A 0.14-to-0.29-pJ/bit 14-GBaud/s Trimodal (NRZ/PAM-4/PAM-8) Half-Rate Bang-Bang Clock and Data Recovery Circuit (BBCDR) in 28-nm CMOS. - Zhao, Xiaoteng; Chen, Yong; Mak, Pui-In; Martins, Rui Paulo (2019)