Building on its expertise in the ATM/POS/SONET/SDH arena, Vitesse Semiconductor Corporation announced the VSC8116 and the VSC8117 PHY transceivers with 8-bit serial-to-parallel and parallel-to-serial data conversion. These third-generation ICs provide 155Mb/s or 622Mb/s operation. They are ANSI, Bellcore, and ITU-T compliant physical layer devices that provide SONET/SDH switches, routers, hubs, and test equipment designers with ICs that are fully compatible with today's leading User Network Interface (UNI) ICs and optoelectronics modules.

The VSC8117 integrates an on-chip Clock Multiplication Unit (CMU) for high speed clock generation and a Clock and Data Recovery Unit (CRU). The CMU is selectable for 622Mb/s or 155Mb/s operation, and uses either a 19.44, or 77.76MHz external reference clock. The selectable CRU reference clock input allows flexibility for multiple clocking schemes such as loop timing and those used in repeater applications. The VSC8117 is for the designer who requires more versatility in a PHY IC's operation.

The VSC8116 fulfills the requirements of the majority of 622Mb/s PHY designers with a very low power dissipation of 1.0 watt typical. This IC delivers the same functions of the VSC8117 without the on-chip CRU and is more economical.

"Our proven track record of advancing 622Mb/s ATM/POS PHY chips technology started in 1994. The introduction of these new small footprint devices enables our customers to increase port density in their next generation systems." stated Tony Anderson, Vitesse marketing manager of ATM/IP products. "At the same time, we have taken ATM to 2.5Gb/s with the industries first UNI chip set supporting STS-48/STM-16 applications," continued Anderson. "Our goal continues to be to decrease the cost, complexity, and board space requirements of 622Mb/s and 2.5Gb/s ATM/IP PHYs. And help the high-end ATM/IP market more rapidly expand to meet accelerating WAN and LAN communications needs," concluded Anderson.

There is little that Vitesse needs to learn about the 622-Mbit/s world of SONET and ATM; they have established standards of excellence in their products that have led to many product successes. These third generation parts will do the same for them with the architecture that they have previously proven to work extremely well. Now the footprint is smaller and the power is lower; this will undoubtedly help to maintain Vitesse's leadership in this market

The provision of the additional clock and data recovery unit on the VSC8117 and the optional 5-V programmable I/O (for 5-V optical modules) will probably make it the part of choice for new designs, especially with such a small premium on the price.