Revision 1.15 – August 30, 2007
440GX – Power PC 440GX Embedded Processor
Data Sheet
Heat Sink Mounting Information (Ceramic Package Only)
Proper thermal design is primarily dependent upon multiple system-level effects; that is, the effects of the heat
sink, the air flow, and the thermal interface material. To reduce the die-junction temperature, heat sinks may be
attached to the package by several methods: adhesive, spring clips to the printed-circuit board or package, or a
mounting clip and screw assembly. When attaching heat sinks, it is important to avoid placing excessive
mechanical stress on bonding of the chip to the substrate and the package to the board.
Heat Sink Attached With Spring Clip
Heat sink
Heat sink
Heat sink clip
Heat sink clip
Thermal grease
Thermal grease
CBGA
CBGA
package
package
Printed
circuit
board
Printed
circuit
board
Spring clip to package
Spring clip to board
1
Static compression (spring force)—2.27kg maximum
Static compression (spring force)—2.27kg maximum
Note 1: Force is limited by allowable compression on the die.
Allowable package compression force is 4.4kg.
Heat Sink Attached With Adhesive
Heat sink
Adhesive
Printed
circuit
board
CBGA
CBGA
package
package
Adhesive
Printed
circuit
board
Heat sink
Weight
force
Weight
force
Heat sink weight force—60g maximum
Important: All of the guidelines indicated in the above diagrams must be evaluated and adjusted to account for the
shock and vibration effects of any particular application.
60
AMCC
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
