Intel Xeon processor LV Thermal Design Guide

Reference Thermal Solutions
Dual-Core Intel
®
Xeon
®
processor LV and ULV
Thermal Design Guide August 2006
26 Reference Number: 311374-002
6.3.1 Mechanical Design
The AdvancedTCA reference thermal solution is shown in Figure 14. The maximum
component height 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 (refer to
Section 6.2) to mount to the PCB. Detailed drawings of this heatsink are provided in
Appendix B, “Mechanical Drawings”.
6.3.2 Keep-Out Zone Requirements
The keep-out zone requirements on the PCB to use this heatsink are detailed in
Appendix A, “Reference Heatsink”. It is critical for the board designer to allocate space
on the board for the heatsink since it extends beyond the footprint of the socket.
6.3.3 Thermal Performance
The AdvancedTCA reference heatsink should be made from copper to achieve the
necessary thermal performance. Based on the boundary conditions stated (ambient
temperature = 40 °C), the heatsink will meet the thermal performance needed to cool
both the 15 W and 31 W processor in the AdvancedTCA form factor. The heatsink
performance versus volumetric airflow rate is shown in Figure 15.
The system integrator can make trade-offs to determine the best heatsink material to
use based on usage conditions. For example, a higher ambient temperature might be
considered with use of the copper heatsink.
Figure 14. AdvancedTCA* Reference Heatsink Assembly
*