A 16nm 140-fJ/b/dB Dual-Mode ENRZ/NRZ Serial Data Transceiver with Dynamic Voltage Scaling

A dual-mode long-reach serial data transceiver supporting both Non-Return to Zero (NRZ) and Ensemble NRZ (ENRZ) signaling schemes is presented. Low power dissipation, compatibility with the conventional design architectures, low sensitivity to Inter-Symbol Interference (ISI), and maintaining a high level of signal integrity are the key aspects of the proposed ENRZ link. Supporting USB and Display Port (DP) [1], [2] standards in NRZ mode, the ENRZ mode has been added as a test option to demonstrate the capability of ENRZ signaling to enhance the link throughput by 50% at the same baud-rate as NRZ, without compromising signal integrity, while enhancing energy-efficiency. Implemented in 16 nm FinFET, the proposed link covers Nyquist channel losses ranging from 6 dB up to 28 dB, with a BER better than 1 E-13 when operating at 20 Gbaud, i.e., 10 Gb/s/wire (NRZ) and 15 Gb/s/wire (ENRZ).