Chipset Delivers 10-Gb/s Line Card Design Solution April 2000 Issue Published Date: April 01, 2000
A complete 10-Gb/s line card for OC-192/STM-64 SONET/SDH transmissions is said to reside in a four-chip set that includes the: VSC7990 10-Gb/s laser driver; VSC8171 10-Gb/s, 16:1 mux with clock generator; VSC8172 10-Gb/s 1:16 demux with clock recovery; and VSC9116 STS-192 transport terminating transceiver (see photo). The VSC7990 chip boasts of very fast edge rates and high modulation current, reportedly opening the way for the design of efficient OC-192/STM-64 transmitters for all communication link distances. The IC has rise and fall times of <35 ps, very low jitter, and supports operation at 10.7 Gb/s, allowing for forward error correction (FEC) and boosting signal integrity. And it operates from a 5V or -5.2V supply, dissipates <800 mW, and costs under $150 each/5000. The VSC8171 multiplexer with clock multiplication unit (CMU) integrates a high-speed clock output to re-clock data at the laser driver or to verify jitter performance to ensure SONET compliant data output. And the VSC8172 demultiplexer integrates the clock and data recovery functions. The mux comes in 80-pin PQFPs and the demux in 100-pin PQFPs, with each IC costing $250 each/1000-- both devices also come in 96-pin BGA packages. The VSC9116 transceiver is designed to perform section and line termination functions, to monitor system performance of STS-192 data transmissions, and to enhance byte interleaving/deinterleaving of STS-48 data streams. This 2.5V IC dissipates only 8.5W and costs $445 each/5000 in 720-pin CBGAs.
