Conexant Builds Set-Top Bonds


Looking to keep pace with silicon rival Broadcom, Conexant Systems last week introduced a high-powered, integrated chip set that can bond three downstream cable-modem channels.

The CX2445X chip's key feature: It has three demodulators with a downstream data channel-bonding capability, which Conexant said would let operators provide up to 120 Megabits per second of bandwidth to a subscriber's set-top. That means it could easily handle several streams of high-definition video over an Internet Protocol network.

Conexant positioned the new chip set, aimed at next-generation cable boxes, as the first in a family of Data Over Cable Service Interface Specification “2.0-plus” silicon for cable modems.

In other words, it provides some of the functions of CableLabs' DOCSIS 3.0 spec, which will provide channel-bonding capability both upstream and downstream.

The product represents “our renewed commitment to developing leading-edge solutions for the cable set-top marketplace,” Lewis Brewster, executive vice president and general manager of Conexant's Broadband Media Processing business unit, said in a statement.

Conexant said it is aiming the CX2445X chip set at set-top boxes with digital video recording capabilities, as well as basic two-way set-tops and DOCSIS cable modems used in bidirectional networks.

The chipset follows fast on the heels of Broadcom's launch last month of the BCM7118 single-chip silicon product, which can similarly bond three channels together and also is aimed at set-tops that provide IP video services.

The CX2445X is sampling now, with volume production scheduled for the third calendar quarter of 2007. The chips will be priced at $17 each in production quantities, according to Conexant. Meanwhile, Broadcom hasn't announced pricing of its channel-bonding chipset or when it expects to ship in volume.

In its announcement last week, Conexant didn't disclose any set-top partners for the chip set. But in November, the company said Motorola had chosen certain of its multimedia and networking processors for use in a forthcoming next-generation set-top product. Motorola provided scant details about the planned box, saying only that it is “intended to offer consumers a more flexible and compelling entertainment experience” and will have home-networking capabilities.