Norwood,MA -- Analog Devices, Inc. a provider of high-performance semiconductors for signal processing applications, enabled faster, smarter radio frequency (RF) synthesis systems by introducing the industry's first low cost, low power, monolithic solution to integrate both direct digital synthesis (DDS) and phased locked loop (PLL) circuitry. The AgileRF synthesizer is designed for low-power applications such as radar systems used in automobiles, marine and military equipment, as well as satellite communications and instrumentation that benefit from highly linearized frequency and phase sweeping at RF frequencies. It is capable of operating within the ISM (industrial, scientific and medical), band of frequencies which is widely used in a broad spectrum of electronic equipment, and localized, low power applications ranging from garage door openers to gaming systems to home security systems.
The AD9956, the second member of ADI's AgileRF synthesizer family, offers increased functionality and reduced costs in systems requiring phase and frequency agility and exceptional resolution at RF frequencies. These systems include fine-tuning LO generation, radar, low-jitter clock generation, and frequency & phase modulation applications. Using less board space and fewer components, the device reduces system cost by up to 20 percent compared to traditional designs using multiple DDS, PLL, and clock driver components.
Among the AgileRF synthesizer's unique features is its narrow linear frequency sweep, which allows radar systems to use the principle of pulse compression. The synthesizer enables simple, highly linearized radar sweeps by generating a precision clock for the DDS. This can be used to generate ramped frequencies up to 2.7 GHz, something which cannot be done using a DDS alone. The scaleable charge pump current feature allows user-defined control over loop-bandwidth -enabling the system designer to change loop bandwidths through software. The device also contains multiplexers that enable different synthesizer configurations, minimize the need for custom hardware designs, and simplify the design, prototype, and development stages.
The AD9956 is comprised of advanced DDS and PLL circuitry, as well as a 650 MHz PECL-compliant CML clock driver with programmable slew rates. The DDS component features a 14-bit digital-to-analog converter operating up to 400 MSPS, and an advanced phase-detector/ charge pump combination that, when configured with an external VCO, enables the synthesis of digitally-programmable, frequency-agile analog output sinusoidal waveforms at up to 2.7 GHz. The PLL circuitry includes a phase detector with scaleable 200 MHz inputs (pre-scaler inputs operate up to 650 MHz) and digital control over the charge pump current.
The AD9956 is designed to provide fast frequency hopping and fine-tuning resolution (48-bit frequency tuning word). The frequency tuning and control words are loaded into the AD9956 via a serial I/O port which has a device write speed of 25 Mbit/sec. The device's DDS block also supports a user-defined linear sweep mode of operation. The AD9956 is specified to operate over the extended automotive temperature range of -40 degrees C to +125 degrees C.
The AD9956 is sampling now in 48-lead LFCSP (lead form chip scale) packages, and will be available in full production in June 2004. The AD9956 is priced at $17.25 per unit in 1,000-piece quantities.
AgileRF AD9956 data sheet