Time-interleaved oversampling A/D converters: theory and practice

In this paper, the design procedure and practical issues regarding the realization of time-interleaved oversampling converters are presented. Using the concept of block digital filtering, it is shown that arbitrary ΔΣ topologies can be converted into corresponding time-interleaved structures. Practical issues such as finite opamp gain, mismatching, and DC offsets are addressed, analyzed, and practical solutions to overcome some of these problems are discussed. To verify the theoretical results, a discrete-component prototype of a second-order time-interleaved ΔΣ analog/digital (A/D) converter has been implemented and the design details as well as experimental results are presented