[Andy B. Gam]

Hi all;

We are using a QFN package in our application, it’s relatively high volume targeting CE devices, the packaging supplier is asking if punched QFN is acceptable package for our application, can someone elaborate the different?

Any help is really appreciated!

Andy

[Andy Longford]

The punch method of singulation is a similar process to the singulation used on DIP and SOIC packages. It is normally only used where the overmolded part of the QFN is individual, and the leadframe is exposed between adjacent units.
The typical high volume assembly process for QFN employs a “block” overmold format. For these the best method of singulation is by use of a Dicing Saw.