Microwave Journal
www.microwavejournal.com/articles/7156-adi-enhances-rf-if-signal-chain-performance

ADI Enhances RF/IF Signal Chain Performance

October 29, 2008

Analog Devices Inc. (ADI), a leader in high-performance semiconductors for signal processing applications, introduced the ADF4350 synthesizer with on-chip voltage-controlled oscillator (VCO) and phase-locked loop (PLL), which is the industry’s first fully integrated synthesizer to operate over an exceptionally wide continuous frequency range. ADI also introduced a family of highly integrated active and passive mixers that are ideally suited for use in diversity communications applications. The active ADL5802 and passive ADL5356, ADL5358 and ADL5360 dual-channel diversity mixers expand ADI’s portfolio of main and diversity products and when coupled with the ADF4350 provide a highly integrated two-chip diversity down conversion solution for cellular base stations, satellite communications and point-to-point microwave radio equipment.

The ADF4350 integrated synthesizer provides designers with a single, low phase-noise solution supporting a continuous tuning range from 137.5 MHz to 4.4 GHz. Alternative approaches require as many as 10 individual VCO/PLL combinations. The VCO in ADI’s new ultra-broadband, fully integrated synthesizer features phase-noise of –137 dBc/Hz at a 1 MHz offset when operating at 2.1 GHz, and –155 dBc/Hz at a 1 MHz offset when operating at 137.5 MHz. This corresponds to an integrated rms phase error of 0.36 degrees at 2.1 GHz and 0.02 degrees at 137.5 MHz. The ADF4350 provides two RF output ports and enables the user to digitally program the output power level.

The ADF4350 supports both integer-N and fractional-N operating modes, allowing the user to determine the optimal spur and phase-noise performance via software controls for optimal performance and faster time to market.