Continuous-Time Pipelined ADC: A Breed of Continuous-Time ADCs for Wideband Data Conversion
Hajime Shibata
Abstract
The continuous-time (CT) pipelined analog-to-digital converter (ADC) is an emerging ADC architecture suitable for wide- bandwidth (BW) digitization in fully integrated receiver applications. It inherits the integration-friendly features of CT <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta \Sigma $ </tex-math></inline-formula> ADCs, such as inherent anti-aliasing, while achieving the wide- BW operation originating from discrete-time (DT) pipelined ADCs. In this review article, we introduce a gain-centric ADC model and apply the key criteria derived from the model to transform a DT pipelined ADC into a CT pipelined ADC. We then discuss the design considerations and essential building blocks of the CT pipelined ADC. Finally, we examine several implementations of this architecture with their highlights and challenges.