I'm trying to drive this piezo element at 40 kHz but am running into troubles when using a function generator since the element requires greater drive.

I got the guts of an ultrasonic cleaner to drive the element, but it was modulating at about 10 kHz.

Could anyone give advice on how to drive the element?

I also can't derive what voltage it wants to be driven at, either.

  • \$\begingroup\$ It is an 8 Ohm speaker rated for 50W. So, around 20V RMS maximum. \$\endgroup\$ – JRE Aug 6 '19 at 14:08
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    \$\begingroup\$ I just drove it with a function generator through an L293D H bridge at 24Vpp Then you drove it with a square wave (not a sine-wave). Square waves have the property that they contain lots of harmonic frequencies which can destroy a tweeter, as you discovered. Also, the power rating might not be exactly what is listed in the specs. The rating might be a peak rating meaning, it can handle that power for a very short time only. Any way, don't use the L293 for audio, it is designed to drive a motor. Same as you should not use an audio amplifier to power a motor. \$\endgroup\$ – Bimpelrekkie Aug 6 '19 at 14:55
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    \$\begingroup\$ I suggest that you educate yourself on speakers, audio signals etc, basically all that is involved because if you don't and do more or less the same to a different tweeter, that tweeter will also be destroyed (I guarantee it). The speakers simply cannot handle the amount of power you feed them. \$\endgroup\$ – Bimpelrekkie Aug 6 '19 at 15:04
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    \$\begingroup\$ @Orbitronics: The signal generator was putting out a sine wave. The 293 was making nice, sharp, vicious square waves out of your sine wave. \$\endgroup\$ – JRE Aug 6 '19 at 16:43
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    \$\begingroup\$ Also, 50W is the maximum. You want to stay well under that. \$\endgroup\$ – JRE Aug 6 '19 at 16:49

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