资 源 简 介
The ADF411x family of frequency synthesizers can be used to implement local oscillators (LO) in the upconversion and downconversion secTIons of wireless receivers and transmitters. They consist of a low noise digital phase frequency detector (PFD), a precision charge pump, a programmable reference divider, programmable A and B counters, and a dual-modulus prescaler (P/P + 1). The A (5-bit) and B (13-bit) counters, 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).
