Now in its 21st year, DesignCon is one of the largest annual gatherings of chip, board and systems designers in the country. Held last month at the Santa Clara Convention Center (just across Tasman Drive from Levi’s Stadium, home of Super Bowl 50 and the San Francisco 49ers) it combines technical paper sessions, tutorials, industry panels, product demos and an exposition; this year more than 160 exhibitors showed their wares in power management, signal integrity (SI), design verification and interconnection. Indeed, interconnects traditionally play a major role at DesignCon and this year’s event attracted more than 30 such manufacturers who focused mainly on higher speed, better SI and smaller form factors (aiming to do so without a concomitant loss of performance). In particular, connector suppliers are catering to telecom and data computing OEMs, who realize that to be competitive they must deliver ever-faster data rates, being mindful of the fact that higher speeds can produce insertion loss and degraded SI.
Here is some of what was new and notable in the connector space at DesignCon.
PCBs sometimes need to be reused or reworked. Traditional SMT connectors are permanently affixed, making it virtually impossible to reuse PCBs, and when an SMT termination fails, attempting to rework it creates a short. One alternative, press-fit mezzanine connectors, would allow reuse but they typically offer lower signal integrity. According to Molex, its NeoPress System solves these issues by providing compliant-pin termination while minimizing near-end and far-end crosstalk, matching the signal integrity of its NeoScale SMT connectors. What is more, Molex says the compliant pin allows designers to rework the board and maximize system utility without sacrificing signal integrity.
The Molex NeoPress High-Speed Mezzanine System’s modular design is further said to achieve both high- and low-speed signals at 28 Gbps with tunable differential pairs (between 85 and 100 Ohms). Designers need only one connector for different speeds; therefore, they can save space on the PCB.
At DesignCon Molex also unveiled its Impel Plus backplane connectors, which are engineered to upgrade the company’s standard line of Impel backplane connectors, improving data speeds from 40 Gbps to 56 Gbps. The upgrade in connection speed will allow OEMs to avoid possible data slowdowns and prepare for future network upgrades. An extension of its Impel Backplane Connector family, Impel Plus connectors include grounding tail aligners and smaller signal compliant pins. The signal beam design of these connectors is said to improve insertion loss compared to in-line beams and pushes interface resonance frequency past 30 GHz. Because the connectors are backward and forward compatible, OEMs can meet future data rate needs without replacing infrastructure. These new connectors are well-suited for applications in several markets, including telecom and networking (hubs and servers); medical (patient monitoring), and aerospace/defense. According to Molex, Impel Plus connectors are compliant with IEEE 100GBASE-KR, 100GBASE-KP and the Optical Internetworking Forum (OIF) CEI-25G-LR specifications.
To increase signal density on the I/O panel TE Connectivity offered its micro quad small-form-factor pluggable (microQSFP) high-speed I/O connectors. Providing QSFP28 connector functionality for networking equipment, but in a smaller form factor with 33% higher density, microQSFP allows designers to fit up to 72 ports on a standard 1RU line card, saving substantial design space. In addition, microQSFP proponents claim significantly better thermal performance than other pluggable solutions on the market today, requiring less energy to cool networking equipment and increasing the ease of system thermal design. TE Connectivity says it was first to develop microQSFP connectors and cages in accordance with the new specification released by the microQSFP Multi-Source Agreement (MSA) group on January 15. The company expects to have standards-compliant products in the market during the first half of 2016.
AirBorn announced enhancements to its HD4 Interconnect Solution. HD4’s copper cable assembly advancements include "inverted T" termination on the board mount connector for improved PCB assembly and the option of solid conductor wire in addition to stranded wire, enabling a longer reach and better signal integrity at a lower cost due to, the company reports, enhanced manufacturing processes. These design modification are said to reduce overall costs by eliminating potting, while also increasing signal integrity and routing times. Additional advances include an improved backshell casing to reduce EMI/EMC, improved longer latch for positive engagement, improved strain and bend relief and UL, CSA and RoHS certification.
The RCx Multi-Source Agreement (MSA) was announced during DesignCon. It included the formation of a four-member industry working group aimed at defining and promoting adoption of a new intra-rack connection standard. This group, led by RCx founding members Amphenol, Broadcom, Dell and Hewlett Packard, has put forth a proposed RCx connector and cable system designed specifically for rack-based interconnect, providing simple, low cost, low power options for 25/50/100 Gbps connectivity. RCx is a passive, copper only, modular and high-density cabling scheme for server adapters and network switches. There are three RCx configurations – RCx1, RCx2 and RCx4, providing 25 Gbps (25Gx1), 50 Gbps (25Gx2) and 100 Gbps (25Gx4) connectivity, respectively.
The streamlined RCx MSA design is said to eliminate the need for active electrical components like EEPROMs, optics, re-timers, and management ICs; it is also said to simplify the electrical design of switches and adapters and significantly reduce the cost of the overall system solution.
