Improved Phase Noise Performance of PFD/CP Operating in 1.5 MHz– 4.2 GHz for Phase-Locked Loop Application

Abstract

The phase frequency detector/charge pump is a significant source to raise the in-band phase noise of the phase-locked loop (PLL). The proposed CMOS-based pass transistor phase frequency detector (PT-PFD) solves the cycle skipping issue by improving the blind zone which in turn improves the phase noise performance. At the same time, in order to further improve the performance of the PLL, charge pump is integrated with the proposed design. In this case, the reset time has been reduced and thus the proposed PFD/CP functions up to the frequency of 1.5 MHz – 4.2 GHz. In addition, the modified pass transistor PFD architecture contains an advantage of less number of transistor count which consumes low power, i.e., 317.37 $\mu W$. The design is based on standard 0.18 $\mu m$ CMOS process technology with the supply voltage of 1.8 V. Moreover, the proposed design has completely eliminated the dead zone, and blind zone is minimized up to 44.23 ps which improves the phase noise to −133.8 dBc/Hz at 1 MHz offset frequency. The PFD/CP proposed herein just requires lower power consumption while producing less noise in charge pump phase-locked loop (CPLL) application.