
Keep Out Zone Requirements
The keep out zone requirements on the PCB to use this heatsink are detailed in Appendix B,
“Mechanical Drawings”. Because it extends beyond the footprint of the device, it is critical for board
designers to allocate space for the heatsink.
6.4.2
Thermal Performance
The 1U reference heatsink employs a thick copper (C1100) base with aluminum (Al 1050) stamped
fins, soldered to the base. The heatsink has been tested at flow rates from 10 CFM to 25 CFM. For a
40 °C external ambient and 35 W TDP, the heatsink is expected to meet the thermal performance
needed when the air flow rate is greater than 10 CFM. If the external ambient is 55 °C, this heatsink
will be suitable if the air flow rate is approximately 12 CFM or greater.
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Core™ 2 Duo Mobile Processors—Reference Thermal Solutions
Figure 9.
1U Heatsink Thermal Performance vs. Volumetric Airflow Rate
1U+ Reference Heatsink Performance
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Psi_ja
Psi_sa
0
5
10
15
20
25
30
Volumetric Air Flow Rate (CFM)
6.5
Compact PCI Reference Heatsink
Figure 10.
CompactPCI Reference Heatsink Assembly
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Reference Thermal Solutions—Core™ 2 Duo Mobile Processors
6.5.1
Keep Out Zone Requirements
The keep out zone requirements on the PCB to use this heatsink are detailed in Appendix B,
“Mechanical Drawings.” Because it extends beyond the footprint of the device, it is critical for board
designers to allocate space for the heatsink.
6.5.2
Thermal Performance
The cPCI reference heatsink is an all copper (C1100) design, intended for applications where vertical
space is limited. The heatsink has been tested at flow rates from 4 CFM to 24 CFM. For a 40 °C
external ambient and 17W TDP, the heatsink is expected to meet the thermal performance needed
when the air flow rate is at least 4 CFM.
Figure 11.
cPCI Reference Heatsink Thermal Performance vs. Volumetric Flow Rate
6.6
Heatsink Fastener Assembly
The reference solutions use a screw, spring, and back plate assembly to attach the heatsink to the
PCB. The fastener assembly used on the reference heatsink must apply the load conditions described
the keep out zone requirements described in this document, and should not degrade the thermal
performance of the reference heatsinks. Finally the fastener assembly should be designed to meet the
6.7
Thermal Interface Material (TIM)
The thermal interface material provides improved conductivity between the die and heatsink. It is
important to understand and consider the impact of the interface between the die and heatsink base
to the overall thermal solution. Specifically, the bond line thickness, interface material area, and
interface material thermal conductivity must be selected to optimize the thermal solution.
It is important to minimize the thickness of the thermal interface material (TIM), commonly referred
to as the bond line thickness. A large gap between the heatsink base and the die yields a greater
thermal resistance. The thickness of the gap is determined by the flatness of both the heatsink base
and the die, plus the thickness of the thermal interface material, and the clamping force applied by
the heatsink attachment method. To ensure proper and consistent thermal performance, the TIM and
application process must be properly designed.
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Core™ 2 Duo Mobile Processors—Reference Thermal Solutions
Thermal interface materials have thermal impedance (resistance) that will increase as the material
degrades over time. It is important for thermal solution designers to take this increase in impedance
into consideration when designing a thermal solution. It is recommended that system integrators
work with TIM suppliers to determine the performance of the desired thermal interface material. If
system integrators wish to maintain maximum thermal solution performance, the TIM could be
replaced during standard maintenance cycles.
The reference thermal solution uses Shin Etsu* G751. Alternative materials can be used at the user’s
discretion. Regardless, the entire heatsink assembly, including the heatsink, and TIM (including attach
method), must be validated together for specific applications.
6.8
Heatsink Orientation
All of the heatsinks were designed to maximize the available space within the volumetric keep out
zone and their respective form factor limitations. These heatsinks must be oriented in a specific
direction relative to the processor keep out zone and airflow. In order to use these designs, the
processor must be placed on the PCB in an orientation so the heatsink fins will be parallel to the
Figure 12.
Heatsink Orientation Relative to Airflow Direction
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Thermal Metrology—Core™ 2 Duo Mobile Processors
7.0
Thermal Metrology
The system designer must make temperature measurements to accurately determine the
performance of the thermal solution. Validation of the processor’s thermal solution should be done
using a thermal test vehicle (TTV). The TTV allows for an accurate junction temperature measurement
as well as input power control. For more information, contact your Intel field sales representative.
In addition, the processor’s heatsink should be verified in a system environment. Intel has established
Measurements” provides guidelines on how to accurately measure the component temperature.
that will emulate anticipated maximum thermal design power.
7.1
Die Temperature Measurements
The component T
must be maintained at or below the maximum temperature specification as
JUNCTION
temperature is to use the Digital Thermal Sensor as described in the processor’s datasheet. Refer to
the processor datasheet for more information on the DTS.
The legacy on-board thermal diode is not recommended for performing heatsink validation. The
thermal diode is suitable for long term trending data, but is not a reliable indicator of the processor’s
temperature.
7.2
Power Simulation Software
The power simulation software is a utility designed to dissipate the thermal design power on a
processor. To assess the thermal performance of the processor thermal solution under “worst-case
realistic application” conditions, Intel is developing a software utility that operates the processor at
near worst-case power dissipation.
The power simulation software should only be used to test customer thermal solutions at or near the
thermal design power. For power supply current, please refer to each component’s datasheet for the
I
(Max Power Supply Current) specification. For information on how to obtain the maximum power
CC
program, contact your Intel field sales representative.
7.3
Additional Thermal Features
®
The Intel Core 2 Duo processor supports other thermal features including the Intel Thermal Monitor,
PROCHOT#, FORCEPR#, and THERMTRIP# signal pins. Details for using these features are contained
in the processor datasheet.
7.4
Local Ambient Temperature Measurement Guidelines
The local ambient temperature (T ) is the temperature of the ambient air surrounding the processor.
LA
For a passive heatsink, T is defined as the heatsink approach air temperature; for an actively cooled
A
heatsink, it is the temperature of inlet air to the active cooling fan.
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Core™ 2 Duo Mobile Processors—Thermal Metrology
It is worthwhile to determine the local ambient temperature in the chassis around the processor to
understand the effect it may have on the case temperature. T is best measured by averaging
LA
temperature measurements at multiple locations in the heatsink inlet airflow. This method helps
reduce error and eliminate minor spatial variations in temperature. The following guidelines are
meant to enable accurate determination of the localized air temperature around the processor during
system thermal testing.
7.4.1
Active Heatsink Measurements
• It is important to avoid taking measurements in the dead flow zone that usually develops above
the fan hub and hub spokes. Measurements should be taken at four different locations uniformly
placed at the center of the annulus formed by the fan hub and the fan housing to evaluate the
uniformity of the air temperature at the fan inlet. The thermocouples should be placed
approximately 3 mm to 8 mm [0.1 to 0.3 in.] above the fan hub vertically and halfway between
• Using an open bench to characterize an active heatsink can be useful, and usually ensures more
uniform temperatures at the fan inlet. However, additional tests that include a solid barrier above
the test motherboard surface can help evaluate the potential impact of the chassis. This barrier is
typically clear Plexiglas*, extending at least 100 mm [4 in.] in all directions beyond the edge of
the thermal solution. Typical distance from the motherboard to the barrier is 81 mm [3.2 in.]. If a
barrier is used, the thermocouple can be taped directly to the barrier with clear tape at the
horizontal location as previously described, halfway between the fan hub and the fan housing.
• For even more realistic airflow, the motherboard should be populated with significant elements
like memory cards, graphic card, and chipset heatsink. If a variable speed fan is used, it may be
useful to add a thermocouple taped to the barrier above the location of the temperature sensor
used by the fan to check its speed setting against air temperature. When measuring T in a
LA
chassis with a live motherboard, add-in cards, and other system components, it is likely that the
T
measurements will reveal a highly non-uniform temperature distribution across the inlet fan
LA
section.
Note:
Testing an active heatsink with a variable speed fan can be done in a thermal chamber
to capture the worst-case thermal environment scenarios. Otherwise, when doing a
bench top test at room temperature, the fan regulation prevents the heatsink from
operating at its maximum capability. To characterize the heatsink capability in the
worst-case environment in these conditions, it is then necessary to disable the fan
regulation and power the fan directly, based on guidance from the fan supplier.
7.4.2
Passive Heatsink Measurements
• Thermocouples should be placed approximately 13 mm to 25 mm [0.5 to 1.0 in.] away from
• The thermocouples should be placed approximately 51 mm [2.0 in.] above the baseboard. This
placement guideline is meant to minimize the effect of localized hot spots from baseboard
components. The height above the board may vary depending on the height of the thermal
solution and form factor.
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Reliability Guidelines—Core™ 2 Duo Mobile Processors
8.0
Reliability Guidelines
Each motherboard, heatsink, and attach combination may vary the mechanical loading of the
component. The user should carefully evaluate the reliability of the completed assembly prior to use
Table 4.
Reliability Requirements
1
2
Test
Requirement
Pass/Fail Criteria
Visual Check and Electrical
Functional Test
Mechanical Shock
Random Vibration
Temperature Life
50 g, board level, 11 msec, 3 shocks/axis
Visual Check and Electrical
Functional Test
7.3 g, board level, 45 min/axis, 50 Hz to 2000 Hz
85 °C, 2000 hours total, checkpoints at 168, 500,
1000, and 2000 hours
Visual Check
Thermal Cycling
Humidity
-5 °C to +70 °C, 500 cycles
Visual Check
Visual Check
85% relative humidity, 55 °C, 1000 hours
Notes:
1.
The above tests should be performed on a sample size of at least 12 assemblies from three lots of
material.
Additional pass/fail criteria may be added at the discretion of the user.
2.
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Core™ 2 Duo Mobile Processors—Thermal Solution Component Suppliers
Appendix A Thermal Solution Component Suppliers
These vendors and devices are listed by Intel as a convenience to Intel’s general customer base. Intel
does not make any representations or warranties whatsoever regarding quality, reliability,
functionality, or compatibility of these devices. This list and/or these devices may be subject to
change without notice.
Note:
The enabled components may not be currently available from all suppliers. Contact the
supplier directly to verify availability.
Table 5.
Reference Heatsink
Part
Part Number
Contact Information
AdvancedTCA* passive heatsink assembly
1U+ passive heatsink assembly
ECC-00177-01-GP
ECC-00179-01-GP
ECC-00178-01-GP
Cooler Master*
Wendy Lin
(510)770-8566 ext 211
cPCI passive heatsink assembly
Honeywell*
Paula Knoll
(858) 279-2956
Thermal Interface Material
PCM45F
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