资料介绍
pll 设计快速入门ECE 6414 - Multipliers and PLLs (12/23/01)
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PHASE-LOCKED LOOPS Components of a Phase-Locked Loop Function of a phase-locked loop is to lock the frequency of a VCO to an input frequency. Block diagram:
Input fin Frequency Phase Frequency Detector (PFD) fosc VCO
MPLL09
LPF
Vo Output Voltage
Components: Phase/frequency detector outputs a signal that is proportional to the difference between the frequency/phase of two input periodic signals. The low-pass filter is use to reduce the phase noise and enhance the spectral purity of the output. The voltage-controlled oscillator takes the filtered output of the PFD and generates an output frequency which is controlled by the applied voltage.
ECE 6414 - Multipliers and PLLs (12/23/01)
Page 28
Phase/Frequency Detectors Types: Analo
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