Título
Efficient dithering in MASH sigma-delta modulators for fractional frequency synthesizers
Autor
VICTOR RODOLFO GONZALEZ DIAZ
MIGUEL ANGEL GARCIA ANDRADE
GUILLERMO ESPINOSA FLORES VERDAD
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
The digital multistage-noise-shaping (MASH) ΣΔ modulators used in fractional frequency synthesizers are prone to spur tone generation in their output spectrum. In this paper, the state of the art on spur-tone-magnitude reduction is used to demonstrate that an M -bit MASH architecture dithered by a simple M -bit linear feedback shift register (LFSR) can be as effective as more sophisticated topologies if the dither signal is properly added. A comparison between the existent digital ΣΔ modulators used in fractional synthesizers is presented to demonstrate that the MASH architecture has the best tradeoff between complexity and quantization noise shaping, but they present spur tones. The objective of this paper was to significantly decrease the area of the circuit used to reduce the spur tone magnitude for these MASH topologies. The analysis is validated with a theoretical study of the paths where the dither signal can be added. Experimental results of a digital M -bit MASH 1-1-1 ΣΔ modulator with the proposed way to add the LFSR dither are presented to make a hardware comparison.
Editor
IEEE
Fecha de publicación
2010
Tipo de publicación
Artículo
Versión de la publicación
Versión aceptada
Recurso de información
Formato
application/pdf
Idioma
Inglés
Audiencia
Estudiantes
Investigadores
Público en general
Sugerencia de citación
Gonzalez-Diaz, V.R., et al., (2010). Efficient dithering in MASH sigma-delta modulators for fractional frequency synthesizers, IEEE Transactions on Circuits and Systems I: Regular Papers, Vol. 5, (9): 2394-2403
Repositorio Orígen
Repositorio Institucional del INAOE
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