Asynchronous ADCs: Design Methodology and Case study

International audienceWe present a new class of Analog-to-Digital Converters (ADCs), based on an irregular sampling of the analog signal, and an asynchronous design. Because these ADCs are not conventional, a design methodology is also presented. It determines their characteristics given the required Effective Number of Bits and the properties of the analog signal to convert. A prototype has been designed for speech applications, using the 0.18-µm CMOS technology from STMicroelectronics. Electrical simulations prove that the Figure of Merit (FoM) is increased by more than one order of magnitude compared to synchronous Nyquist ADCs