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Questions relating to designing PCBs
By genifycom
#192503
Forgive my ignorance please. If I look at QFN-16 ICs, there are (at a minimum) two different pin layouts. A 4 pins per side arrangement and a 2x5 and 2x3 pin arrangement.

What is the industry standard to distinguish between these two?

I ask because parts.io lists my IC as "Package Description VQCCN, LCC16,.12SQ,20". NXP lists it as Case 2094-01. Searches seem to show that these are manufacturer or distributor specific.

When looking for an adapter, they all just list QFN-16 (3 x 3 mm body, 0.5 mm pin pitch) which could be either pin arrangement.

Thank you for any guidance.
By FredC
#192970
QFNs are usually complicated because their connections are usually at the bottom of the chip.
By n1ist
#192977
I have only seen the 4x4 arrangement. I'd guess a 3x3mm body would be for the 4x4 pad version and the other version would be a rectangular package.
/mike
By mattylad
#192996
Unfortunately the manufacturers rarely standardize.

Take SOT23 for instance, there are about 50+ variations on it.

Take your parts datasheet, enter the component dimensions into the PCB libraries Library Expert and produce a footprint for your CAD package. The free version should enable you to do this quickly and easily.
By FredC
#193034
mattylad wrote:Unfortunately the manufacturers rarely standardize.

Take SOT23 for instance, there are about 50+ variations on it.

Take your parts datasheet, enter the component dimensions into the PCB libraries Library Expert and produce a footprint for your CAD package. The free version should enable you to do this quickly and easily.
Good idea. A free version will simplify the process for you. But in the datasheet some revisions may differ depending on the current version.