Hi, i tried the circuit and used a ESP32 board to provide 1.7mhz pwm. The peizo disc is resonant at 1.7mhz and used as humidifier/ perfume dispenser. I can get vibrations but very weak. And within seconds the MOSFET gets damaged. I am running inductor boosted circuit at 24v and mosfet is 150v 44a capable.
I don't think I mentioned a sine wave in this video. Can you reference a time stamp? What the video demonstrate is a simple method to produce 20V square wave at ultrasonic frequencies (up to 100kHz or so). Please see ruclips.net/video/Cl7Yaq-G0sw/видео.html&ab_channel=LearnPiezo from time stamp 16:10 for the use of a series inductor to create a sine wave at a specified frequency
@@ultrasonicadvisors hmm I think its at the time stamp of 29:21 in this video ^, thanks for taking time to reply! can an ultrasonic transducer be driven by a square wave?
Why don't you just have dual switches and alternately switch the drive and drive-side ground flow to/from the piezo and leave out the resistor? - shouldn't that decrease your peizo time constant and be similarly simple?
That's an interesting circuit to drive a piezo disk I will be interested in the Arduino circuit so Have joined your channel "Your Link is not working" I wanted to contact you as I am involved in a project. Thanks Bob in the UK
Dr..I'm on my way to measure the highest power of my transducer at some range of frequencies. Can I still using my Class E inverter of driving circuit or..I need to construct as you mentioned here?
Its not that it isn't driving the transducer, my oscilloscope shows a signal across the transducer, and when I turn the frequency down enough I hear a high pitched wine. But I don't think its getting enough power for the effect I want. My power supply is a transformer with a 26 V RMS output attached to a high power full wave rectifier. This voltage goes to the IRF 540N power transistor through a 100 Ohm 10W resistor. I'm using my function generator for my signal source. The transducer is rated at 60W and 40 kHz, but around 39 kHz it starts to make a rattling sound. Any advice, or insight, would be greatly appreciated, thank you.
Greetings, I've been attempting to duplicate this circuit to drive ultrasonic levitation, but so far no luck. Clearly I'm missing something, so I'm reaching out to you for consultation. I'm using an IRF540N if that makes a difference.
The principle of a VNA is based on measuring the reflection coefficient. Pay attention to limitation of VNA measurement such as losses and impedance magnitude. See the graphs on the Keysight AN "Performing Impedance Analysis with the E5061B ENA Vector Network Analyzer" for more detail.
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You are a blessing.
Hi, assuming same theory also applies to humidifier peizo discs that run on 1.7mhz and 2.4mhz
Yes, but you need a high current driver for the mosfet in order to switch at that frequency.
Exactly, thanks for this crucial point
Hi, i tried the circuit and used a ESP32 board to provide 1.7mhz pwm. The peizo disc is resonant at 1.7mhz and used as humidifier/ perfume dispenser.
I can get vibrations but very weak. And within seconds the MOSFET gets damaged. I am running inductor boosted circuit at 24v and mosfet is 150v 44a capable.
sorry, don't really understand what you mean by 'successfully delivering 30kHz sine wave 20Vp-p', where do you see this?
I don't think I mentioned a sine wave in this video. Can you reference a time stamp? What the video demonstrate is a simple method to produce 20V square wave at ultrasonic frequencies (up to 100kHz or so). Please see ruclips.net/video/Cl7Yaq-G0sw/видео.html&ab_channel=LearnPiezo from time stamp 16:10 for the use of a series inductor to create a sine wave at a specified frequency
@@ultrasonicadvisors hmm I think its at the time stamp of 29:21 in this video ^, thanks for taking time to reply! can an ultrasonic transducer be driven by a square wave?
Why don't you just have dual switches and alternately switch the drive and drive-side ground flow to/from the piezo and leave out the resistor? - shouldn't that decrease your peizo time constant and be similarly simple?
You can do that, but you would need two transistors. It would definitely improve performance. I just went the extra 10 miles to keep things simple.
That's an interesting circuit to drive a piezo disk I will be interested in the Arduino circuit so Have joined your channel "Your Link is not working" I wanted to contact you as I am involved in a project. Thanks Bob in the UK
How many db was this piezo giving off. Also what was the part number
I did not measure the sound level. Search amazon for "piezo buzzer" or "piezo pickup"
Dr..I'm on my way to measure the highest power of my transducer at some range of frequencies. Can I still using my Class E inverter of driving circuit or..I need to construct as you mentioned here?
You can use your class E amp. The circuit shown here was just a demonstration.
Its not that it isn't driving the transducer, my oscilloscope shows a signal across the transducer, and when I turn the frequency down enough I hear a high pitched wine. But I don't think its getting enough power for the effect I want. My power supply is a transformer with a 26 V RMS output attached to a high power full wave rectifier. This voltage goes to the IRF 540N power transistor through a 100 Ohm 10W resistor. I'm using my function generator for my signal source. The transducer is rated at 60W and 40 kHz, but around 39 kHz it starts to make a rattling sound. Any advice, or insight, would be greatly appreciated, thank you.
i wat a ultrasoud transducer which can genrate and emit the 40khz frequency can you please suggest
Greetings, I've been attempting to duplicate this circuit to drive ultrasonic levitation, but so far no luck. Clearly I'm missing something, so I'm reaching out to you for consultation. I'm using an IRF540N if that makes a difference.
An IRF540N should work fine for this circuit depending on what you're using to drive it.
Thanks. Can we see arduino is working ?
Here I use a function generator for simplicity. Check my other videos to see how to generate a square wave from an arduino.
Great video, can you use a VNA to characterise the frequency response of your transducer?
Yes you can
The principle of a VNA is based on measuring the reflection coefficient. Pay attention to limitation of VNA measurement such as losses and impedance magnitude. See the graphs on the Keysight AN "Performing Impedance Analysis with the E5061B ENA Vector Network Analyzer" for more detail.
why DC and not AC ?
AC supplies have to be converted to a DC supply to allow for stable control of frequency.
How to make piezo louder.
@terence Drive the piezo at the resonance frequency