A novel stability analysis of a PLL for timing recovery in hard disk drives

Timing recovery in hard-disk-drive data transfer is an increasingly critica l problem due to the growing data rate to be supported. We present a novel approach to the stability analysis of a high-order digital phase-locked loo p (PLL), addressing the specific application. We find the value of the inte grating and proportional open-loop gain leading to stable behavior. The ana lysis was developed in both the digital and analog domains and the obtained results are compared. The stability analysis in the unified transforms dom ain is also developed, showing that it matches the results obtained with bo th discrete and continuous-time analysis.