Small transceiver makes big splash

Small transceiver makes big splash

By GRACE F. MURPHY

Six companies are lending their support and dollars to a new small-form-factor transceiver designed to reduce circuit board space by up to 50% in fiber-optic data and telecommunications systems. The transceivers manufactured under the agreement will measure 0.535 inch wide, which is roughly half the size of standard transceivers today.

The six companies are amp Inc. of Harrisburg, PA; Hewlett-Packard Co. (HP) of Palo Alto, CA; Lucent Technologies, Murray Hill, NJ; Nortel, Brampton, ON, Canada; Siemens AG-Fiber Optics, New York City; and Sumitomo Electric Lightwave Corp., Research Triangle Park, NC.

Systems designers using the smaller transceivers can double port densities by fitting twice the number of transceivers onto the same board, which is intended to lower costs and design time. Systems standards supported by the agreement include Asynchronous Transfer Mode, Fiber Distributed Data Interface (fddi), Fibre Channel, Fast Ethernet and Gigabit Ethernet, Synchronous Optical Network, and Synchronous Digital Hierarchy.

Demand is great

Richard Mack, vice president of fiber-optics market research firm kmi Corp., Newport, RI, said in a prepared statement that there is great demand for transceivers in the data and telecommunications markets, particularly in high-speed applications. "The establishment of uniform package sizes and pin-outs from multiple component suppliers can contribute to lower equipment costs, increased demand for fiber-optic equipment, and higher production volumes. Previous efforts to agree on standardization or interchangeable components such as fddi modules and Fibre Channel optical-link modules have contributed to fiber-optics market growth, and this agreement is even broader in the number of applications that can be served with the compatible parts," he said.

Under the agreement, the companies will follow the same transceiver package outline and definition of pin functions for a circuit board layout. Variations of the transceivers will address data rates from 100 Mbits/sec to 1.5 Gbits/sec. The transceivers will start out with a 10-pin footprint, but systems with a 20-pin dual-inline device are in the works.

Yet while the agreement specifies the package dimensions, circuit board layout footprint, pin size, positioning, and functions of the transceiver, the choice of the connector that will link the transceiver to the optical network remains up to the manufacturer. The transceivers are designed to accept 8-pin modular jack type optical connectors. Current options include, but are not limited to, Lucent`s LC; the mt-rj developed by amp, HP, US Conec, Siecor, and Fujikura Ltd.; or ibm-Siecor`s sc/dc optical connectors. The mt-rj design was the only updated connector design to make it to a vote before the Telecommunications Industry Association`s (tia`s) 41.8.1 Commercial Building Cabling Standard Committee, where it was shot down in February (see Lightwave, March 1998, page 1.)

The tia vote--and the proprietary interest of individual manufacturers--means that users should be provided with a choice of connectors. For example, HP is already delivering its new transceivers, which use the mt-rj technology. HP is delivering the small-form-factor mt-rj transceivers to the 125/155-MBd markets. Customers include Cabletron Systems, Cisco Systems Inc., and xlnt Corp. HP expects to have gigabit devices for multimode and singlemode fiber available in the next few months. Parts would be based on 850-nm vertical-cavity surface-emitting lasers and 1300-nm Fabry-Perot laser technologies.

As of press time in early March, other companies that had stepped forward as mt-rj fiber-optic transceiver vendors were amp, HP, Siemens, Sumitomo, and Fujikura Ltd.

Meanwhile, Lucent is offering its 1417G5-, 1417H5-, and 1417J4-family of transceivers that comply with the terms in the multisource agreement signed by the six companies. Not surprisingly, Lucent`s transceivers carry the company`s LC connectors.

Siemens is presenting the small-form-factor transceiver with options for customers--with 3M`s Volition connector, with the standard sc/dc connector, and with a mt-rj connector. Nortel had not announced its connector plans as of press time. q