Ultra-Fast Switching, High Performance PLL Frequency Synthesizer

This demo shows a novel PLL circuit design using ADI’s quadband VCOs comprised of four narrow bands integrated into a single package. This design delivers the benefits of the frequency range of wideband PLLs, as well as the phase noise performance and lock time of narrowband PLL performance. An on-board active loop filter circuit has been designed for optimal phase noise performance across the four frequency bands of the quadband VCO. Control circuitry has been designed for fastest switching time between bands. A phase resync feature is also demonstrated for phase critical applications such as beamforming.