Definition and Functionality of Piezo Switch
– Electrical switch based on the piezoelectric effect
– Generates electric charge when materials are under stress
– Charge used to turn on an integrated semiconductor device
– Output of switch assembly becomes active when device is on
– Current flows through the device when it is on
Operation of Piezo Switch
– Voltage pulse dissipates in the gate resistor
– Field effect transistor (FET) turns off after the pulse
– FET returns to its normal high impedance state
– Piezo element bends slightly under compressive pressure
– Piezo switch produces a single, brief on pulse
Advantages of Piezo Switch
– No moving parts, ensuring long lifetime
– Tens of millions of operations without wear
– Can be completely sealed from the environment
– Weatherproof construction with stainless steel housings
– Resistant to damage by vandals or heavy use
Adjusting the Pulse Width of Piezo Switch
– Higher pressures generate higher voltages and longer pulse width
– Capacitor can store charge to lengthen time constant
– Additional circuitry can extend the pulse width further
– Pulse width can be used to change the state of an output
– Flip-flop can be toggled using the pulse width
Applications of Piezo Switch
– Consumer electronics such as mobile phones and tablets
– Industrial control systems and automation
– Medical devices and equipment
– Automotive industry for various switches and controls
– Aerospace industry for switches in aircraft and spacecraft.Sources: https://en.wikipedia.org/wiki/Piezo_switch
