At the heart of most switch and router designs lies the switch fabric. It channels packet data to the destinations controlled by the line cards processing the packets. Switch fabrics performing above 2.5 Gbits/s are available, but the price is steep and the power consumption is barely acceptable. Analog Devices' ADSX-34 Synchronous Crosspoint IC combats those issues.
The ADSX-34, a new model in ADI's Xstream line, features a 34-by-34 fully differential, nonblocking switching matrix that can handle speeds up to 3.2 Gbits/s per port operation. Total power consumption with all I/Os active is a cool 4 W, compared to the 15 to 20 W of competitors. The device isn't protocol-sensitive, so it can handle asynchronous transfer mode, Sonet, Ethernet, and others (see the figure).
This CMOS chip features 34 ports, two of which can be used for loopback testing. Each channel has its own preemphasis and equalization circuits, clock and data recovery (CDR) and data retiming circuits, and a 128-byte FIFO memory. The device's in-band tag routing permits the reading of destination headers to facilitate rapid switch configuration.
Samples will be available in June. Contact ADI for pricing information.
Analog Devices Inc.
www.analog.com