D/A converter provides 11-bit, 2.5-GSPS and supports 20 times higher QAM channel density

February 13, 2012 // By Paul Buckley
Analog Devices has introduced an 11-bit D/A converter that enables cable television and broadband operators to synthesise the entire cable spectrum up to 1 GHz into a single RF port, while consuming a maximum of 1.1 W of power.

The AD9737A 2.5-GSPS D/A converter’s wide bandwidth and dynamic range enable cable infrastructure designers to increase QAM (quadrature amplitude modulation) channel density by 20 times over present cable modem implementations, enabling improved next-generation services such as interactive television, high-definition broadcasts and new speciality channels.

The AD9737A D/A converter features low noise and intermodulation distortion to enable high quality synthesis of wideband signals up to 1 GHz, reducing the number of transmit DACs required in the typical cable plant. The device operates from 1.8-V and 3.3-V supplies for a total power consumption of 1.1 W maximum.

The AD9737A benefits from a dual-port interface with double-data-rate LVDS data receivers that support the maximum conversion rate of 2.5 GSPS.  A proprietary switching technique enhances dynamic performance.  The devices output current is programmable from 8.7 mA to 31.7 mA adding flexibility in interface options.