Print Email Facebook Twitter A Chopper-Stabilized Amplifier with a Relaxed Fill-In Technique and 22.6pA Input Current Title A Chopper-Stabilized Amplifier with a Relaxed Fill-In Technique and 22.6pA Input Current Author Rooijers, C.T. (TU Delft Electronic Instrumentation) Huijsing, J.H. (TU Delft Electronic Instrumentation) Makinwa, K.A.A. (TU Delft Microelectronics) Department Microelectronics Date 2023 Abstract In chopper amplifiers, the interaction between the input signal and the chopper clock can cause intermodulation distortion (IMD). This is mainly due to finite amplifier bandwidth, which causes signal-dependent output spikes at the chopping transitions. Such chopper-induced IMD can be mitigated by the fill-in technique, which involves ping-ponging between the outputs of two identical OTAs chopped in quadrature, thus generating a spike-free output. In this letter, a relaxed implementation is proposed in which the output of a fill-in OTA is only briefly used to avoid the spikes of a chopped main OTA. As a result, the fill-in OTA does not need to be chopped, and so it can be duty-cycled to save power. Furthermore, the chopper ripple caused by the main OTA can now be suppressed by a single low-noise ripple-reduction loop, rather than the two AZ loops required in a previous ping-pong implementation of the fill-in technique. Compared to the latter, the proposed amplifier achieves similar IMD performance (-125.7 dB), a 25× lower input current (22.6 pA), and a flat noise floor (12 nV/ Hz). Subject Choppers (circuits)duty-cycled OTAintermodulation distortion (IMD)relaxed fill-in technique To reference this document use: http://resolver.tudelft.nl/uuid:090a83f9-9607-4b6d-8263-295a72dcb9ad DOI https://doi.org/10.1109/LSSC.2023.3286779 Embargo date 2023-12-15 ISSN 2573-9603 Source IEEE Solid State Circuits Letters, 6, 165 - 168 Bibliographical note Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2023 C.T. Rooijers, J.H. Huijsing, K.A.A. Makinwa Files PDF A_Chopper_Stabilized_Ampl ... urrent.pdf 2.56 MB Close viewer /islandora/object/uuid:090a83f9-9607-4b6d-8263-295a72dcb9ad/datastream/OBJ/view