What are the dents for?

Question

I bought a few bc417 serial Bluetooth modules which have pins that look like this:

pad specification

Is there a standard name for this kind of pin? I believe I can treat them like any other SMD pin, but I'm curious what the dents are for. Are they intended for a header pin to go there somehow? Just keeping your iron from slipping? Something else? What's the recommend way to attach these to a board?

Related question, which features castellations heavily: [Soldering PCBs directly together](http://electronics.stackexchange.com/q/35625/7036) — Nick Alexeev, Mar 07 '15 at 19:00

score 14 · Accepted Answer · answered Mar 07 '15 at 16:59

14

Those are castellations. They provide a larger surface area for the solder to wet when the module is surface-mount soldered to another board. They can be used to hold a pin in order to convert the module into a through-hole device, but such a practice is rarely done.

answered Mar 07 '15 at 16:59

Ignacio Vazquez-Abrams

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...unless you are a hobbyst that uses breadboards :P +1 – Vladimir Cravero Mar 07 '15 at 20:36
Only if the module has 2.54mm centers on opposite sides. – Ignacio Vazquez-Abrams Mar 07 '15 at 20:46

What are the dents for?

1 Answers1