Electronic device designers have a need for higher speeds, and they can use new specifications that enable them. For example, the September 2014 specifications for CDFP 2.0 interoperable hot pluggable interconnect modules enable data rates of 25 Gbps over 16 lanes, for an aggregate data transmission speed of 400 Gbps.

However, Molex exceeded that when demonstrating an assembly that used existing technology, including ICs from Avago Technologies, CDFP connectors from Molex, and a one-meter passive cable. While designed for 25 Gbps per lane, the assembly ran at 32 Gbps per lane and 512 Gbps in aggregate.

Speed can be increased by simply increasing NRZ (non-return-to-zero) data rates through very-high-speed serial interconnects, though this requires different connectors. Another way to “turbocharge” a 25 Gbps connection is to update the IC and encode data using PAM4 (pulse amplitude modulation), which makes it theoretically possible to reach 800 Gbps in aggregate.

While PAM4 is more complex than binary NRZ, it is much faster. NRZ uses PAM2, which has just two data encoding levels for each pulse: zero or one. PAM4 doubles that, with four encoding levels for each pulse: zero, one, two or three. A full byte is encoded in two pulses, so eight bits of data are transmitted.

That sends more data coursing through the channel using existing hardware. PAM4’s downside is that data must be encoded, transmitted, then de-encoded when received, requiring additional processing. Still, PAM4 could break the current “connector density/speed paradigm.”

If higher-speeds are possible with existing hardware, imagine the possibilities of new ultra-high-speed, high-density connector solutions. In a Molex test, a zQSFP+ connector and a three-meter, high-speed cable assembly ran at 50 Gbps NRZ. Unlike standard cables, a high-speed cable helps minimize “suck-out,” or insertion loss, at certain frequencies.

These new components need new specs that examine performance of the overall channel – not just individual components. For example, QSFP28 connectors, such as the Molex zQSFP+, are used in 25 Gbps specs. But conservative industry “rules of thumb” prevent them from reaching their full speed potential. For example, the extra buffers typically used on components in the chain are not always needed.

When recreating the fictional Steve Austin in “The Six Million Dollar Man” TV show, his developers noted, “We can rebuild him… we have the technology.” The electronics industry also has the technology… to reach higher data transmission speeds. With better understanding of components, it’s time to move beyond today’s overly conservative standards into the future of high-speed data transmission.