Observations concerning "horn Spurs" in a MASH-based Fractional-N CP-PLL
Abstract
A fractional-N Charge Pump (CP) PLL with a Multi-stAge noise SHaping (MASH) 1-1-1 divider controller has been reported in simulation to exhibit pairs of spurious tones called 'horn spurs, ' the locations of which depend on the initial condition of the modulator. This paper presents simulations, empirical analysis and experimental measurements which confirm the robustness of the phenomenon. Matlab simulation results are presented for a type-II CP-PLL with a third order MASH Digital ΔΣ Modulator (DDSM). Measurements are presented for a commercial monolithic wideband synthesizer, the ADF4356.
Publication Title
2019 26th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2019
Recommended Citation
Mazzaro, V., & Kennedy, M. (2019). Observations concerning "horn Spurs" in a MASH-based Fractional-N CP-PLL. 2019 26th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2019, 17-20. https://doi.org/10.1109/ICECS46596.2019.8964903
