Institute of Microelectronics

Low Power, Wide Bandwidth Continuous-Time Delta-Sigma Analog to Digital Converters with High Internal Resolution

Continuous-time delta sigma modulators (CT-DSMs) have recently become the key device for broadband wireless and wireline communication. Due to their built in anti-aliasing filter and the ability to have relaxed sampling requirements the CTDS modulators are preferred over their discrete-time counterparts.

A 2.4GS/s Continuous-time Delta Sigma Modulator
A 2.4GS/s Continuous-time Delta Sigma Modulator

This project focuses on designing, developing and testing very high speed, wide bandwidth, low power Delta-Sigma ADCs. One of the key points to reach this goal is the focus on a high-resolution internal quantizer. In combination with a low oversampling ratio this allows to achieve a wide bandwidth, while power consumption remains low due to the limited sampling speed. Applying special compensation techniques ensures stability of the CT-DSM and opens a feasible way to further increase the conversion rates while keeping the FoM below 100fJ/conversion.

Publications

4. Pietzko, M.; Ungethüm, J.; Abdelaal, A.; Kauffman, J. G.; Ortmanns, M.
A 600MS/s 10-bit SAR ADC with unit via-based delta-length C-DAC in 22nm FDSOI
IEEE International Symposium on Circuits and Systems (ISCAS), Singapore
Mai 2024
DOI: 10.1109/ISCAS58744.2024.10558087

3. Pietzko, M.; Spiess, J.; Ungethüm, J.; Kauffman, J. G.; Li, Q.; Ortmanns, M.
Bitwise ELD Compensation under Integrator Nonidealities in ΔΣ Modulators
21st IEEE Interregional NEWCAS Conference (NEWCAS), Edinburgh, United Kingdom
Juni 2023
DOI: 10.1109/NEWCAS57931.2023.10198050

2. Pietzko, M.; Ungethüm, J.; Kauffman, J. G.; Ortmanns, M.
Delay Error Shaping in ΔΣ Modulators Using Time-Interleaved High Resolution Quantizers
IEEE Transactions on Circuits and Systems I: Regular Papers
Mai 2023
DOI: 10.1109/TCSI.2023.3269573

1. Pietzko, M.; Ungethüm, J.; Kauffman, J. G.; Li, Q.; Ortmanns, M.
Bitwise ELD Compensation in ∆Σ Modulators
IEEE International Symposium on Circuits and Systems (ISCAS), Austin, USA
Mai 2022
DOI: 10.1109/ISCAS48785.2022.9937305

Funding

This project is funded by the German Research Foundation (DFG) under grant number OR 245/17-2.