Driving 3 pin piezo buzzer?

[hal9001]

I found a 3 pin buzzer with labels F, M, G for pins. What do those letter mean? Can I drive it like a 2 pin buzzer with one pin to positive rail and another to a FET driving a square wave to ground? Will the RE46C100 drive it louder than just a FET?

Cheers!

[Zero999]

I found a 3 pin buzzer with labels F, M, G for pins. What do those letter mean?

Feedback, Main and Ground.

Can I drive it like a 2 pin buzzer with one pin to positive rail and another to a FET driving a square wave to ground?

Yes that will work, although it's piezo and therefore capacitive, so it will be louder when driven straight off the output off a microcontroller, assuming the voltage is equal. If you need to drive it at a higher voltage, with a transistor, then you need a resistor in parallel, to discharge the capacitance.

Will the RE46C100 drive it louder than just a FET?

Cheers!

Yes, that IC will drive it louder because it has a push-pull output and drives it at the resonant frequency.

[ArdWar]

One simple and cheap way to drive piezo is to bridge it across two out of phase GPIO, or across inverting buffers if there's concern with uC max output current.

3 terminal piezo buzzer adds an additional feedback pin that usually used to implement self resonant oscillator drive. Driving the piezo at its peak efficient frequency. It's optional, you can still drive it the "brute force" way ignoring the feedback pin.