An 800GbE PAM-4 PHY Transceiver that Supports 42dB Copper and Direct-Drive Optical Applications in 7nm

Low-power high-speed transceivers are critical for data-centers and supercomputers to host the rapid growing artificial intelligent applications. Recently, the market demand for 800G transceivers surges thanks to its ability to support higher rate and lower latency data transmission [5] [6] [20] [23]. However, aggressive power budget imposed by optical module's tight thermal constraint and data center's operating cost poses great challenges for the transceiver design. This work presents a low power DSP-based single-chip 800GbE PAM-4 PHY transceiver in 7nm FinFET technology capable of driving eight lanes of up to 112.5Gb/s. It supports both electrical and optical links with monolithic integrated laser driver enabling direct-drive PAM-4 output capability for EML and silicon photonics. Thanks to both architecture level and circuit level innovations, this work achieves pre-FEC BER<3E-8 under 42dB channel with 2.59pJ/b analog power efficiency, which is the best power-efficiency among the published 112Gb/s and 224Gb/s transceivers. The integration of high-swing driver enables significant power savings against the conventional stand-alone laser driver solutions.