Development of Frequency-Fixed All-Pass Filter-Based Single-Phase Phase-Locked Loop

A Frequency Synthesis of All Digital Phase Locked Loop

All Digital Phase locked loops (ADPLL) plays a major role in System on Chips (SoC). Many EDA tools are used to design such complicated ADPLLs. It operates on two modes such as frequency acquisition mode and phase acquisition mode. Frequency acquisition mode is faster compared to Phase acquisition, hence frequency synthesis is performed. The CMOS technology is used to design such a complex desig...

High Speed Delay-Locked Loop for Multiple Clock Phase Generation

In this paper, a high speed delay-locked loop (DLL) architecture ispresented which can be employed in high frequency applications. In order to design the new architecture, a new mixed structure is presented for phase detector (PD) and charge pump (CP) which canbe triggered by double edges of the input signals. In addition, the blind zone is removed due to the elimination of reset signal. Theref...

Single Phase Variable Sampling Phase Locked Loop using Composite Observer

An observer based variable sampling period phase locked loop is introduced for grid connected systems. The composite observer acts as an efficient estimator of the fundamental components from a periodic input signal rich in DC and harmonics. The observer gains are designed using pole placement technique, which inherently ensures the stability of this estimator. Even under drift frequency, a con...

Grid-voltage Synchronization Algorithms Based on Phase-locked Loop and Frequency-locked Loop for Power Converters

Phase Locked Loop Circuits

1. Definition. A PLL is a feedback system that includes a VCO, phase detector, and low pass filter within its loop. Its purpose is to force the VCO to replicate and track the frequency and phase at the input when in lock. The PLL is a control system allowing one oscillator to track with another. It is possible to have a phase offset between input and output, but when locked, the frequencies mus...