All change for pluggable optics – report

News and Business

The composition of pluggable optics is changing, according to LightCounting’s nineth edition of its Silicon Photonics report which includes a new market forecast for linear drive pluggable and co-packaged optics. LightCounting says it expects that market share of transceivers using SiP-based optical modulators will increase from 24% in 2022 to 44% by 2028.

It also notes that modulators based on other thin film materials can be manufactured on silicon wafers and combined with a wide range of optical elements and electronic ICs, using SiP as the integration platform. These materials currently include Thin Film Lithium Niobate (TFLN), Barium Titanate (BTO) and electro-optics polymers, which the report combines into a “TFLN and other” category in the figure below.

Another highlighted transition in the industry is the adoption of linear drive pluggable (LPO) transceivers and co-packaged optics (CPO). The report notes that both solutions offer significant reductions in power consumption in comparison with standard re-timed transceivers with PAM4 DSP chips inside them. Removing the DSPs saves power, but more complex SerDes are needed to make direct drive possible.

Broadcom’s 100G SerDes were developed with CPO in mind, but LightCounting says it seems to support LPO as well. Early results for 800G LPO modules driven by 100G SerDes are very encouraging. It is very unlikely that LPO will work with 200G SerDes, however, so CPO may be the only option for 1.6T ports.

LightCounting concludes that not all LPO and CPO solutions will be based on SiP technology, but SiP is the current front runner and the ideal integration platform for new materials as well. It says SiP modulators are currently the best option for linear drive designs, since GaAs directly modulated lasers (DMLs) and InP electro-absorption modulated lasers (EMLs) are more “non-linear” devices. That said, the report says it is safe to predict that all LPO/CPO devices, except for VCSELs, will be based on a SiP platform. All the new materials (TFLN, BTO and polymers) will use a SiP platform for integration with other optical elements and electronics.

The report also presents a new forecast for LPO and CPO sorted by reach and data rate. It says conventional re-timed pluggables will continue to dominate the market for the next five years, and probably longer than that. However, LPO/CPO ports will account for more than 30% of the total 800G and 1.6T ports deployed in 2026-2028. As usual, nothing may happen for a while until suddenly this change is here for all of us to see.

For more information, visit www.lightcounting.com