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I'm tying to drive a "Moisturizing Transducer Mist Maker Atomizer Film Plate" using a simple astable multivibrator circuit like this:

enter image description here

I can't make it work. No reaction from the atomizer. I checked and fine-tuned the frequency exactly:

enter image description here

Parameters of the atomizer:

Specifications:
Type: Atomizer Film Plate 
Diameter:16mm
Color: white
Driving Voltage:DC 3-12V
Power:2.5W max.(Normal use 1.5W)
Resonant frequency: 108.0±5.0kHz
Resonant Impedance: 150Ωmax
Input voltage: 5～13V DC
Rated Voltage: 70Vp-p max
Service Life:>3000h
Atomization Amout: 50～100ml/hour
Cord length: 80mm

Why does frequency changes after connecting the atomizer? Without it I had 108 kHz, after connecting it risen to 120 kHz, so I had to add additional resistors to decrease it to 108 kHz again. What is causing this?

I also tried to connect it in series with transistor, hoping that series resonance will make it work.

enter image description here

No result with that, either. I also tried supply voltage of 9V, to no effect.

What am I missing here?

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    \$\begingroup\$ Might this provide the clue: Driving Voltage:DC 3-12V or maybe this: Input voltage: 5～13V DC then, just to confuse things it says this: Rated Voltage: 70Vp-p max so, given that I've pulled all that from your question, can you see how confusing the information you have provided is. Try and find a data sheet for the pizeo part. If you can't find one then you probably won't get anything other than bad guesses on this site. \$\endgroup\$
    – Andy aka
    Commented Oct 10, 2021 at 15:14
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    \$\begingroup\$ The transistors are backwards, the emitters should connect to the positive battery terminal and the battery should have a capacitor parallel with it. \$\endgroup\$
    – Audioguru
    Commented Oct 10, 2021 at 15:30
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    \$\begingroup\$ Piezo transducers usually require rather high voltages. If you're feeding it with just 5 V, I wouldn't expect it to do much. \$\endgroup\$
    – Hearth
    Commented Oct 10, 2021 at 17:16
  • \$\begingroup\$ @Audioguru Transistors are PNP not NPN. \$\endgroup\$
    – ScienceDiscoverer
    Commented Oct 11, 2021 at 4:27
  • \$\begingroup\$ @Hearth Hm, its strange, coz I looked at driving voltage/input voltage that said 5-12 V and thought its gonna suffice... Its rather confusing specs, indeed. Maybe they put in specs for store's own driver? Although its just the piezo element itself. \$\endgroup\$
    – ScienceDiscoverer
    Commented Oct 11, 2021 at 4:29

1 Answer 1

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The problem is ambiguous product description provided by the seller. It lists "input voltage" and "operating voltage", but this value is listed for their own driver circuit that works with this transducer. Why they listed it on the page for buzzer only, I have no idea.

Here is good video to better understand how this thing is suppose to work.

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