Electronic – THT: What is a squared annular “ring”?


At least in KiCad, the footprints of through-hole pin headers have one squared annular “ring”, the other ones are round:

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What does the square indicate?

(Also I’m wondering if there is perhaps a convention of connecting GND to it.)

Best Answer

It’s just a quick and easy way to distinguish which connector pad is pin 1.

Particularly when there is no silkscreen present or just when routing the PCB.