At OCP Summit 2022, we managed to see some new technology in the co-packaged optics space. The Open Compute Foundation is primarily driven by hyper-scaler spend. As a result, many leading-edge technologies are shown at the annual OCP Summits. This year was no exception with the Broadcom co-packaged optics and silicon photonics demos at the Ragile Networks booth.
Awesome Broadcom Co-Packaged Optics and Silicon Photonics OCP Summit 2022
The first demo was showing 3.2Tbps optics demos. Here we can see the 400Gbase-FR4 modules neatly organized around the edges of the Broadcom NPO/ CPO switch.
Having optics packaged this near to the switch ASIC actually is unlikely to be the longer-term fix for the industry. They do not offer anywhere near the power consumption savings of co-packaged optics since there are external lasers and the distances over copper are further. Still, it was interesting to see the NPO switch, especially since four of the 400Gbase-FR4 modules were Intel-branded.
Then came the “big show”. We saw this placard and the chip next to it was the Broadcom SCIP CPO chip.
What you are looking at is a Broadcom switch chip with four pluggable modules along two edges of the chip to provide optical I/O.
Here is a top-down view:
Giving some sense of what is underneath that lid, Broadcom’s engineers had to co-package silicon photonics and get alignment between both the switch ASIC and the electrical to optical chip. The four connectors on each side offer the fiber density of five MPO-12 connectors, but in a smaller form factor.
It is difficult not to draw parallels to this Intel Silicon Photonics Connector. Intel’s solution appears to be a bit different with the connector plugging into the package, but it was very cool to see from Broadcom. Here is the video on that one and with more from Intel Innovation a few weeks ago.
Final Words
We have been talking about co-packaged optics for a long time now. Indeed, we even did a piece on it back in 2019 in Hands-on with the Intel Co-Packaged Optics and Silicon Photonics Switch. We have also covered the topics at various OCP Summits and other events.
Still, the key is clearly that this is coming. We are going to see more of it, especially in the 51.2Tbps era. We will have a piece soon on the 64x 800GbE Broadcom Tomahawk 5 51.2Tbps Switch Chip running at the show. That is where we expect to see more CPO with more switches transitioning when we hit the 1.6Tbps Ethernet switch generation around two years later (based on the current cadence.)
Can’t wait for this to get miniaturised to a point where we have CXL on PCIe on USB5 with optical cables for data twisted with copper for power. Those will be cool looking spiral cables, and less attractive to our cats, lol.
Fantastic!
Very cool chip. Now, if only Broadcom would let you photograph the ball array on the bottom of the package so we can see how many pins the thing requires to connect to the motherboard.