How to find the right Piezo Transducers AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Piezo Transducers
- Transducer vs indicator (buzzer)
- An externally driven piezo transducer needs an AC or square-wave drive signal. A piezo indicator or buzzer has a built-in oscillator and just needs DC. Buying the wrong type means silence on DC or no frequency control on an indicator.
- Resonant frequency
- Drive at or near the rated resonant frequency for maximum output. Output drops sharply away from resonance.
- Rated drive voltage
- Stay within the rated drive voltage, and compare sound output at the same distance and voltage across datasheets. Datasheets measure sound output under different conditions, so comparisons are only valid at matched conditions.
- Housed vs bare element
- Bare piezo discs need an enclosure or proper nodal mounting. Housed units come acoustically tuned. Clamping a bare disc at the wrong point kills its output.
- Sensing vs sounding
- For vibration, knock or force sensing, use elements or film sensors specified as sensors, with suitable input protection on the receiving circuit. Piezo elements can generate high voltage spikes when struck.
- Mounting and environment
- Choose PCB, wire-lead or panel mount to suit the build, and check sealing for washdown or outdoor use. Unsealed buzzers fail quickly in wet or dusty environments.
Brands that matter
- Murata: Piezo sounders, buzzers and elements for electronics.
- TDK: Piezo buzzers, sounders and actuators.
- CUI Devices: Range of piezo transducers and buzzers with clear datasheets.
- PUI Audio: Audio components including piezo transducers and indicators.
- TE Connectivity: Piezo film sensors for vibration and impact sensing.
What to avoid
- Buying a self-driven buzzer when you need to play different tones.
- Driving a piezo element directly from a microcontroller pin without considering its capacitance and needed drive level.
- Using a piezo sensor without protecting the input it feeds.
Questions
Why does my piezo make no sound on a DC supply?
It is an externally driven transducer. It needs an oscillating drive signal, so either drive it with a square wave or buy an indicator type with a built-in oscillator.