Non-binary Successive Approximation Analog-to-Digital Converters: A Survey

Low-power successive-approximation (SA) analog-to-digital converters (ADCs) are attracting increasing attention these days in biomedical and sensor network applications. The binary search algorithm is one of the basic idea behind how they obtain a binary code representing an analog input. In practice, the imperfectness of analog circuit elements sometimes results in decision errors and decreases the resolution of A/D conversion. Thus, making accurate decisions using imperfect elements is a big challenge. This paper surveys one solution known as non-binary SA with redundancy as well as related topics and its application to state-of-the-art SA ADCs.