Intel 631xESB, 632xESB manual Mechanical Interface Material, Thermal Interface Material

Intel® 6321ESB ICH—Reference Thermal Solution

Figure 12. Torsional Clip Heatsink Assembly

7.5.2Mechanical Interface Material

There is no mechanical interface material associated with this reference solution.

7.5.3Thermal Interface Material

A Thermal Interface Material (TIM) provides improved conductivity between the die and heatsink. The reference thermal solution uses Honeywell* PCM45F, 0.254 mm (0.010 in.) thick, 15 mm x 15 mm (0.59 in. x 0.59 in.) square.

Note: Unflowed or "dry" Honewell PCM-45F has a material thickness of 0.010 inch. The flowed or "wet" Honeywell PCM-45F has a material thickness of ~0.003 inch after it reaches its phase change temperature.

7.5.3.1Effect of Pressure on TIM Performance

As mechanical pressure increases on the TIM, the thermal resistance of the TIM decreases. This phenomenon is due to the decrease of the bond line thickness (BLT). BLT is the final settled thickness of the thermal interface material after installation of heatsink. The effect of pressure on the thermal resistance of the Honeywell PCM45 F TIM is shown in Table 5.

Intel provides both End of Line and End of Life TIM thermal resistance values of Honeywell PCM45F. End of Line and End of Life TIM thermal resistance values are obtained through measurement on a Test Vehicle similar to the Intel® 631xESB/ 632xESB I/O's physical attributes using an extruded aluminum heatsink. The End of Line value represents the TIM performance post heatsink assembly while the End of

Intel® 631xESB/632xESB I/O Controller Hub for Embedded Applications

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