Yen-Long Lee Soon-Jyh Chang Yen-Chi Chen Yu-Po Cheng An Unbounded Frequency Detection Mechanism for Continuous-Rate CDR Circuits. 500-504 2017 64-II IEEE Trans. Circuits Syst. II Express Briefs 5 https://doi.org/10.1109/TCSII.2016.2584106 db/journals/tcas/tcasII64.html#LeeCCC17