Contents
What is PLL design?
A phase-locked loop or phase lock loop (PLL) is a control system that generates an output signal whose phase is related to the phase of an input signal. There are several different types; the simplest is an electronic circuit consisting of a variable frequency oscillator and a phase detector in a feedback loop.
What is the PLL basics?
The basic blocks of the PLL are the Error Detector (composed of a phase frequency detector and a charge pump), Loop Filter, VCO, and a Feedback Divider.
What is bandwidth of a PLL?
Bandwidth is approximately the unity gain point for open loop PLL response. The bandwidth setting allows you to control the bandwidth over a finite range to customize the PLL characteristics for a particular application. The Quartus II software provides four bandwidth settings — low, medium, high, and auto.
What are the basic requirements of a PLL?
The major basic requirements in the design of a PLL frequency synthesizer are to achieve the performance goals of low phase noise, low spurious output and to step, or hop, from one frequency to another in a specified amount of time.
What should be the capacitance of a PLL?
First, it’s important to match the impedance at the reference input port of the PLL to minimize reflections. Also, keep the capacitance in parallel with the input port small, as it will decrease the slew rate of the incoming signal and add noise to the PLL loop.
How to design and debug a phase locked loop ( PLL ) circuit?
Designing and debugging a phase-locked loop (PLL) circuit can be complicated, unless engineers have a deep understanding of PLL theory and a logical development process. This article presents a simplified methodology for PLL design and provides an effective and logical way to debug difficult PLL problems. Simulation
How to choose a reference frequency for a PLL circuit?
Many engineers are confused as to how to choose a reference frequency, but the relationship between the reference frequency and the output frequency step is simple.