ADI's Low Power D/A Converter Synthesizes Entire Cable Spectrum into a Single RF Port

Analog Devices, Inc. (ADI), a leading manufacturer of semiconductors for signal processing applications and the data converter market share leader*, today introduced a 14-bit D/A converter that enables cable television and broadband operators to synthesize the entire cable spectrum up to 1 GHz into a single RF (radio frequency) port, while consuming a maximum of 1.1 W of power. The AD9739A 14-bit, 2.5-GSPS D/A converter's wide bandwidth and dynamic range enables cable operators to increase the QAM (quadrature amplitude modulation) channel densities by 20 times over the densities found in today's cable modems. Competing D/A converter solutions require an additional 28 LVDS (low-voltage differential signaling) pairs for the data interface and consume nearly three times more power than ADI's AD9739A D/A converter. Download data sheet and view product page: http://www.analog.com/AD9739A AD9739A D/A Converter: Multi-Standard Support for Cable and Wireless Infrastructure The AD9739A D/A converter features ADI's proprietary mix-mode function, which supports the high-fidelity digital synthesis of RF signals at up to 3.6 GHz. The combination of best-in-class, 2.5-GSPS bandwidth and 14-bit dynamic range with a direct-to-RF core allows broadband and next-generation wireless equipment designers to use a single-transmit D/A converter architecture that eliminates a low-pass filter and one mixer or modulator stage. The AD9739A converter is well suited for a broad range of applications, including wireless-communications equipment, instrumentation and defense electronics. The device provides multi-carrier capability up to the Nyquist frequency in baseband mode and uses ADI's mix-mode function to generate RF signals in the second and third Nyquist zones. AD9739A 14-bit, 2.5 GSPS D/A Converter Features and Benefits:

• Operates from 1.8-V and 3.3-V supplies for maximum power consumption of 1.1 W.
• Low noise and intermodulation distortion performance enable high quality synthesis of wideband signals up to 1 GHz.
• Dual-port interface with double-data-rate LVDS data receivers supports the maximum conversion rate of 2.5 GSPS.
• Proprietary switching technique enhances dynamic performance.
• Output current is programmable from 8.7 mA to 31.7 mA.

Complementary components include ADI's high-speed, low-jitter clock generation and distribution products, such as the ADCLK914 high-speed SiGe clock buffer. This product drives the clock input to the AD9739A converter with a 2-V differential swing that achieves jitter performance of 110 fs (femto seconds). Please visit us at: http://www.analog.com