2.2.1 Package Thermal Characteristics
The device junction-to-case thermal characteristic is θjc, and the junction-to-ambient air characteristic is θja. The thermal characteristics for θja are shown with two different air flow rates. θjc values are provided for reference. The absolute maximum junction temperature is 125 °C.
The maximum power dissipation allowed for commercial and industrial grade devices is a function of θja. A sample calculation of the absolute maximum power dissipation allowed for an 896-pin FBGA package at commercial temperature and still air is as follows:
The maximum power dissipation allowed for military temperature and Mil-Std 883B devices is specified as a function of θjc.
The following table lists the package thermal characteristics.
| Package Type | Pin Count | θjc | θja Still Air | θja 1.0m/s | θja 2.5m/s | Units |
|---|---|---|---|---|---|---|
| Chip Scale Package (CSP) | 180 | N/A | 57.8 | 51.0 | 50 | °C/W |
| Plastic Quad Flat Pack (PQFP) | 208 | 8.0 | 26 | 23.5 | 20.9 | °C/W |
| Plastic Ball Grid Array (PBGA) | 729 | 2.2 | 13.7 | 10.6 | 9.6 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 256 | 3.0 | 26.6 | 22.8 | 21.5 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 324 | 3.0 | 25.8 | 22.1 | 20.9 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 484 | 3.2 | 20.5 | 17.0 | 15.9 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 676 | 3.2 | 16.4 | 13.0 | 12.0 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 896 | 2.4 | 13.6 | 10.4 | 9.4 | °C/W |
| Fine Pitch Ball Grid Array (FBGA) | 1152 | 1.8 | 12.0 | 8.9 | 7.9 | °C/W |
| Ceramic Quad Flat Pack (CQFP)1 | 208 | 2.0 | 22 | 19.8 | 18.0 | °C/W |
| Ceramic Quad Flat Pack (CQFP)1 | 352 | 2.0 | 17.9 | 16.1 | 14.7 | °C/W |
| Ceramic Column Grid Array (CCGA)2 | 624 | 6.5 | 8.9 | 8.5 | 8 | °C/W |
- θjc for the 208-pin and 352-pin CQFP refers to the thermal resistance between the junction and the bottom of the package.
- θjc for the 624-pin CCGA refers to the thermal resistance between the junction and the top surface of the package. Thermal resistance from junction to board (θjb) for CCGA 624 package is 3.4 °C/W.