Microwave synthesizer ADF4368

PLLfrequencyultra-low phase noise

The ADF4368 is a high performance, ultra-low jitter, integer-N and fractional-N phase-locked loop (PLL) with integrated VCO ideally suited for frequency conversion applications. The high performance PLL has a figure of merit of −239 dBc/Hz, very low 1/f noise of normalized −287 dBc/Hz and high PFD frequency that can achieve ultra-low in-band noise and integrated jitter. The ADF4368 can generate any frequency from 800 MHz to 12.8 GHz without an internal doubler, which eliminates the need for sub-harmonic filters. The Σ-Δ modulator includes a 25-bit fixed modulus that allows hertz frequency resolution and an additional 17-bit variable modulus, which allows even finer resolution and flexibility for frequency planning. The 9 dBm output power at 12.8 GHz in single-ended configuration with 16 step power adjust feature makes it very useful for any application. For multiple frequency conversion applications, such as phase array radar or massive MIMO systems, the outputs of multiple ADF4368 can be aligned by using the SYNC input or EZSync™. The EZSync method is used when it is difficult to distribute the SYNC signal to all devices precisely. For applications that require deterministic delay or delay adjustment capability, a programmable reference to output delay with <1 ps resolution is provided. The reference to output delay is guaranteed across multiple devices and temperature, allowing for predictable and precise multichip alignment. The simplicity of the ADF4368 block diagram eases development time with a simplified serial-peripheral interface (SPI) register map, external SYNC input, and repeatable multichip phase alignment both in integer mode and fractional mode.