D/A converter increases QAM channel density by 20 times
1 min read
Analog Devices has launched an 11bit d/a converter enabling cable television and broadband operators to synthesise the entire cable spectrum up to 1GHz into a single rf port, while consuming a maximum of 1.1W of power.
According to ADI, the AD9737A 2.5GS/s d/a converter's wide bandwidth and dynamic range enable cable infrastructure designers to increase quadrature amplitude modulation (QAM) channel density by 20 times over present modem implementations. This, says ADI, enables improved next generation services such as interactive television, high definition broadcasts and new speciality channels.
The device's low noise and intermodulation distortion are designed to enable high quality synthesis of wideband signals up to 1 GHz, reducing the number of transmit d/a converters required in a typical cable plant. It operates from 1.8 and 3.3V supplies for a total power consumption of 1.1W maximum, while dual port interface with double data rate LVDS data receivers support the maximum conversion rate of 2.5GS/s. Additional features include a proprietary switching technique designed to enhance dynamic performance and a programmable output current from 8.7 to 31.7mA.
