The ADF4356 allows implementation of fractional-N or integer-N phase-locked loop (PLL) frequency synthesizers when used with an external loop filter and an external reference frequency. A series of frequency dividers at another frequency output permits operation from 53.125 MHz to 6800 MHz.
The ADF4356 has an integrated VCO with a fundamental output frequency ranging from 3400 MHz to 6800 MHz. In addition, the VCO frequency is connected to divide by 1, 2, 4, 8, 16, 32, or 64 circuits that allow the user to generate RF output frequencies as low as 53.125 MHz. For applications that require isolation, the RF output stage can be muted. The mute function is both pin- and software-controllable.
Control of all on-chip registers is through a simple 3-wire interface. The ADF4356 operates with analog and digital power supplies ranging from 3.15 V to 3.45 V, with charge pump and VCO supplies from 4.75 V to 5.25 V. The ADF4356 also contains hardware and software power-down modes.
