Thermal Characteristics of 16- and 40-Pin Plastic DIP's

The thermal performance of 16- and 40-pin plastic dual in-line packages (DIP's) is described in light of current trends towards higher device powers and ambient temperatures. Extensive experimental and computer modeling studies on both package types have revealed that extraordinary improvements in thermal characteristics can result from proper selection of package materials and cooling parameters. In particular, judicious choices of leadframe material, molding compound, heatspreader, and mode of external cooling can lead to excellent thermal performance. To accomplish this, component manufacturers and system users must work closely to properly select materials and conditions to maximize effectiveness. In the best case, thermal resistances of 38°C/W and 26°C/W were found for 16- and 40-pin plastic DIP's using forced air cooling. The importance of both device power level and board temperature rise above ambient on
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is discussed in some detail. Suggestions are made to both component manufacturers and system users on how to minimize variations in measured
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.