Quartz crystals are used in circuits where a very accurate and constant frequency is required, e.g. in most transmitters, in clocks, microcontrollers, cell phones, computers as well as in frequency counters and digital signal generators.
A quartz crystal alone determines only the frequency. Since a quartz crystal in itself is neither an oscillator nor a clock generator, it must be operated in an appropriate circuit to represent a crystal-stabilized oscillator circuit (crystal oscillator).
A quartz crystal is based on an artificial quartz crystal and serves as an electronic component for oscillator circuits, generating electrical oscillations with a defined frequency. Its operation is based on the principle of electromechanical resonance of the installed piezo-electric and quartz crystal contacted with electrodes.
Due to the piezo-electric properties of quartz, it performs precisely defined oscillations (resonance) under the influence of alternating electrical voltages. Electrically, the quartz then behaves like an oscillating circuit with high Q and thus acts as a clock generator in many applications with the appropriate circuitry.