Analog Devices Introduces Two New Multichannel DDS Devices

Norwood, MA -- Analog Devices Inc. announced two new DDS (direct digital synthesis) devices, providing a solution to two common design challenges faced by system engineers in a range of applications. Allowing independent programming of up to four inherently synchronized outputs, ADI's new four-channel AD9959 and two-channel AD9958 deliver greater control to correct imbalances between multiple signals. For space-constrained systems, the AD9958 and AD9959 simplify the design process by integrating multiple DDS channels on a single chip. Direct digital synthesis is a digital technique used for generating an analog output waveform or clocking signal from a fixed-frequency clock source. The AD9959 and AD9958 are optimized for applications that require complex high speed synthesis up to 200 MHz, including phased-array radar/sonar systems, automatic test equipment, medical imaging and optical communications systems.

"Analog Devices is meeting the synthesizer synchronization challenge by leveraging its world-class converter technologies to develop highly-integrated DDS devices that lower the cost and complexity of system design," said Kevin Kattmann, product line director, high speed converter group, Analog Devices. "The ability to easily achieve precision phase offset control between multiple synchronized output channels, while consuming minimal board space, enables the AD9959 and AD9958 to offer system designers significant advantages over traditional frequency synthesizer solutions and single-channel DDS products."

In order to alleviate the design complexities typically involved in the synchronization of multiple DDS devices, the independent channels of the AD9959 and AD9958 are internally synchronized by a common reference clock. Programmable channel control allows for correction of imbalances in external signal paths due to analog processing, such as filtering, amplification, or PCB layout mismatches. If additional channels are required, the AD9959 and AD9958 allow daisy chaining of additional DDS chips. The devices also offer extremely low power consumption of less than 165 mW per channel.

Each channel of the four-channel AD9959 and the two-channel AD9958 incorporates a high speed 10-bit DAC with excellent wideband and narrowband SFDR (spurious free dynamic range). Each fully independent programmable channel provides 14-bits of phase offset tuning, 32-bit frequency resolution and 10-bit amplitude control. The device also supports direct or linear sweep modulation, while achieving channel isolation of greater than 60 dB. The integrated 32-bit frequency tuning word enables each channel to be programmed to resolutions of 116 mHz or less with a sampling clock of up to 500 MSPS.

The AD9959 is available in production quantities now; the AD9958 is sampling now with product quantities available in September, 2005. Both devices are specified over the extended industrial temperature range of –40 degrees C to +85 degrees C.

SOURCE: Analog Devices