Generative AI and machine learning are driving a demand for next-gen data centers and the need to scale up architecture for 224 Gbps-PAM4 data rates.
Overview
As generative artificial intelligence and machine learning continue to evolve, the demand for robust high-performance data centers has reached unprecedented levels of performance. To keep pace with the complex computational requirements, data centers are now compelled to scale up the system fabrics to support data transmission rates of 224 Gbps using the PAM-4 modulation scheme on every differential pair.
In May 2023, Molex announced the launch of the first-to-market chip-to-chip 224 Gbps-PAM4 portfolio to support next-gen data centers. Inception, CX2-DS and Mirror Mezz Enhanced are key solutions within the updated portfolio for the emerging hardware architectures. Let’s examine 224 Gbps-PAM4 interconnection schemes to get a clearer picture of some of their unique functions and features.
Inception Backplane and CX2-DS 224 Gbps-PAM4 for Fabrics
Molex's Inception solution is an innovative genderless backplane system that prioritizes cable connections and application flexibility. Inception’s genderless nature provides the most flexible high-speed cable design both within and between rack hardware architectures with hermaphroditic signal and mechanical integrity in the mating interface.
The communication fabric of the hardware architecture is designed for efficient communication and data exchange. The Inception cable assemblies are the physical layer signaling transport for the high-speed interconnectivity fabric. These cable assemblies form the backbone of the hardware communication architecture.
In these longer backbone connections, loss and density drive system interconnect design. Inception focuses on a mechanically robust interconnect with the lowest loss cable tailored to fit into the tightest possible volume.
To complete the fabric, the near-chip connector, CX2-DS, completes the high-speed, low-loss between the chip and surrounding components or external connection. Internal cable assemblies need to be both flexible and low loss. The CX2-DS to Inception cable assembly balances this trade-off while maintaining mechanically robust connectivity.
The components of the 224 Gbps-PAM4 family come together into a simple, fully cabled design to get the most out of the hyperscale data centers on a large scale. Combined, the components provide a means of box-to-box scale-up by interconnecting multiple chassis through 2-connector cable backplanes, 3-connector and 4-connector systems — each segment optimized for speed and tactically designed mechanical robustness.
Mirror Mezz Enhanced for Modularity
Modular hardware enables individual addition or removal of bricks thus tailoring each chassis to a desired capability level. By adding more modules to the system, the computing power of a chassis can be scaled up incrementally. When used in conjunction with the Inception/CX2 interconnection fabric, modules can be connected within a single chassis or even between separate chassis using backplane connectors and cables.
As an example, a typical mezzanine module includes an ASIC and supporting component soldered onto the board. The ASIC communicates with the mainboard through a mezzanine connector. This structure is seen in the Open Compute AI chassis.
Mirror Mezz Enhanced brings the mezzanine interconnect technology to a level capable of supporting 224 Gbps-PAM4. Impedance tolerances and crosstalk are improved relative to previous versions, while maintaining an industry leading density down to a 5mm board-to-board height. Mirror Mezz Enhanced also maintains the hermaphroditic nature of the Mirror Mezz line to reduce stock keeping unit (SKU) count on the system bill of materials (BOM).
224G Relies on Superior SI Performance and Mechanical Robustness
As a leader in the global connector market, Molex understands the value of robust connector electrical design. With higher data rates and increased signal complexity, maintaining superior signal integrity (SI) performance is imperative for 224 Gbps-PAM4 solutions. Superior SI involves minimizing signal degradation like attenuation, crosstalk, and jitter to ensure accurate transmission of high-speed data signals. Advanced SI performance helps prevent data errors, preserves the integrity of the transmitted information, and enables reliable communication between chips and components.
Along with exceptional SI performance, the system’s mechanical robustness must not be overlooked. Mechanical robustness is achieved through high-quality materials, robust connectors, secure fastening mechanisms and thermal management considerations. To support 224 Gbps-PAM4, the components and interconnects must be mechanically sound to withstand various environmental stresses, temperature fluctuations, vibration, shock, and physical handling. The connector system must address chassis-level operational environment and shipping conditions to ensure quality in final assembly.
Molex at the Forefront of 224 Gbps-PAM4 Solutions
Molex 224 Gbps-PAM4 physical layer architectures offer comprehensive solutions addressing the evolving needs of AI and hyperscale data centers. Our commitment to co-developing solutions with industry partners allows companies to customize hardware designs to fit their unique needs. With the expertise and resources to understand and execute the various elements within the 224 Gbps-PAM4 ecosystems, Molex delivers complete layer one solutions that support a wide range of channel requirements across many applications. To learn more, explore Molex’s 224 Gbps-PAM4 products.
