In this product demonstration from Design 2020, Keith Guetig, High-Speed Product Manager at Samtec, explains how Samtec Direct Connect™ technology enables 56 Gbps PAM4 and 112 Gbps PAM4 systems.
5G, high performance computing, emulation, AI and machine learning technology segments all benefit from bleeding edge speed and reach, especially at 56 and 112G PAM4.
Direct Connect
With Direct Connect, Samtec Flyover® cable assemblies plug directly into the chip package. This is an enabler for many other technologies. (Here’s a link that tells you more about Samtec Direct Connect)
This video shows Samtec FireFly® assemblies in Direct Connect applications, and we’ll also tell you about Si-Fly™, a new Direct Connect product that improves system density and performance even more.
In the video Keith explains the set-up of this demonstration.
Demo Design
The demonstration has eight BGA-style packages; four incorporate Samtec FireFly copper cable assemblies, and the other four use Samtec FireFly optical cable assemblies.
The signal path is from the die to the Samtec interconnect on the edge of the chip package. The Samtec FireFly assemblies plug directly into the package.
Copper FireFly assemblies incorporate Samtec 34 AWG Eye Speed® ultra-low skew twinax cable. The FireFly cable assemblies connect to Samtec Flyover QSFP-DDs.
The system in the video shows 32 of these Direct Connect assemblies routing to 16 QSFP-DD ports.
The other four BGAs are Direct Connect with Samtec optical FireFly assemblies. These terminate to 16, x 24 MTPs.
Results
Looking at one of the optical channels, connected to a Keysight scope, we see a wide open 56G PAM4 optical eye with plenty of margin for the system designer to use for the next generation system.
Advantages of Direct Connect
Compared to traditional PCB topologies, Samtec Direct Connect offers many benefits for the system architect.
First, increased density in a smaller footprint allows for higher data rate density.
Second, it’s a future proof approach. Optical and copper connectivity in the same connector provides flexibility in choosing the appropriate solution for your application.
Third, the signal channel eludes the BGA trace breakout region and offers a 5x increase in reach.
FireFly is used today, in many different industries and applications, as a mid-board connector system located adjacent to the chip package.
New Si-Fly
As mentioned previously, Samtec recently introduced Si-Fly, a new Direct Connect technology product. Si-Fly is a 112 Gbps PAM4, low-profile, high-density cable system. Si-Fly is a Direct Connect system, like FireFly.
But with Si-Fly, the contact design, extreme density, low profile, and on-package Direct Connect technology enables chip package aggregate data rate of 25.6 TB, with a path to 51.2 TB.
Using this architecture as a reference, the IEEE 802.3CK IL spec limits the reach of high speed PCB substrates to 4.5”. However, Samtec Si-Fly and ultra low skew twinax enables 22” of reach before approaching the IEEE 802.3CK IL spec limits.
Si-Fly is one of the product technologies Samtec is using toward a path to 224 Gbps PAM4 signaling.
If you have questions, please contact us at SIG@Samtec.com.
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