Most popular breakthrough passive cable bottleneck

Breaking through the bottleneck of passive cables, active cables extend the transmission distance by three times

with the continuous increase of interconnection density in high-performance computing and data centers, designers are starting to solve the inherent unsolvable problems of passive cables

large bundles of copper cables with limited transmission distance will hinder the upward movement of air pushing the platen and upper beam (upper jaw seat), increase the weight of cables, and usually complicate cable management and wiring. One way to solve this problem is to use thinner cables, such as thinner cable specifications. However, the thinner the cable, the more serious the attenuation of the signal

"the cable should not be too thin and need to support a longer distance. In this way, when the data rate is high, there will be an interconnection problem that cannot be solved by the passive cable: the signal is extremely attenuated and severely deformed, so that the system cannot reliably restore it." John Mitchell, engineering director of quellan's poor use of marketing and application technology

in order to solve the problem of signal attenuation and deformation in the data center, quellan has developed a technology called q:active, which restores the signal quality by amplifying the signal and reducing the noise. Q: The active component is integrated into each end of the passive cable assembly, which amplifies the signal and reduces the noise, thereby significantly reducing the cable specification and extending the transmission distance. After adopting this technology, the transmission distance can reach three times that of the original passive cable

in addition to quellan, several companies such as W.L. Gore & Associates, Luxtera, Zarlink semiconductor and Intel are providing high-performance active cable interconnection for data centers. Their products can reduce power consumption, expand distance and improve speed

quellan's q:active scheme for extending the coverage distance of copper cable is reflected in three aspects. First, a low-power equalization filter is used to compensate the loss of dielectrics and wires in the cable. Secondly, a comprehensive set of path management features that enable the dehumidification capability to fall ensure that it fully meets a variety of high-speed data transmission protocols, including Infiniband, PCIe, 10GbE and SAS. Finally, active cable assemblies that support q:active are less sensitive to near end crosstalk than passive cable assemblies, and the link length is much longer than the distance limited by the signal-to-noise ratio (SNR) of traditional passive cables

quellan's products include three types: qlx4300-s40 3.125gbps four-way extended active copper cable; Qlx4600-s30 6.25gbps four way extended active copper cable; 6.25gbps four way extended active copper cable with Los support

these devices can be combined with Gore's advanced cable technology to provide data centers with quellan's so-called light multi force resolution, which can reach nearly 1/100000, much finer, and much more distant connection schemes. Quellan and gore reached an agreement last September. They will solve the huge cable bundle problem by providing OEMs and integrators with Gore extended reach cable assembly using q:active, which adopts Gore's eye opener+ patented conductor technology. The transmission distance of the cable scheme, which combines the advantages of the two technologies, is three times that of the passive cable, and its weight and volume are only 1/3

Figure 1: Gore's extended reach cable assembly adopts its patented eye opener+ wire technology and quellan's q:active device. The transmission distance of this cable is three times that of passive copper cable, and its weight and volume are only 1/3 of the latter

"Gore's eye opener+ wire technology, combined with its low loss dielectric material, can provide a signal fidelity that can open the eye diagram and reduce cable jitter." W. Kristina Mitchell, a product expert at L. Gore & Associates, said, "then quellan's q:active chip can process this clean but weak signal and reproduce it at the receiving end of the parallel cable."

according to gore, the distance that its cable can reach is 20 to 30% farther than the SPC cable of its competitors. In other words, it can achieve the same distance with SPC with finer cable specifications. In addition, the power consumption of each end of its extended reach cable assembly is 0.25W, while that of its competitors is 1 to 2W

choose optical cables

while Intel and Luxtera follow the path of optical active cables. Luxtera's optical active cable is connected to the same connector as the copper cable, and converts electrical signals into optical signals in the connector. It uses optical cables thinner than copper cables

the transmission distance of passive 4 x 10Gbps copper cable is limited to about 7 meters, while Luxtera's Blazar series optical cable can reach 300 meters. Blazar is a 40Gb optical active cable. Each channel of this four channel multi rate optical cable can work in At any rate within 5GB, the total bandwidth can reach 42gbps. Blazar is Luxtera's first product based on its patented CMOS photonics intellectual property (IP), which is implemented on a single bare chip, using the standard 0 13 micron SOI COMS process

in 40Gbps bandwidth, the speed and distance (up to 300 meters) of Blazar are twice and three times that of existing optical cable products respectively. It is encapsulated in the size of a qsfp connector, thereby increasing the density of the front panel by four times. The power consumption of each 40Gbps transceiver is 2.2 W, about half of that of 10Gbps optical fiber transceiver, Luxtera said

in June, Intel introduced Intel connect cable optical active cable with integrated transceiver. The optical cable has four 5Gbps channels in each direction, with a total bidirectional throughput of 20gbps. These 5Gbps channels support Infiniband DDR data rates, but can also work at lower data rates to support SDR and 10Gbps Ethernet CX4 devices that can get power from CX4 slots. Intel said that the price of the optical cable is roughly the same as that of copper cable, but the distance can reach 100 meters

Figure 2: Luxtera's optical active cable is connected to the same connector as the copper cable, and converts electrical signals into optical signals in the connector. Luxtera's Blazar series optical cables can be extended to a distance of 300 meters

Zhuolian semiconductor recently released an optical cable interconnection, which can expand the coverage distance of 10Gb Ethernet data centers and high-performance computer clusters. At present, 10GB Ethernet interconnection relies on CX4 connectors to connect copper cable assemblies for short distance requirements; Pluggable optical transceivers are used for long-distance requirements. It is said that the interconnection of zlynx optical cable can be 10 times longer than copper cable, and when the data center and computer cluster are expanded, the use of this ultra-fine optical cable will no longer be troubled by weight, flexibility and power consumption

zlynx product is an optical fiber cable with integrated industry standard electrical terminals, which can realize 20gbps bidirectional transmission and 5Gbps duplex four channel data transmission up to 100 meters. Zlynx standard connectors allow this optical solution to utilize CX4 ports. The typical power consumption per node of zlynx technology is 1W, while the power consumption per node of the latest copper technology is about five times that of 10GBASE-T, Zarlink said. (end)