Piezo keypads

In 2011, Unipad company completed the stage of development and operational testing of a completely new type of keypads based on the piezo technology and launched their commercial Products. By now, a number of standard keypads and single non-contact switches (buttons) have been developed. The algorithm of designing specialized keypads according to customer's specifications has been perfected.

Modern requirements for energy efficiency, reliability, miniaturization, adaptability to computer management and control systems, force more and more manufacturers of machinery and equipment to start searching for new technological solutions for Products of switching products. Piezoelectric elements turned out to work well when used as electromechanical transducers. Their application in electrical signal switching products led to a qualitatively new level of Products of buttons, keypads, switches and integrated products on this basis.

A piezoelectric keypad is a set of piezoelectric switches (piezo buttons) which make up a single panel and are connected into a common electrical circuit. The principle of work of piezo buttons is based on the direct piezoelectric effect. Pressing with a finger on the tactile surface of a piezo button causes deformation of the piezoelectric element mounted under the outer surface and results in a voltage appearing on its electrodes, which is sufficient to control non-contact transistor keys. High sensitivity of piezoelectric elements to deformation and the absence of moving contacts allow producing keypads in metal housing, which results in high values of electromagnetic compatibility, ingress protection, vandal resistance and reliability.

The main technical characteristics of piezo keypads.

Switching voltage, V   Up to 300
Alternating current/direct current, A Up to 2
Closed electrical contact resistance, Ohm <5
Open electrical contact resistance at standard conditions, MOhm > 5
Key lifecycle > 50 million
Operating temperature range,  °С - 60° to + 100°С
Standard pressing force 3-5N
Possible range of pressing force 0,5-15 N
Electrical safety The products belong to the category of electrical devices which use safe extra-low voltage, have no moving or hot parts and hence, a contact closure is not accompanied by sparks or arcing.
Explosion safety Dielectric nature of piezo elements, its functioning under the action of an electric field, lack of electric power and associated heat generation in the range of infra-low frequency (current leakage at 10-8А) make piezo elements intrinsically safe.
Shock resistance 100g  1-5 ms 
Vibration resistance The products are resistant to vibration loads in the frequency range from 0.5 to 200 Hz with a maximum acceleration of 2g and impact resistant with a maximum acceleration of 3g. 
Dust and waterproof IP 68

Contactless piezo products (piezo buttons, piezo keypads) do not require any additional power supply (similarly to mechanical buttons) and are designed for switching of electric circuits of AC and DC.

Distinctive features of these products:

  • high reliability (50 million operating cycles);
  • ability to work in corrosive environments, water, sand, metal chips;
  • explosion safety;
  • wide operating temperature range (from -60 to +100°C);
  • wide range of switched currents and voltages;
  • electromagnetic compatibility;
  • optional vandal-resistant design

allow their use in equipment designed to operate in harsh environments, in the petrochemical industry, in mines or on special machinery.

Currently we are preparing the detailed information about piezo keypads in PDF. In case of any questions, please feel free to contact us.