A 16nm 140-fJ/b/dB Dual-Mode ENRZ/NRZ Serial Data Transceiver with Dynamic Voltage Scaling
Armin Tajalli, Cosimo Aprile, Milad Ataei, Rolf Beerwerth, Dario Carneli, Maik Fuhs, Kiarash Gharibdoust, Ali Hormati, James Hudner, Victor Perrin, Amin Shokrollahi, Richard Simpson, Andrew Stewart, David Stauffer, Giuseppe Surace, Roger Ulrich, Patrick Urban, Mark Venneborger, Anant Singh · 2025
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).