Next-Generation Delta-Sigma Converters: Trends and Perspectives

This paper presents an overview of emerging circuits and systems techniques which are at the forefront of the state of the art in ΔΣ modulators, pushing their performance forward and giving rise to new generations of data converters. Among others, those strategies involving the development of new applications and paradigms-like RF/GHz-range ΔΣ digitisation, digital-assisted embedded loop filters, time-to-digital conversion and hybrid ΔΣ/Nyquist-rate architectures-are discussed, as well as the implications and design challenges derived from their integration in deep nanometer CMOS technologies. The envisioned ΔΣ techniques are presented in a systematic way around the main analog building blocks embedded in a ΔΣ modulator, i.e., the loop filter and the quantizer. Analysing the trends in the design of these blocks allows us to offer perspectives on how ΔΣ converters will evolve in the next years.