Date: 28/02/2011

2.5-GSPS 14-bit DAC for designing wireless and cable apps

Analog Devices, Inc. has introduced AD9739A TxDAC14-bit, 2.5-GSPS D/A converter IC. ADI says this chip due to its high bandwidth can increase QAM (quadrature amplitude modulation) channel densities by 20 times over today's cable modems, so that 1 GHz spectrum can be synthesized into a single RF port at a power consumption of 1.1 Watts. ADI claims competing DAC chips require an additional 28 LVDS (low-voltage differential signaling) pairs for the data interface and consume nearly three times the power of ADI's AD9739A D/A converter.

"The AD9739A allows cable head-end equipment manufacturers to simplify and reduce their signal chain footprint while enabling operators to continue providing their customers with improved next-generation services, such as interactive TV, high-definition broadcasts and new specialty channels," said Chris Jacobs, product line director, High-speed D/A Converters, Analog Devices. "Synthesizing the entire cable spectrum into a single RF port increases the number of QAM channels per D/A converter by up to 20 times to meet cable infrastructure demands while significantly lowering power consumption and system cost."

The other key features of this device are:

1.Supports the high-fidelity digital synthesis of RF signals at up to 3.6 GHz.
2. Eliminates a low-pass filter and one mixer or modulator stage in wireless equipments by using single channel DAC architecture.
3. The AD9739A is suggested for applications including wireless-communications equipment, instrumentation and defense electronics.
4. Provides multi-carrier capability up to the Nyquist frequency in baseband mode and uses the mix mode function to generate RF signals in the second and third Nyquist zones.
5. Operates from 1.8V and 3.3V supplies for a total maximum power consumption of 1.1 W.
6. Low noise and intermodulation distortion performance enable high quality synthesis of wideband signals up to 1 GHz.
7. Dual-port interface with double-data-rate LVDS data receivers supports the maximum conversion rate of 2.5 GSPS.
8. Proprietary switching technique enhances dynamic performance.
9. Output current is programmable from 8.7 mA to 31.7 mA.

Package: 160-ball CSBGA
Availability: Now
Price: Each $43.69 for 1K pieces
Edtorial Product Rating: ** (Average Plus)