New DDS family delivers high clock speed with record low power dissipation.
Analog Devices expanded the company's already extensive portfolio of radio frequency (RF) ICs with a new family of direct digital synthesizers (DDS). The new chips deliver a 400 MHz clock speed at one-tenth the power consumption of previous solutions. This now enables designers to use DDS for fast frequency hopping at higher output frequencies in more power-sensitive applications. DDS, which is the technique of digitally creating and manipulating sine waves—or other continuous wave forms—in the digital domain, is the preferred technology for applications requiring superior digital frequency agility, output phase control, and excellent phase noise performance. Typical applications include satellite communications, broadband networking, radar, test and measurement, and instrumentation.
The new DDS devices are the first in the industry to clock at 400 MSPS and synthesize frequencies of up to 160 MHz while dissipating less than 200 mW of power. Previous DDS chips of comparable resolution could only synthesize frequencies up to 120 MHz and dissipated 2 watts of power. The lower power dissipation now allows designers to use multiple chips on a single PCB with less concern for thermal issues. Additional features of the family include an integrated 14-bit digital-to-analog converter, on-chip random access memory (RAM), phase offset and amplitude control, and multi-chip synchronization.
The new DDS family comprises four new 14-bit devices with various added benefits. The feature sets were selected to allow designers to purchase only the functionality needed for the desired application. The four family members and added functionality are the following:
- AD9951: Basic DDS with on-board 14-bit DAC
- AD9952: with high-speed comparator
- AD9953: with RAM (allows nonlinear phase / frequency sweeping)
- AD9954: with high-speed comparator, RAM, and automatic linear frequency sweep
Leadership Speed and Power Efficiency - More About the AD9954
As the flagship product in the new DDS family, the AD9954 features a 14-bit digital-to-analog converter operating up to 400 MSPS, as well as a high-speed comparator, RAM, and automatic linear frequency sweep. The chip is digitally programmable and is a complete high-frequency synthesizer capable of generating a frequency-agile analog output sinusoidal waveform at up to160 MHz. The AD9954 is designed to provide fast frequency hopping and fine-tuning resolution (32-bit frequency tuning word). The frequency tuning and control words are loaded into the AD9954 via a serial I/O port. The AD9954 includes an integrated 1024x32 static RAM to support flexible frequency sweep capability in several modes. The AD9954 also supports a user-defined linear sweep mode of operation. The AD9954 is specified to operate over the extended industrial temperature range of -40 degrees to +85 degrees C.
Pricing and Availability
All parts are available now in 48-lead EPAD-TQFP packages and are priced per unit in 1,000-piece quantities as follows: AD9951 - $13.75; AD9952 - $15.50; AD9953 - $14.75; AD9954 - $17.25.
