Sigma-delta modulator with spectrally shaped feedback
This paper explores the use of finite-impulse response (FIR) filters in the feedback path of a low-pass sigma-delta modulator in order to combat some nonideal effects encountered in an analog implementation. In this approach, the filter corresponding to the first integrator is a lowpass filter which...
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Published in | IEEE transactions on circuits and systems. 2, Analog and digital signal processing Vol. 50; no. 9; pp. 518 - 530 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
New York
IEEE
01.09.2003
The Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
Subjects | |
Online Access | Get full text |
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Summary: | This paper explores the use of finite-impulse response (FIR) filters in the feedback path of a low-pass sigma-delta modulator in order to combat some nonideal effects encountered in an analog implementation. In this approach, the filter corresponding to the first integrator is a lowpass filter which smoothes out the feedback waveform by attenuating the high-frequency quantization noise. This lowpass filtering decreases the power consumption of a switched-capacitor implementation and alternatively reduces the sensitivity to clock jitter in a continuous-time structure. A design methodology ensuring the stability of the system is presented. Theoretical analysis and simulations show that the FIR filters allow a continuous-time single-bit modulator to achieve the jitter performance of a comparable multibit modulator. |
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ISSN: | 1057-7130 1558-125X |
DOI: | 10.1109/TCSII.2003.815023 |