With the rapid development and growth of AI, cloud, and high-performance computing, the demand for computing and switching capacity in data centers is growing exponentially. This has led to several technical constraints and challenges, such as increases in power consumption, bandwidth, latency, and reliability. One of the upcoming solutions to fulfill these requirements is Co-Packaged Optics (CPO), where the Optical Engine (O/E) is positioned close to the switch chip (ASIC). This reduces the length of the electrical circuits on the printed circuit board (PCB), which in turn reduces power consumption, latency, and signaling crosstalk. This close integration also allows channels to reach 100 Gb, 200 Gb, and potentially 400 Gb speeds at very high densities. According to Yole, the global CPO market will reach $2.6 billion by 2033, and the explosion of AI computing power is accelerating the mass production penetration of this technology.

Because the O/E is so closely integrated with the ASIC, the optical signal needs to be routed to the front-plate of the switch, which presents its own challenges. First, we’re dealing with a high density of fibers, up to 1024 fibers per ASIC for data traffic. Then, there’s the restricted space within the switch, where fibers must share space with the PSU, cooling systems (such as ventilators and, if applicable, liquid cooling), the data plane (ASIC), O/E, control plane (CPU), management interface, and connectors. Finally, there’s the need for connectivity over Polarization-Maintaining Fiber (PMF) for the External Laser Source (ELS). These have been separated from the O/E to provide better stability and serviceability. This means all these cables need to be neatly dressed and tightly routed (i.e., with a small bending radius) within the confined space of the switch.

Why the Need for a CPO Interconnect Shuffle?

The grouping of fiber channels on the O/E differs from standard MPO or LCD connectors and needs to be re-organized between leaving the O/E and reaching the front-plate connectors. We also have a mixture of connectivity, where data signals leave the O/E, but the ELS PMF feeds the O/E with stable laser light. By ensuring the cables are segregated per engine allows each O/E to be separately serviceable, thus improving the reliability of the switch. The Shuffle can route 200 µm, 250 µm, 600 µm, or 900 µm fibers with a precision of <0.1 mm in complex patterns and bends, in a reliable and repeatable way, to ensure every connection delivers maximum performance.

What are the Main Features of the CPO Interconnect Shuffle?

1. Controlled and Automated Cable Management:With AI-automated fiber mapping and routing, the impact of micro- and macro-bending can be significantly reduced, improving Insertion Loss (IL) and Return Loss (RL) optical characteristics. The routing can be managed so that different fiber paths are within 1.0 cm of each other, promoting similar optical output signals. Additionally, the Shuffle can be repeatedly produced in the same way, ensuring these characteristics are consistent across every Shuffle, leading to predictable and high-quality optical performance.
2. High Density and Complex Routing:With routing accuracy of better than 0.1 mm, fibers can be routed very close together on a flex substrate, allowing it to be less than 1 mm in height. This enables the installation of several layers of high-density fiber mapping, maximizing port count in minimal space. Here too, AI can be used to ensure even the most complex routing scenario is guided correctly, Shuffle after Shuffle.
3. Installation and Serviceability:Using a Shuffle in a modular cassette allows you to connect with each O/E separately yet maintain the same length for the different fanouts, even if each link has different routing and overlength. The low height of the Shuffle permits storing the different excess lengths of each fanout in the cassette. This segregation helps to keep individual O/Es separately serviceable, facilitates an easier installation process, and simplifies stock management, ultimately reducing downtime and operational costs. Using unified CPO Interconnect Shuffles will also allow for setting consistent target values for IL and RL in factory-assembled and tested Shuffles, thereby improving quality control.

ADTEK’s Shuffle Solution

As a leading provider of optical connectivity solutions, ADTEK closely follows market trends and officially launches its high-density optical fiber management solution based on polyimide flexible board. The ADTEK CPO Interconnect Shuffle is an innovative solution for confined spaces with integrated connectivity on flame-retardant substrates.

1. Flexible Film Structure:The flexible film substrate design supports any custom optical fiber routing line, which can accurately meet the needs of high-density wiring. It is pre-terminated, factory-tested, and ready to be installed, thereby significantly reducing deployment time and on-site labor.
2. Customization:The optical fiber link route and the number of optical fibers can be flexibly adjusted according to the actual needs of users. Full customization services—from routing design to substrate cutting, including substrate size, shape, optical fiber mapping, connector types, and positioning—can be provided to ensure a perfect match between the solution and the packaging module, guaranteeing optimal system integration.
3. Efficient Mass Production:Relying on mature precision manufacturing and automated fiber distribution technology, it supports large-scale and high-consistency product delivery to meet the timeliness and quality requirements of large-scale deployment, ensuring reliable supply for demanding projects.
4. Stacked Multi-Layer Design:Our stacked multi-layer design, a flexible backplane, can achieve thousands of optical fiber cross- and interconnections, optimize space, and enhance airflow in dense equipment. It offers the advantages of simplifying optical fiber wiring management and flexible anti-vibration, making it especially suitable for high-density scenarios inside CPO switches and equipment that needs to handle hundreds to thousands of optical fibers.
5. Versatility:Supports LC, MT, MMC, MDC, MPO, SN, SN-MT, and other connectors, adaptable to diversified applications. Users do not need to manually jumper or route fibers; they only need to pay attention to the uplink and downlink interfaces, making it a plug-and-play solution that improves installation efficiency and reduces operation and maintenance costs.
6. Low Loss and High Reliability:It reduces system complexity and connection loss, and improves signal transmission efficiency. At the same time, it has undergone strict mechanical integrity and environmental durability tests to ensure high product reliability and long-term performance in demanding environments.

With the continuous explosion of AI computing power and the acceleration of data center high-density processes, the transmission rate of Serdes has increased, and the iteration of CPO technology is accelerating. The popularization of CPO technology is not only an inevitable choice for the computing revolution but will also reshape the optical interconnection architecture of data centers. ADTEK will continue to deepen its expertise in CPO optical fiber interconnection, with the Shuffle flexible optical circuit board as its core, to provide global customers with highly adaptable and reliable solutions and help build a more efficient, more reliable, and greener next-generation optical interconnection network.