Technical Blog

What is a Piezoelectric Sensor?

A Piezoelectric Sensor requires no external voltage or current source, they are able to generate an output signal from the strain applied. This makes them a popular choice for many applications. The use of them is growing significantly throughout different industries and they are sometimes incorporated into other sensors. 

“Piezo” is Greek for “press” or “squeeze” so a piezoelectric sensor effectively measures compression using the piezoelectric effect. 

A piezoelectric sensor converts physical parameters - for example, acceleration, strain or pressure into an electrical charge which can then be measured. They are highly sensitive and very small in size making them well suited to everyday objects. 

Piezo sensors are part of our product range here at Variohm; we can offer piezo cables, film elements, piezo film sheets and piezo switches. 

Characteristics of Piezoelectric Sensors

Piezoelectric sensors are strong, lightweight and constructed of flexible plastic enabling them to be available in a range of sizes, shapes and thicknesses. They will often be moulded or glued into place within applications.

Piezoelectric sensors have the following characteristics;

  • High strength
  • High voltage output
  • Elastic compliance
  • Wide frequency range 
  • Impact resistance 
  • High mechanical strength
  • High stability 

What is a Piezoelectric Sensor Used for?

Piezoelectric sensors are used in a variety of applications through different industries as they are so diverse. 

Some more commonplace applications where they are used are; 

  • PIN pads
  • Key fobs
  • Intruder/ burglar alarms
  • Microwaves
  • Alarm clocks
  • Ultrasonic equipment 
  • Musical instruments
  • Machine monitoring 

Their small size and high sensitivity make them well suited to the above applications. 

Because they are so adaptable, piezoelectric sensors are a popular choice for applications in the medical industry and they are often used for; pulse measurement - for this they can be bonded to the patient's skin and are sensitive enough to monitor the pulse. They are used in stethoscopes, and ultrasound, to measure the effectiveness of anaesthesia, for various measurements during sleep studies and within pacemakers to detect the level of movement and activity of the patient. 

Some other more industrial applications which use Piezoelectric sensors are;

  • Within accelerometers
  • Within printers to measure the impact
  • Within contact switches 
  • Non-destructive testing for various parts including parts for aerospace applications 

Piezoelectric Sensors from Variohm 

Our Piezoelectric sensors come from our supplier TE. They are available in various forms; film, cable and switches and in either standard or customised packages. 

Our Piezoelectric sensors are;

  • Flexible and light-weight
  • Have an operating temperature of -40°C to +85°C
  • High mechanical strength 
  • High impact resistance 
  • Wide frequency and dynamic range
  • Compatible for electrical to mechanical conversions 
  • Various thicknesses and sizes available

Take a look at the various piezoelectric products on our website 

For more information on piezoelectric sensors or to discuss any of the products we can offer, please contact us. 

Article published on: 24/04/2020

Article last updated on: 24/04/2020