Intel CORETM 2 DUO MOBILE 320028-001 - Manual (Page 11)

Core™ 2 Duo Mobile Processors—Mechanical Specifications
Intel® Core™ 2 Duo Mobile Processors on 45-nm process-Thermal Design Guide
TDG June 2008
11 Order Number: 320028-001
4.0 Mechanical Specifications
4.1 Package Mechanical Requirements
4.1.1 Die Pressure/Load Upper Limit
From a die mechanical integrity standpoint, the maximum allowable normal die load is the lesser of
15 lbs or 100 psi. Considering the 15 lbs load limit and the nominal die area of 1.45 cm 2 (0.22 in. 2 ),
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
0.30 o C-cm 2 /W.
4.2 Package Keep Out Zones Requirements
The heatsink must not touch the package in the areas shown in Figure 2 and Figure 4 . The heatsink
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
solutions are shown in Figure 2 and Figure 3 . Detailed drawings for the PCB keep out zones are in
Appendix B .
Components placed between the underside of the heatsink and motherboard cannot exceed 4.75 mm
in height when using heatsinks that extend beyond the socket envelope shown in Figure 2 for the
micro-FCPGA package.