A 56-Gb/s Wireline Transceiver in 20nm CMOS

A feasibility of a 56-Gb/s CMOS transceiver is discussed. Simulations showed that the CMOS-inverter-based transmitter can generate 56-Gb/s signals with an inductive peaking. A receiver front- end suited for baud-rate clock recovery is demonstrated in 20-nm CMOS. Sharing the comparators for the data decision and phase detection minimizes the number of comparators in the front-end and reduces the power consumption. The front-end has a continuous-time linear equalizer followed by a 1-tap speculative decision-feedback equalizer. The front- end operates at 56Gb/s with a bit error rate of less than 10^-12 with a 0.4UI margin in the bathtub curve. It occupies 0.27mm² and consumes 177mW of power from a 0.9-V supply.