3-31D6 D
What is the definition of a phase-locked loop (PLL) circuit?
A. A servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator.
B. A circuit also known as a monostable multivibrator.
C. A circuit consisting of a precision push-pull amplifier with a differential input.
D. A servo loop consisting of a phase detector, a low-pass filter and voltage-controlled oscillator.
