摘要
This talk presents a 112-Gb/s four-level pulse amplitude modulation (PAM-4) extra-short-reach (XSR) transceiver (TRX) for next-generation co-packaged optics application. The RX adopts a 4-by-6 time-interleaving structure with 2b and 3b sub-ADCs for decoding the PAM-4 signal, eliminating high-speed samplers and saving significant power. The transmitter (TX) adopts the unsegmented voltage-mode driver with 3-tap feed-forward equalizer (FFE), providing high FFE resolution while consuming relatively low power. Designed and fabricated in 28-nm CMOS, the PAM-4 TRX achieve a bit error rate (BER) of < 1E-12 at 112 Gb/s with 2.16-pJ/b energy efficiency over a channel with 8.5-dB Nyquist loss.