A/D Converters

Our research in analog-to-digital converters (ADCs) focuses on different topics. Various types of Sigma-Delta modulators as well as high-resolution SAR ADCs are investigated.

For Sigma-Delta modulators, we cover the description and modeling of non-ideal behaviors. Moreover, the development of new design methodologies is at the center of interest. Both innovative architectures and improvement of established techniques are explored. Our work analyzes and designs Sigma-Delta modulators for wireless receivers as well as biomedical implants.

Furthermore, we develop new concepts for high resolution SAR ADCs. The research targets to advance the state-of-the-art with novel architectures that provide low power, low cost and at the same time highly efficient Nyquist rate ADCs.


High-Resolution, Efficient Incremental Sigma-Delta Modulators

M. Mokhtar, O. Ismail: Sigma-Delta (ΣΔ) ADCs are suitable for various applications, due to its oversampling and noise-shaping behavior, thus high resolutions can be achieved independent on the matching accuracy of the analog components. For multiplexed applications, where an ADC is used to digitize the input coming from multi-channels ... [more]

Online Tool for Rapid Continuous-Time ΣΔ Modulator Design

P. Kässer: ΣΔ A/D converters are the state of the art for many different applications. The basis for this type of A/D converter is the ΣΔ modulator. For a long time, discrete-time (DT) ΣΔ modulators dominated as their design techniques could easily be adopted to ensured high performance... [ more]

Ultra-low Power, Wide Bandwidth Continuous-time Sigma Delta Analog to Digital Converter Design

A. Abdelaal, M. Pietzko: Continues time delta sigma modulators (CTDS) have recently become the key device for broadband wireless and wireline communication.  Due to there built in anti-aliasing filter and the ability to have relaxed sampling requirements the CTDS modulators are preferred over there discrete time counterparts ... [more]