Connectors Tackle the intricacies of Designing for 224 Gbps PAM4 Signals
SAMTEC Connectors Enable Progress in 224 Gbps PAM4 System Design
As the industry works tirelessly to reach the new paradigm of 224 Gbps PAM4 signal transmission, signal integrity and thermal challenges are at the heart of the conversation. Tackling these issues requires a fusion of cutting-edge technologies and evolved methodologies to ensure the purity of such high-data-rate signals.
At the forefront of these breakthroughs is SAMTEC, a brand synonymous with quality and innovation in the connector industry. As the topic garners attention, SAMTEC remains a pivotal contributor, deploying its expertise to develop products designed to smoothly facilitate the flow of extremely high-speed data. Frequent presence in tradeshows, with their interoperability showcases, the unveiling of new high-speed products for 224 Gbps PAM4 systems, and active participation in various educational and technical panels, confirms SAMTEC's commitment to driving the industry forward.
Integrating strategies from 112 Gbps technologies, designers are crafting solutions for the new generation of 224 Gbps systems but understand that amendments are integral to meeting the demands of signal integrity and thermal management holistically.
Although formal standards for 224 Gbps are yet to be ratified, there is already a suite of silicon and interconnects undergoing testing for the next wave of ultra-fast signal transport. A freshly published white paper delves into the distinctions between 224 Gbps PAM4 systems and their 112 Gbps predecessors regarding interconnect technologies, explores what new methodologies could pave the way for 224 Gbps PAM4 solutions, and highlights what is presently available for testing and evaluation.
BonChip Electronic proudly supplies both original manufacturer and authorized distributor resources for SAMTEC connectors, devoted to providing customers with high-quality SAMTEC connector products. With our wealth of experience and technical acumen, we are ready to offer tailored connector solutions to address your unique needs. As a trusted partner of SAMTEC, BonChip Electronic ensures you access to reliable, original factory products to meet your connectivity requirements across various domains. Contact us today at [email protected] for detailed information and superior service regarding SAMTEC connectors.
On-Package or ASIC-Adjacent Cable System
- Industry’s highest-density on-package or ASIC-adjacent cable system
- 207 differential pairs per square inch
- Eye Speed® AIR™ hyper low skew 33 AWG twinax cable
- Samtec Flyover® Cable Technology
- Designed for HDI & package substrates
OSFP 224 Gbps PAM4 Panel Assembly
- Up to 1.6 Tbps aggregate data rate
- Eye Speed® AIR™ hyper low skew 33 AWG twinax cable
- Samtec Flyover® Cable Technology
- Excellent thermal performance
- Direct attach contacts for optimized signal integrity
High-Density Mezzanine System
- Industry’s highest-density board-to-board and on-package mezzanine system
- 64 pairs in a 14 x 14 mm footprint
- Low profile design
- Up to 6.4 Tbps aggregate data rate
Extreme Performance Backplane System
- Eye Speed® AIR™ hyper low skew 33 AWG twinax cable
- 146 differential pairs per square inch
- Samtec Flyover® Cable Technology
- End 2 design flexibility
- Cable-to-cable connectivity
Challenges for 224 Gbps PAM4
At the heart of the 224 Gbps PAM4 interconnect design challenge are the issues of thermal dissipation, insertion loss, crosstalk, and skew.
As the data rate increases, the power consumption of the silicon increases. As a result, the size of the heat sinks must grow with each new generation. Solutions for 112 Gbps included low profile connectors to fit under the heat sink (optimized for footprint, not performance).
112 Gbps PAM4 designs frequently use near chip connectors (NCCs)—connectors placed next to the ASIC and connected to twinax which links to the front panel, back panel, or mid-board. This approach reduces the overall loss of the channel.
The figure above shows how Samtec Flyover® systems can improve insertion loss by routing signals via ultra-low skew twinax cable versus through lossy PCB. This Flyover approach is expected to also be well suited for many, but not all, 224 Gbps PAM4 system designs.
This graph shows insertion loss (Y axis) plotted against data rate frequency (X axis). The numerous colored lines indicate the performance of various widths of PCB traces at 1 inch of lenght, while the green line tracks an inch of Samtec Flyover system using 34 AWG twinax cable. The graph shows better insertion loss for cables vs PCBs.