Passive Buzzer KY-006 - wiring

I have a KY-006 buzzer at home which works fine. I would like to solder it off the PCB and put it on my own board. I still couldn't figure out the following though:

  • Usually you leave the VCC pin (middle pin) free. I found some wiring plots though especially for raspberry where this pin is connected though. Why is this? What does this do?

  • How is the wiring on the pcb itself? (can not see it properly) It looks like the buzzer has only 2 pins. On the PCB are no other electronic parts, so it simply does not make much sense to me. Maybe I have overlooked something?

Thanks a lot!

From what I can find of the KY-006 module, Vcc pin is not connected to anything. You should be able to unsolder the buzzer and put it on your board. Just connect the ground and the signal (+) terminals.

No, it is not easy, nor well shown on most Web photos.

The actual piezo has only two pins and there is no other component on the PCB so indeed the centre - VCC - pin is not connected. There are also a couple of different versions of the PCB which is clearly also designed to accommodate two different purposes.

The three pin arrangement is purely to facilitate a modular system where different modules use a system common to servos with readily available three wire cables to connect to "expansion shields". Note that there are two alternate (incompatible) pin arrangements for servo connectors. :roll_eyes:

Possibly the Raspberry Pi arrangement you cite is using a corresponding expansion shield.