Datasheet

MPC8241 Integrated Processor Hardware Specifications, Rev. 10
Freescale Semiconductor 47
System Design Information
7.7 Thermal Management
This section provides thermal management information for the plastic ball grid array (PBGA) package for
air-cooled applications. Depending on the application environment and the operating frequency, a heat
sink may be required to maintain junction temperature within specifications. Proper thermal control design
primarily depends on the system-level design: heat sink, airflow, and thermal interface material. To reduce
the die-junction temperature, heat sinks can be attached to the package by several methods: adhesive,
spring clip to holes in the printed-circuit board or package, or mounting clip and screw assembly (see
Figure 28).
Figure 28. Package Exploded Cross-Sectional View with Several Heat Sink Options
Figure 29 depicts the die junction-to-ambient thermal resistance for four typical cases:
• A heat sink is not attached to the PBGA package and a high board-level thermal loading from
adjacent components exists (label used—1s).
• A heat sink is not attached to the PBGA package and a low board-level thermal loading from
adjacent components exists (label used—2s2p).
• A large heat sink (cross cut extrusion, 38 × 38 × 16.5 mm) is attached to the PBGA package and a
high board-level thermal loading from adjacent components exists (label used—1s/sink).
• A large heat sink (cross cut extrusion, 38 × 38 × 16.5 mm) is attached to the PBGA package and a
low board-level thermal loading from adjacent components exists (label used—2s2p/sink).
Adhesive or
Thermal Interface
Heat Sink
PBGA Package
Heat Sink
Clip
Printed-Circuit Board
Option
Material
Die
Wire