Vitesse Semiconductor Corporation announced the latest additions to its 2.5Gb/s ICs product line for SONET/SDH & Wavelength Division Multiplexing (WDM) system designers - the VSC8150, a SONET/SDH transport overhead protocol monitor, and the VSC830, a dual 2.5Gb/s 2x2 crosspoint - the first products of their kind. These ICs provide network management capability for 2.5Gb/s SONET/SDH terminal, WDM and digital cross connect switch equipment. Today, most SONET/SDH overhead management functions are performed with expensive ASICs that require time-consuming development cycles. Using the VSC8150 and VSC830, the majority of overhead monitoring is performed at line speed. When coupled with a simple and inexpensive FPGA, designers can develop higher performing SONET/SDH equipment in less development time and with a lower cost.

The explosion of digital data transmitted via the Internet, fax/modems and dedicated lines demands manageable network bandwidth in SONET/SDH systems, particularly WDM equipment. The signal quality delivered by Vitesse's high bandwidth GaAs digital technology eclipses the performance of other potential solutions with no cost premium. Vitesse is the leading independent supplier of 2.5Gb/s SONET/SDH ICs and, since 1989 has continually driven down the power consumption and price of these components while increasing their integration. Vitesse's new fabrication facility in Colorado Springs is increasing the availability of 2.5Gb/s ICs, leading to simpler and more cost-effective 2.5Gb/s designs. This coincides with the dramatic increase in deployment of 2.5Gb/s WDM systems in telecom applications and the interests shown in this technology by datacom equipment vendors.

"The VSC8150 and VSC830 are the first devices specifically designed for the needs of optical networks, and complement our existing line of 2.5Gb/s products, such as mux/demux chipsets, voltage and laser drivers, post amplifiers, and transimpedance amplifiers," stated Andrew Schmitt, telecom marketing engineer. "Design engineers can now design a complete board that multiplexes from lower speed data paths to 2.5Gb/s SONET/SDH optical links using highly integrated and cost effective ICs from Vitesse," continued Schmitt.

VSC8150 SONET/SDH Overhead Monitor The VSC8150 monitors the integrity of a SONET/SDH signal and provides a slim solution for implementing operation, administration, management, and provisioning (OAM&P) features in WDM equipment and optical crossconnects. The SONET/SDH signal is received and retimed for output at rates up to 2.488Gb/s, and is also de-multiplexed internally for processing by standard cell logic. This processing provides indication of SONET/SDH frame status (SEF/LOF), received bit errors (B1 Parity error detection), and allows the user to inspect the contents of the SONET transport overhead. Results of this processing are output from the part using 6MHz TTL, enabling the user to implement OAM&P using programmable logic devices and eliminating the need for extensive ASIC developments. The VSC8150 can be provisioned to analyze STS-48/STM-16, STS-12/STM-4, and STS-3/STM-1 signals, while the retimed data output functions up to frequencies of 2.488Gb/s.

"The VSC8150 combines the functions of a discrete high speed demultiplexer and a custom ASIC into a single package, reducing the complexity and cost of the system board," stated Schmitt. "The VSC8150 is the first high performance device available that is designed specifically for the needs of WDM system designers, allowing them to more easily and quickly construct equipment with rate-independent features and the ability to participate in the SONET/SDH management infrastructure," continued Schmitt.

VSC830 2.5Gb/s Dual 2x2 Crosspoint The VSC830 contains two independent 2x2 crosspoints, each one allowing two differential PECL outputs to select from either of two differential PECL inputs. The 2:1 multiplexer tree architecture allows the splitting and selecting of OC-48 signals, or allows two OC-48 signal inputs to be cross-switched among two outputs. The dual 2x2 configuration allows one package to perform protection switching on the port card. Two crosspoints switch incoming and outgoing service and protection signals serially. Dual configuration also allows one package to provide an asynchronous bypass of a clock and recovery unit, an important function for implementing rate-independent WDM systems. As such, the VSC830 is ideally suited to work with the VSC8150 in 2.5Gb/s WDM applications. The VSC830 provides high bandwidth and low skew to switch both a 2.5Gb/s signal and 2.5GHz clock; allowing data and the accompanying clock to be switched through the same fabric.

The back-terminated PECL output drivers of the VSC830 provide excellent signal integrity in a 50 ohm transmission line environment, and can be individually powered off to reduce unnecessary power consumption. The switch fabric generates less than 40ps of peak-to-peak jitter and exhibits less than 50ps of skew between outputs. Selection pins can be either TTL or ECL levels.

"SONET/SDH architecture is dominated by 'pairs' of signals that need to be split, selected, or switched. The VSC830 accomplishes this in a small footprint at up to OC-48 rates," stated Schmitt. "While optical crossconnects with electrical switch fabrics and WDM equipment use this function, designers of 1Gb/s systems, such as Gigabit Ethernet or Fibre Channel subsystems, in a variety of markets may find a unique use for the VSC830," continued Schmitt.

With these two parts, Vitesse has completed the chain for each end of a SONET/SDH path, replacing -- with the monitor -- a complex ASIC operating at frequencies ASIC designers have not been used to working at. The VSC8150 is a neat but expensive solution to those problems, but the cost of a single component is small compared to project costs in this area. The VSC830, on the other hand, is one of those ubiquitous parts that, in this case, solves splitting and switching problems for pairs of high-frequency signals up to the designed SONET/SDH frequency use. The jitter and skew numbers are also great for a large variety of uses from DTV signals upwards. And I love the provisioning for both TTL and ECL levels. There are so many possible communications applications that this part could be used for that this could well become the largest volume part that Vitesse has ever produced. But the price is high for that kind of universal adoption and Vitesse will have to move on it or be willing to do so for true volumes.

The VSC8150 is in a 100-pin 14 mm PQFP and is in production. It operates with a single 3.3-V rail or operation may be split with a combination of 3.3 V and 2 V. It is priced at $150 in 1000-piece lots. The VSC830 is in a 44-pin 10 mm PQFP and is sampling now. It is priced at $55.00 in 1000-piece lots.