Here, its nominal output is trimmed to 20 Vdc by components R4 and R5. The power supply circuit is a DC/DC boost converter regulator wired around the inexpensive and very popular eight-pin chip MC34063A (IC1). The prototype was successfully tested with a different 105-kHz (±5 kHz) transducer as well. Quiescent capacitor: 3,000 pF (☑5% pF).Here’s an excerpt from its machine-translated Chinese datasheet provided by the seller: I bought the 113-kHz (20-mm) transducer from one of my trusty Chinese sellers at a cost of $2 per unit. Below, you can see two oscillograms (TP2 & TP3) captured while I was running my ultrasonic mist maker prototype wired on a piece of common circuit board. So a dedicated power supply circuitry will be introduced later to fulfill that crucial requirement.īecause the circuit diagram is very simple and self-explanatory, I’m moving on to the rest of the project without giving a detailed circuit description. Even though the ultrasonic mist maker device is configured to run on a single 5-Vdc to 12-Vdc input, this transducer driver needs a 20-Vdc to 26-Vdc (V_DRIVE) power supply channel in addition to a 5-V regulated DC supply rail. In the circuit, the 5K multiturn trimpot (RP1) can be used to set the oscillator frequency to 113 kHz (±5 kHz) (TP1). As shown in the circuit diagram, it’s a tricky oscillator design based on the ubiquitous tiny time chip NE555P (IC1) to generate proper drive pulse train for the atomizer transducer.

When buying the transducer, make sure that is has a 113-kHz (☓ kHz) resonance frequency - another popular transducer has a 1.65-MHz (☐.05 MHz) resonance frequency, which is not compatible with this project! Ultrasonic mist maker circuit Transducer driver circuitīelow is the circuit diagram of the final part of the project - the transducer driver. As the liquid exits the atomizing surface of the disc, it’s broken into a fine mist of uniform micron-sized droplets, so the key component required for this little project is a particular (20-mm, 113-kHz) ultrasonic atomizer disc/transducer (see below). In an ultrasonic mist maker/humidifier (also called an ultrasonic atomizer), a piezo atomizer disc/transducer (ceramic humidifier) works by transposing high-frequency sound waves into mechanical energy that is transferred into a liquid, creating standing waves. It works fine and is, by far, the easiest ultrasonic mist maker/humidifier that I’ve ever had to get going. The following lays out my easy-to-build ultrasonic mist maker. I found lots of ideas on the internet, but they all lacked in one area or another, so I decided to design one. This is nothing just solder everything according to the circuit diagramĭont dip the piezo disc on water place the disc just above the water surface Step 6: Thanks.I needed a simple mist maker/humidifier for a project that I was working on.

Using the MOSFET we drive piezo with high voltagShould use 15 volt power supply.

Here 555 is used for genarating 113khz signal we can adjust that with 5k variable resistor.

(Watch the video for more detaild view) Step 4: Working of the Circuit If we place the piezo on top of a water surface the water will also start to vibrate.mist or fog will form due to the high vibration of water+air So if we apply 113kz signal With suitable voltage piezo disc will start to vibrate with 113kz frequency. The main component of this project is a piezo electric disc the working of the piezo is very simple.Every piezo has its own resonance frequency i n our case that is 113kz. Gather all components Step 3: The Piezoelectric Disc

Piezoelectric disc (buy piezoelectric disc from here).

Piezo disc diagram