Event-Based ADCs vs. Nyquist ADCs: Rethinking Performance Metrics

Event-based analog-to-digital converters (ADCs) are an interesting alternative to conventional Nyquist ADCs. However, their application is far from mainstream. One reason for this lack of industry adoption might be the absence of a universal performance metric for event-based ADCs that can be used robustly to compare them with Nyquist ADCs. This article addresses this gap by summarizing key theoretical concepts and highlighting primary distinctions between event-based ADCs and Nyquist ADCs. The theoretical findings are substantiated by the measurement results of a demonstrator implemented at the PCB level. Building on these insights, the work demonstrates that the conventional figures of merit (FoMs) used for Nyquist ADCs are inadequate to evaluate event-based ADCs, prompting the development of a new and tailored performance metric. Finally, the performance of state of the art integrated event-based ADCs is evaluated using the proposed FoM.