fáziszároló

A fáziszároló, or phase-locked loop (PLL), is a control system that generates an output signal whose phase is related to the phase of an input "reference" signal. It is an electronic circuit consisting of a phase detector, a low-pass filter, and a voltage-controlled oscillator (VCO). The phase detector compares the phase of the input signal with the phase of the output signal from the VCO. If there is a phase difference, the detector generates an error signal. This error signal is then filtered by the low-pass filter, which smooths out rapid fluctuations. The filtered error signal is used to control the VCO, adjusting its frequency and phase until it matches the input signal.

PLLs are used in a wide variety of applications. In telecommunications, they are employed for frequency synthesis, demodulation of FM and PM signals, and clock recovery from digital data streams. In consumer electronics, PLLs are found in radios and televisions for tuning to specific frequencies, and in audio equipment for precise clock generation. They are also utilized in motor control systems, where they can be used to synchronize motor speed to an external reference. The core principle of a PLL is its ability to lock onto and track the phase of an incoming signal, making it a fundamental building block in many electronic systems requiring precise frequency and timing control.