Co-Packaged Optics: Architecting the Backbone of Next-Gen Data Centers
- jenniferg17
- Oct 6
- 4 min read
Read Below:
CPO Enables 224 Gbps+ Systems: Co-Packaged Optics dramatically shortens long PCB traces, boosting signal integrity, power efficiency and thermal control for next-gen 51.2+ Tbps switches.
Si-Fly® HD Realizes CPO in Practice: Samtec’s Si-Fly® HD supports 224 Gbps PAM4 with near-ASIC connectivity and hybrid optical/electrical links in a compact footprint.
McKinsey Accelerates Adoption Regionally: As Samtec’s distributor in Africa, Türkiye and the Middle East, McKinsey Electronics offers localized support for deploying cutting-edge CPO solutions.
The New Constraints in Data Interconnects
In hyperscale data centers, the pressure to deliver exponentially more bandwidth per watt is relentless. Yet, traditional PCB-based electrical interconnects are constrained by physical realities: increasing losses, crosstalk, EMI and growing power consumption due to complex signal conditioning at higher speeds.
The transition from 112 Gbps PAM4 to 224 Gbps PAM4 and beyond has pushed copper traces and traditional connectors to their limit. What once worked with relative simplicity now demands elaborate equalization, power-hungry retimers and aggressive thermal management, none of which scale economically or efficiently at the rack or even at the board level.
The Case for Co-Packaged Optics
Co-Packaged Optics is not merely a component evolution; however, it represents a topological shift in system design. Instead of routing high-speed signals from the switch ASIC across long PCB traces to optical pluggables on the front panel, CPO locates the optics immediately adjacent to the ASIC itself. This proximity reduces the length of lossy electrical interconnects, enabling higher data rates and dramatically lower power per bit.
Critically, by integrating optics and switching silicon within the same package or substrate, designers can reduce or eliminate the need for multiple retimers and simplify trace impedance tuning. Assuming that thermal and mechanical challenges are properly addressed, this improves link margin and reduces BOM cost.
The industry now sees CPO as a necessity for 51.2 Tbps and 102.4 Tbps class switches.
Technical Dimensions of CPO Integration
Deploying co-packaged optics introduces a set of tightly coupled technical considerations that must be solved collaboratively by packaging engineers, optical designers and system architects:
Signal Integrity and Bandwidth
Short electrical traces between ASIC and optical engines minimize insertion loss and reflections, enabling clean 224 Gbps PAM4 signaling. This is a quantum leap from legacy 56 Gbps NRZ and requires precision-engineered substrates with tightly controlled impedance and ultra-low skew.
Power Efficiency
CPO eliminates intermediary SerDes and drivers, shaving off milliwatts per gigabit that would otherwise accumulate across hundreds of I/O lanes. This energy efficiency is not trivial; at hyperscale, it translates into megawatts saved across data centers.
Thermal Management
Integrating laser drivers and photodiodes alongside high-power ASICs requires novel cooling strategies. Co-thermal design zones, microchannel heatsinks, and even liquid cooling are under active exploration to maintain junction temperatures within spec.
Manufacturability and Reliability
Aligning fiber arrays or high-speed cable assemblies with micron precision, maintaining long-term optical performance under thermal cycling and ensuring reworkability are all deemed non-trivial challenges. The supply chain for CPO must mature rapidly to provide high yield and serviceability.
Si-Fly® HD: A Realization of CPO Principles by Samtec
Samtec’s Si-Fly® HD product is one of the most technically advanced demonstrations of near-chip optical and electrical interconnect. Instead of a rigid PCB trace, it uses an ultra-low-loss twinax or optical cable that terminates at the ASIC package, thus dramatically reducing the signal path length and its associated losses.
Key Features:
Supports 224 Gbps PAM4 signaling per channel, enabling next-gen switch and compute ASICs.
Near-ASIC Connectivity: With less than 7mm electrical path from silicon to cable, signal integrity is optimized even at extreme data rates.
High-Density Footprint: Fits within a 95mm x 95mm co-packaged substrate, allowing dense system-level integration.
Hybrid I/O Support: Works with both electrical and optical links, providing flexible deployment options depending on rack topology.
The Si-Fly® HD is an ecosystem enabler. By solving the physical interface between silicon and optics in such a compact form, it allows system designers to shift the optical/electrical boundary closer to the chip, simplifying the front panel and enhancing thermal locality.
Market Momentum and Industry Shifts
The data center optics industry is aligning rapidly around CPO:
According to a 2025 GlobeNewswire report, the CPO market is expected to grow from $2.43 billion in 2025 to $4.67 billion in 2030, a CAGR of 13.74%.
Companies like AMD are acquiring photonic design houses (e.g., Enosemi, 2025) to accelerate their CPO integration roadmap.
The Open Compute Project (OCP) is standardizing interfaces and management frameworks for interoperable CPO modules, laying the groundwork for vendor-agnostic deployments.
This convergence signals that co-packaged optics will not remain a niche high-end option but will become a mainstream interconnect technology in hyperscale and enterprise environments.
Engineering the Future of I/O
As we cross into the 224 Gbps era and beyond, the foundations of data center design are being rethought. Traditional signal routing over PCBs is ceding ground to integrated photonics and near-chip cabling. Co-Packaged Optics stands at the core of this transformation.
Samtec’s Si-Fly® HD is a tangible expression of this future, offering real-world performance, manufacturability and system-level value that helps transition from concept to deployment. For engineers architecting the next wave of networking, compute and AI infrastructure, CPO is a roadmap imperative.
As an authorized distributor of Samtec across Africa, Türkiye and the Middle East, McKinsey Electronics is playing a vital role in accelerating the adoption of transformative interconnect technologies like Si-Fly® HD. Headquartered in Dubai, with regional offices in South Africa, Türkiye and Tunisia, McKinsey Electronics bridges the gap between advanced system design and real-world deployment. By offering localized support, technical consultancy and reliable access to cutting-edge solutions such as Samtec’s co-packaged optics platforms, McKinsey empowers data center architects, AI system designers and high-performance computing engineers in the region to stay ahead in the 224 Gbps era.
Sources
Samtec Si-Fly® HD: https://www.samtec.com/products/sfcc
CPO Market Report 2025: https://www.globenewswire.com/...
AMD Acquisition of Enosemi: https://www.reuters.com/...
Mouser on Samtec CPO Products: https://www.mouser.com/...
OCP CPO Standards: https://www.opencompute.org/projects/optical-interconnect
