Non-Linear-Error Correction in Fractional-N Digital PLL Frequency Synthesizer

摘要

The present disclosure relates to a frequency synthesizer. The frequency synthesizer includes a phase comparator having first and second input nodes. The first input node receives a reference signal having a reference frequency. A channel control block has an input that receives a channel word and an output coupled to the second input node of the phase comparator. A local oscillator (LO) output node provides an LO signal having an LO frequency based on the reference frequency and the channel word. A feedback back couples the LO output node to the second input node of the phase comparator through the channel control block. A non-linear error correction element is operably coupled on a coupling path extending between the phase comparator and the DCO.