Ethernet transceiver module BCM85821

The Broadcom® BCM85821 is the industry’s highest-performance and lowest-power 800GbE PAM-4 PHY transceiver capable of driving four lanes of 226-Gb/s PAM-4 at 113 Gbaud, while supporting 400G DR1.2 and 1.6T DR4.2. The BCM85821 leverages the market-leading 5-nm PAM-4 PHY transceiver technology platform, already proven with the BCM85812, and provides a path to accelerating 1.6T OSFP-XD optical module availability. The advanced Broadcom DSP technology and equalization techniques compensate for optical impairments while maintaining the world’s lowestpower pluggable optical modules and co-packaged optical solutions to enable the deployment of 51.2-Tb/s and higher-density switch ASICs. The BCM85821 incorporates a highly differentiated feature set, including market-leading FEC capability options and client-side switch ASIC SerDes interoperability, to provide an unmatched competitive advantage to the market. In 800GbE mode, the BCM85821 converts eight lanes of 106 Gb/s from the client side into four lanes of 226 Gb/s to drive next-generation high-density optical PAM-4 links inside OSFP-XD form-factor modules. The BCM85821 also features crossbar on the client side for easier routing in the PCBs. The on-chip clock synthesis is performed by a low-cost 312.5- MHz or 625-MHz reference clock through high-frequency, lowjitter phaselocked loops Features Single-chip 4 × 200G PAM-4 PHY drives 800GbE over optics: Client side: 8 × 106G PAM-4 Line side: 4 × 226G PAM-4 (128,120 inner code with 2-bit padding) Supports forward gearbox for backward compatibility with 400G optical modules