- News
9 March 2012
Molex partners with Altera and Gennum to demo 28G VSR interconnect interoperability
At the Optical Fiber Communication Conference & Exhibition/National Fiber Optic Engineers Conference (OFC/NFOEC 2012) in Los Angeles this week (6-8 March), Molex Inc partnered with Altera Corp and Gennum Corp to demonstrate interoperability of a 28Gbps Very Short Reach (VSR) interconnect solution during the Optical Internetworking Forum (OIF) ‘Interoperability 2012 – Enabling High-Speed Dynamic Services’ multi-vendor showcase.
“By demonstrating interoperability of a 28Gbps system, Molex and partners Altera and Gennum are paving the way for next-generation, high-speed connectivity,” says Molex’s group product manager Scott Sommers. “This is a critical step in meeting the high-performance needs of future bandwidth-intensive communications systems,” he adds.
The demonstration tested the 28Gbps transmission technology over 2km of single-mode fiber using Molex’s silicon photonics-based transceiver and zQSFP+ interconnect system. The channel included PRBS31 data at 28.05Gbps within the Altera Stratix V GT FPGA (field-programmable gate array), which is tailored to support the most bandwidth-intensive communications systems. The data was then transmitted over a Gennum VSR host channel with 12dB of insertion loss, through a zQSFP+ connector to Gennum clock & data recovery (CDR) integrated circuits. The re-timed outputs of the CDRs were transmitted to the Molex 1490nm 4x28G Optical Transceiver Module, looping the optical data back to its receiver through 2km of single-mode fiber. In the receive direction, the data flow was in the reverse order through the cascaded blocks, ending at the PRBS31. The error checkers within the Altera FPGA verified that the entire transmit and receive data path through the system was operating error free. An electrical data eye was shown on a Tektronix DSA8300 digital sampling oscilloscope at one of the Gennum CDR outputs.
Molex’s zQSFP+ system supports next-generation 100Gbps Ethernet and 100Gbps InfiniBand enhanced data rate (EDR) applications with what is claimed to be excellent thermal cooling, signal integrity (SI), electromagnetic interference (EMI) protection and low power consumption.
Altera’s Stratix V FPGAs deliver what is claimed to be the highest system bandwidth at the lowest power consumption (under 200mW per transceiver at 28Gbps). They support backplane, chip-to-optical module and chip-to-chip applications through 28Gbps transceivers, and up to 66 full-duplex 14.1Gbps transceivers. The transceivers provide what is claimed to be the industry's highest system reliability and performance with the lowest jitter.
By re-setting the jitter budgets within the module in both the transmit and receive directions, Gennum’s CDRs enable robust operation for new systems such as Nx25G active optical cables (AOCs) and 100GBASE-LR4/ER4 and OTU4 optical modules. In the transmit direction they provide laser drivers with very low-jitter signals, allowing clean, wide-open transmit eyes. In the receive direction they remove jitter from the recovered optical signals, promoting error-free reception by a downstream ASIC (application-specific integrated circuit) receiver on the host board. The GN2425 and GN2426 CDRs include equalization capability beyond that demanded of the draft Common Electrical Interface CEI-28G-VSR IA (implementation agreement), providing a robust VSR link.