Calculation of sequence lengths in MASH 1-1-1 digital delta sigma modulators with a constant input
Abstract
Knowledge of exact sequence lengths of undithered Digital Delta Sigma Modulators (DDSM) with respect to the input, initial conditions, and quantizer modulus, enables designers to predict spur intervals. It is necessary to know the sequence length for some applications such as fractional-N frequency synthesizers [2]. In this paper, sequence lengths of Multi stAge noise SHaping (MASH) DDSMs comprising first order Error Feedback Modulators (EFM) up to three stages are calculated. Exact formulae for calculating sequence lengths with all possible inputs, initial conditions and moduli are provided for first and second order modulators. In the case of a third order modulator, the sequence length is found for the special case when it is not divisible by 3 but it is divisible by 4. © 2007 IEEE.
Publication Title
Proceedings of the 2007 Ph.D Research in Microelectronics and Electronics conference, PRIME 2007
Recommended Citation
Hosseini, K., Kennedy, M., & McCarthy, C. (2007). Calculation of sequence lengths in MASH 1-1-1 digital delta sigma modulators with a constant input. Proceedings of the 2007 Ph.D Research in Microelectronics and Electronics conference, PRIME 2007, 13-16. https://doi.org/10.1109/RME.2007.4401799
