Wideband and Low-Power Delta-Sigma ADCs: State of the Art, Trends and Implementation Examples
Maurits Ortmanns
Abstract
Continuous-time Delta-Sigma (ΔΣ) ADCs have obtained a dominant position for the digitization in wireless receivers. With steadily improved theoretical understanding, architectural innovations and excellent circuit designs, they have achieved bandwidths of hundreds of MHz, while showing high resolution with highly competetive power efficiency. Moreover, due to their filtering properties, CT ΔΣ modulators are highly attractive for hostile receiver environments. In this review, the background and recent architectural and circuit innovations will be highlighted, including an exceeding number of hybrid designs, which improved both the application scenario as well as the power efficiency of this class of ADC. State-of-the-art examples will be illustrated and open research topics discussed.