S. M.  Dartizio, Buccoleri, F., Tesolin, F., Avallone, L., Santiccioli, A., Iesurum, A., Steffan, G., Cherniak, D., Bertulessi, L., Bevilacqua, A., Samori, C., Lacaita, A. L., and Levantino, S., ?A Fractional-N Bang-Bang PLL Based on Type-II Gear Shifting and Adaptive Frequency Switching Achieving 68.6 fs-rms-Total-Integrated-Jitter and 1.56 ? s-Locking-Time?, IEEE Journal of Solid-State Circuits, pp. 1-14, 2022.