Design Guide 77
Intel® 31244 PCI-X to Serial ATA Controller
Thermal Solutions
Thermal Solutions 15
GD31244 is packaged in a 17 mm, 256-pin Plastic Ball Gri d Arra y (PBGA) in an indu stry-sta ndard
footprint. The package includes a four layer substrate with power and ground planes. The
construction of the package is shown below. The device is specified for operation when TC (case
temperature) is within the range of 0o C to 90o C, depending on the operating conditions. Refer to
Figure 3 for a details on the package.

15.1 Thermal Recommendations

Based on data Intel gathered while performing thermal validation, the GD31244 does not require a
heat sink. The tests were performed in an environment with no airflow, an ambient temperature of
60° C with the processor executing a maximum power test. However, when the case temperature
(108° C) is exceeded, a passive heat sink may be used.
Table 37. Thermal Resistance
Symbol De scription Value Units
TAStill air ambient temperature to meet maximum case temperature
specifications: [ TA = TC - (PDMAX-θca)] 70 oC
θca Thermal resistance from case to ambien t in still air includ ing
conduction throug h the leads 20 oC/Watt
Table 38. 544-Lead H-PBGA Package Thermal Characteristics
Thermal Resistance - oC/Watt
Parameter Airflow - ft/min. (M./sec .)
0 100 200 400 600
θca
Thermal Resistance fro m case to Ambient 20 12.5 11.2 10.2 9.2