The ADF4002 frequency synthesizer is used to implement local oscillators in the up-conversion and down-conversion sections of wireless receivers and transmitters. It consists of a low-noise digital phase frequency detector (PFD), a precision charge pump, a programmable reference divider and programmable N divider. The 14-bit reference counter (R counter), allows selectable REFIN frequencies at the PFD input.
A complete phase-locked loop (PLL) can be implemented if the synthesizer is used with an external loop filter and voltage controlled oscillator (VCO). In addition, by programming R & N to 1, the part can be used as a stand alone PFD and charge pump.
