Multibit Sturdy MASH xcex94xcexa3 Modulator with Errorshaped Segmented DACs for Wideband Lowpower Applications This paper presents several techniques to enhance the resolution of sturdy multistage noise shaping (MASH) xcex94xcexa3 modulator (DSM). The proposed structure significantly suppresses the quantization noise (QN) by employing a highresolution quantizer with a segmented MSBLSB DAC feedback in the first loop as well as noise coupling techniques in both loops. Reducing QN of the first loop significantly decreases the output swings of the integrators, thus improving the stability of the first loop. Besides, the construction of one extra order shaping function mitigates the leakage of coarse QN introduced by a gain mismatch between MSB and LSB DACs of the highresolution quantizer. Simulation results demonstrate the effectiveness of the proposed architecture to achieve high resolution while employing lowgain opamps for all integrators.

FIR Feedback in Continuous Time Incremental SigmaDelta ADCs In this paper, we present a new method to include finiteimpulseresponse (FIR) feedback digitaltoanalog converters (DACs) in continuoustime (CT) Incremental SigmaDelta (Ixcexa3xcex94) analogtodigital converters (ADC), which minimizes transient overshoots and thereby maximizes the modulatoru0027s stability. More specifically, it can be shown that increasing the number of FIR taps in Ixcexa3xcex94 feedback DACs could lead to instability or a reduced maximum stable amplitude (MSA), even when using a proper compensation path. However, by presetting the FIR feedback to a voltage close to the input signal, a larger number of FIR taps can be used, increasing the jitter robustness of the CT Ixcexa3xcex94. This presetting is achieved using a low resolution Nyquist rate ADC to preset the FIR taps. Moreover, presetting the FIR feedback slightly increases the modulatoru0027s MSA and signaltonoise ratio compared to a nonreturntozero (NRZ) feedback. To validate the proposed presetting approach, a thirdorder Ixcexa3xcex94ADC employing a 12tap FIR DAC with presetting using a 4bit flash ADC is compared against a conventional NRZ DAC and a conventional FIR DAC without presetting in MATLABSimulink.