Hi MM, I used a 'burst' method of driving 200KHz and 30KHz transducers. The transducer pulse generator was from a square wave osc, tunable over a narrow range in order to get the optimum power out from the transducer. The pulse or burst width generator was adjustable from 100uSec thru 10mSec, this enabled a level of power control in the acoustic pulse. The transducer driver stage was a NPN power transistor driving a 1:3 or 1:5 transformer at 30KHz or 200KHz respectively, supply voltage 12V or 24V depending upon the required acoustic power. My product applications were for hydro-graphic depth echo sounders, working in water depths of 0.5mtr upto 400mres.

E Is you application bio-diesel.? Hi Eric, Isn't the number of cycles (burst) of 40khz determined by the length of the ON pulse? A 20ms pulse will have more cycles that a 2ms one (10 times more).

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Jan 28, 2016 - Building driving circuit for ultrasonic transducer - 100khz 60W. I would advise you to use a transformer and a push-pull amplifier FET. The driver includes the five additional inverters of IC 1, IC 1B through IC 1F.A voltage tripler comprises diodes D 1 and D 2 and the surrounding components. The amplifier comprises Q 2, and the piezoelectric driver comprises Q 1 and Q 2.

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The size of the Burst is directly related to the duty cycle. In order to increase the burst time, we need an amplifier that will take more power. Currently I can't get past a duty cycle of 1% without smoking the heatsinked Fet. EG: 5ms ON and 500mx OFF. As I mentioned before, I dip all transducers to find their exact resonant TX frequencies and their band pass. Then I program the CPU to change frequency over the band pass. If the BP is say 2khz wide, I will step the frequency up by 100hz every few seconds.

That way I send multiple bursts to 20 different frequency locations, of which a few should be more effective in ringing the wafer. What do you think? I built a cat scarer at my last house.

I didn't bother with trying to tune to the ultrasonic horn I had. I drove the secondary of a toroidal mains transformer using a low voltage drive at ~41KHz and used the primary straight across the piezo horn. Maybe not the most efficient, but it worked effectively and gave quite a nip when touched. What surprised me most was the frequency response of a 6.0.6-240VAC cheapo toroid was at such a frequency.

It solved my cat problem BTW with me having to suffer the loud click when the device first powered the horn. I could have resolved this with a bit of signal/startup logic but never bothered in the end.

My project needs to drive a medium power ultrasonic piezoelectric transducer from a sine wave ( / sawtooth) sweep generator that sweeps +/- 2% of the transducer resonant frequency. The question: What are my simplest options for driving these transducers from a DDS generated shaped signal, with reasonably low distortion (5-10%)? • Use a power amplifier IC off a higher voltage rail, with lots of heat sinking, to directly drive the transducer • Use a power amplifier IC, then (?) a transistor current amplification stage, then an appropriate (need help identifying) step-up transformer to drive the transducer • Use some sort of (need help identifying) class D high power amplifier IC that would not need much heat sinking ( Edit: Not a solution, see Note 7). • Some other option entirely • Edit: From suggestion below Identify an off the shelf OEM amplifier module that meets the parameters and constraints. UPDATE: [15-Oct-2012] Option 5 above seems best answer, if a suitable OEM module or two could be pointed out - None found in my research so far.

Hence leaving question open. The sweep waveform generation is through a DDS IC, AD9850, Datasheet here: One of the transducers available to me: 5938D-25LBPZT-4 () • Resonant frequency: 25 KHz • Resonant impedance: 10-20 Ohms • Capacitance: 5400 pf +/-10% • Input power: 60W • Datasheet: I wish I could find one! The transducer would change case to case, from 20KHz to 135KHz, each in the 50-250 watt range, similar in design to the one above. The driver designs I have seen for these transducers typically use switching i.e. Square waves to drive them, MOSFET driven, with Vpp 100v in some cases! ( Do these devices even need that kind of voltage?