An 8 - 26 Gb/s Single Loop Reference-less CDR with Unrestricted Frequency Acquisition

초록

This paper presents an 8?26 Gb/s single loop referenceless CDR with unrestricted frequency acquisition. The CDR circuit is designed in a 28 nm CMOS technology. A frequency detector (FD) controller and mode switch are proposed to extend the frequency capture range of the frequency detector. The phase frequency detector (PFD) with the FD controller and the mode switch has unlimited capture range as long as the target frequency is within the frequency range of the VCO. The simulation shows the proposed CDR achieves the capture range from 8 Gb/s to 26 Gb/s and the frequency acquisition time of 0.47μs.