DSL chips run at 10Mbit/sec

Zarlink Semiconductor has launched three IMA processing chips that achieve data throughput of 10 Mbit/sec – the industry’s highest serial DSL rate, according to the company.

Zarlink Semiconductor has launched three IMA (Inverse Multiplexing over ATM) processing chips that achieve data throughput of 10 Mbit/sec – the industry’s highest serial DSL rate, according to the company.

Designers are demanding multi-rate, versatile IMAs that can reliably process DSL traffic over ATM networks, while supporting the wide array of service rates, tariff options, and access aggregation requirements in global DSL markets. With Zarlink’s 4-port ZL30226, 8-port ZL30227, and 16-port ZL30228 IMA devices, designers can scale data rates on DSL subscriber links to individual service requirements, reaching 10 Mbit/sec.

Zarlink’s ZL30226/7/8 IMA chips perform two-way protocol conversions between cell-based ATM networks and serial TDM data streams over DSL subscriber links. Each on-chip TDM port supports data rates of up to 2.5 Mbit/sec, and a unique port aggregation feature enables serial data throughputs of up to 10 Mbit/sec over a single link.

The ZL30226/7/8 also offer support for a broad range of port density and IMA grouping requirements. The IMAs are pin-to-pin compatible, allowing designers to use the same DSL line card architecture to address different density requirements with simple device change-outs. A TDM ring interconnect allows up to six of the devices to operate as one, enabling the configuration of IMA groups from ports on multiple devices. On a per-chip basis, the 4-port ZL30226 supports up to four IMA groups, while the 8-port ZL30227 and 16-port ZL30228 support up to eight IMA groups.

The ports on the ZL30226/7/8 chips can also be individually configured for lower-layer ATM-to-TDM/TDM-to-ATM TC (transmission convergence) applications.

Zarlink’s IMA technology recently passed IMA assurance tests at the InterOperability Lab of the University of New Hampshire’s Research Computing Center, an independent ATM test facility. Zarlink also worked with two leading DSL chip vendors to ensure its new IMA devices interoperate with G.SHDSL transceivers. G.SHDSL, which stands for G.991.2 Single-pair, High bit-rate DSL, is the ITU-T’s (International Telecommunication Union-Telecommunications) global standard for high-speed DSL.

Zarlink’s new IMA chips are now in volume production. In quantities of 1K, the ZL30226 is priced at $48.00, the ZL30227 at $64.00, and the ZL30228 at $87.00. The devices are offered in pin-to-pin compatible, 384-ball PBGA (plastic ball grid array) packages and supported by DSL reference designs and software.