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I have a QFN part that contains exposed pins on the side (in addition to the bottom). It looks like the quantity and spacing of the side pins are perfectly matched with the bottom pins, except there are a couple little smaller pins in the corner. Here is an image of the side view:

enter image description here

What is the purpose of these? I'm kind of hoping I can solder to the side pins instead of the bottom pins since it's sometimes hard for me to tell if the bottom pins are shorted/open

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    \$\begingroup\$ QFN packages aren't for soldering with a soldering iron. They are intended for a reflow process, and you can use a hot air station for hand-soldering. \$\endgroup\$
    – Olin Lathrop
    Commented Nov 17, 2016 at 23:25
  • \$\begingroup\$ youtube.com/watch?time_continue=225&v=c_Qt5CtUlqY \$\endgroup\$
    – D.A.S.
    Commented Nov 17, 2016 at 23:54
  • \$\begingroup\$ I have not seen a QFN package where the side-cut exposed end was not a continuation of the bottom pads. I don't believe this isolation (as shown on the drawings) is technologically possible.Which exactly chip is this? \$\endgroup\$
    – Ale..chenski
    Commented Nov 18, 2016 at 3:19
  • \$\begingroup\$ silabs.com/Support%20Documents/TechnicalDocs/EFM32ZG108.pdf \$\endgroup\$
    – user2913869
    Commented Nov 18, 2016 at 14:26

1 Answer 1

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When the die was attached to the leadframe and the epoxy encapsulant was molded over it, the leadframe was still connected to a larger structure (and probably to an array of other die locations).

The metal you see from the side of the package is where the leadframe was sheared of to separate this particular package from the others.

enter image description here

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