2024, Vol. 5, Issue 2, Part A

This study presents the design and performance analysis of a high-speed Phase Frequency Detector (PFD) using D flip-flops with reset terminals in 45nm CMOS technology. The objective was to address common limitations in traditional PFD designs, such as increased jitter, phase noise, and power consumption, while ensuring robust performance across varying frequency ranges. The proposed architecture leverages the inherent synchronization and reset capabilities of D flip-flops to minimize dead zones, improve phase detection accuracy, and reduce propagation delays. The design was implemented and simulated using the Cadence Virtuoso and Synopsys HSPICE tools, with key performance metrics—power consumption, jitter, phase noise, and duty cycle—analyzed across a frequency range from 100 MHz to 1000 MHz.

The results demonstrated a gradual increase in power consumption from 2.1 mW at 100 MHz to 6.0 mW at 1000 MHz, highlighting the impact of increased switching activity at higher frequencies. Jitter values remained stable at lower frequencies but increased from 3.2 ps to 7.2 ps as frequency rose, primarily due to metastability and timing mismatches. Phase noise performance degraded from -80 dBc/Hz at 100 MHz to -58 dBc/Hz at 1000 MHz, indicating the expected noise coupling effects at higher frequencies. However, the duty cycle remained stable, with minimal deviations from the ideal 50% mark across the frequency range.

These findings indicate that the proposed design outperforms conventional PFD architectures in terms of power efficiency, jitter control, phase noise management, and duty cycle stability. Practical recommendations emphasize optimizing transistor sizing, implementing adaptive reset techniques, and exploring hybrid analog-digital feedback systems for further improvements. This research contributes significantly to the development of reliable, high-performance PFDs for applications in clock synchronization, frequency synthesizers, and high-speed digital systems.