A 3.5/7.0/14-Gb/s multi-rate clock and data recovery circuit with a multi-mode rotational binary phase detector

A new type of multi-rate clock and data recovery (CDR) circuit is realized that can operate at multiple data rates of 3.5, 7.0 and 14-Gb/s. A multi-mode rotational binary phase detector supports full-rate, half-rate and quarter-rate CDR operation with only one voltage-controlled oscillator. A prototype CDR circuit implemented in 65nm CMOS technology successfully demonstrates the multi-rate operation with energy efficiency of 0.64pJ/bit and chip size of 0.017mm2, both of which are much less than those of conventional multi-rate CDR circuits.