A new phase-locked loop system with the controllable output phase and the lock up time

Abstract

This paper, we propose a new phase-locked loop (PLL) system with controllable the output phase independent from the output frequency and lock-up time. This PLL system has a dual control loop is described, the inner loop greatly improves VCO characteristic. The main loop is the heart of this PLL, which greatly improves the output frequency instability due to the external high frequency noise coupling to the input reference frequency. This main loop has the two control inputs, the first one achieves to control the output frequency of the VCO and the other one is used to control the output phase independently from the frequency output as well as the lock-up time which can be controlled for optimum output response by this input. The experimental results confirm the validity of the proposed phase-locked loop. © 2005 SICE.