Beyond Sole Parametric Optimization Design Regimes: Understanding and Advancing the Frontiers of High-Speed ADCs

Driven by relentless demands for expeditious data acquisition in modern communication systems, radar, and instrumentation, Nyquist analog-to-digital converters (ADCs) have emerged as critical components due to their ability to direct sample and digitize wideband signals at or near the Nyquist rate. Remarkable progress has been made in both sampling rates and energy efficiency in recent decades, thanks to advances in technology scaling, the composite of architecture, and circuit innovations. However, recent research trends often overemphasize a single parameter, such as the Figure of Merit (FoM), as the primary benchmark of the frontiers, obscuring the actual requirements and purposes of high-speed ADCs in the systems. This article focuses on high-speed Nyquist ADCs, discussing their background, fundamentals, challenges, and reviewing pronounced solutions. It aims to broaden the scope of engineering trends beyond the classic FoM-driven design philosophy.