Print Email Facebook Twitter A chopper current-feedback instrumentation amplifier with a 1 mHz 1/f noise corner and an AC-coupled ripple reduction loop Title A chopper current-feedback instrumentation amplifier with a 1 mHz 1/f noise corner and an AC-coupled ripple reduction loop Author Wu, R. Makinwa, K.A.A. Huijsing, J.H. Faculty Electrical Engineering, Mathematics and Computer Science Department Microelectronics & Computer Engineering Date 2009-12-15 Abstract This paper presents a chopper instrumentation amplifier for interfacing precision thermistor bridges. For high CMRR and DC gain, the amplifier employs a three-stage current-feedback topology with nested-Miller compensation. By chopping both the input and intermediate stages of the amplifier, a 1 mHz 1/f noise corner was achieved at an input-referred noise power spectral density (PSD) of 15 nV/¿Hz. To reduce chopper ripple, the amplifier employs a continuous-time AC-coupled ripple reduction loop. Due to its continuous-time nature, the loop causes no noise folding to DC and hence offers improved noise performance over auto-zeroed amplifiers. The loop reduces chopper ripple by more than 60 dB, to levels below the amplifier's own input-referred noise. Furthermore, a maximum input referred offset of 5 µ V and a CMRR greater than 120 dB were measured at a supply current of 230 µA at 5 V. Subject choppingcontinuous-timecurrent-feedbacknoise efficiency factor (NEF)noise foldingoffset1/f noiseripple reductionthermistor To reference this document use: http://resolver.tudelft.nl/uuid:f9743b10-a375-4425-bb28-d96d843e52f7 DOI https://doi.org/10.1109/JSSC.2009.2032710 Publisher IEEE ISSN 0018-9200 Source IEEE Journal of Solid-State Circuits, 44 (12), 2009 Part of collection Institutional Repository Document type journal article Rights (c) 2009 Wu, R.; Makinwa, K.A.A.; Huijsing, J.H.; IEEE Files PDF rong2009.pdf 1.67 MB Close viewer /islandora/object/uuid:f9743b10-a375-4425-bb28-d96d843e52f7/datastream/OBJ/view