Driving piezo speakers in the simplest manner

Question

I have a few options for the frequency generator side (25-35 Khz). Namely the NE555 or Arduino are some options. These outputs are minimal and I intend to drive the piezo X 4 V_p-p 12 V. Is the MOSFET the best option on this side? Please any information would be appreciated. I am from a electrical background and trying to learn electronics so excuse my ignorance.

Answer 1

I don't know the capacitance of your piezo, but you can abuse a MOSFET gate driver with one inverted and one non inverted output for a start.
The 12 V supply will provide the required Vpp level at the piezo.
R1 limits the peak current and is just a guess.
Some motor driver chips like DRV8220 can handle these frequencies as well.

^{simulate this circuit – Schematic created using CircuitLab}

Another approach uses a tapped inductor or transformer. The output voltage can be contolled by variations of the signal generator duty cycle, values up to 50% are useful.
However, the resonance frequency of transformer inductance and piezo capacitance should match the input frequency. So this circuit can not be used if a wide frequency range is required.
Do not use this circuit without a connected piezo. High drain voltage peaks can destroy the MOSFET in this case.

^{simulate this circuit}

Finally an old school CMOS multivibrator with BJT bridge:

^{simulate this circuit}