ADF4106,pdf datasheet (PLL Fre

The ADF4106 frequency synthesizer can be 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, programmable A counter and B counter, and a dual-modulus prescaler (P/P + 1). The A (6-bit) counter and B (13-bit) counter, in conjunction with the dual-modulus prescaler (P/P + 1), implement an N divider (N = BP + A). In addition, 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). Its very high bandwidth means that frequency doublers can be eliminated in many high frequency systems, simplifying system architecture and reducing cost.