Hot rods keep the die cool
Quad Flatpack No leads (QFN) packages offer at least one advantage over Ball Grid Array (BGA) packages: because the electrical connections are partly made via solder lands on the side of the component visual inspection of solder joints and repairing them is easier. Thermally enhancing a package for power applications can be done with a heat conducting pad underneath, but this makes visual inspection difficult. Fortunately other solutions exist.
Texas Instruments’ HotRod QFN is a thermally enhanced plastic package with solder lands on all sides as well as power buses for enhanced current carrying capability. Inside the package the die is mounted on a copper lead frame which eliminates the power wire bonds, improving electrical and thermal performance. This technique also improves application efficiency and minimizes package parasitic radiation.
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