250Mbps-5Gbps wide-range CDR with digital vernier phase shifting and dual mode control in 0.13

Abstract

A multi-port serial link with a wide-range CDR using digital Vernier phase shifting and dual mode control is presented. The proposed Vernier phase shifter generates fine-resolution phase steps and provides unlimited phase rotating. With the dual mode control, the proposed CDR extends the operating range from 250Mbps to 5Gbps. The proposed CDR provides 13.34ps phase steps at 5Gbps and achieves a BER of less than 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> for the range of 250Mbps to 5Gbps. Fabricated in a 0.13-μm CMOS process, the proposed CDR dissipates 19.2mW at 5Gbps from a 1.2-V supply.