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Author Suarez, G. ♦ Jimenez, M. ♦ Fernandez, F.O.
Sponsorship IEEE Circuits and Systems Society
Source IEEE Xplore Digital Library
Content type Text
Publisher Institute of Electrical and Electronics Engineers, Inc. (IEEE)
File Format PDF
Copyright Year ©2004
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Physics ♦ Electricity & electronics
Subject Keyword Mathematical model ♦ Delta-sigma modulation ♦ Digital modulation ♦ Analog-digital conversion ♦ Digital-analog conversion ♦ Computational modeling ♦ Transient response ♦ Transconductance ♦ Admittance ♦ Jitter ♦ VHDL-AMS SDM ♦ Behavioral modeling ♦ switched-capacitor (SC) integrator ♦ sigma–delta modulator ( $\Sigma \Delta{\rm Ms}$) ♦ Simulink SDM ♦ SC integrator
Abstract Sigma-delta Modulators (SigmaDeltaMs) are cornerstone elements in oversampled analog-to-digital converters and digital-to-analog converters (DAC). Although transistor-level simulation is the most accurate approach known for these components, this method becomes impractical for complex systems due to its long computational time requirements. Behavioral modeling has become a viable solution to this problem. In this paper, we study styles and issues in the accurate modeling of low-power, high-speed SigmaDeltaMs and introduce two new behavioral models for switched-capacitor (SC) integrators. The first model is based on the SC integrator transient response, including the effects of the amplifier transconductance, output conductance, and the dynamic capacitive loading effect on the settling time. The second model is based on a symbolic node admittance matrix representation of the system. Nonidealities such as jitter, thermal noise, and DAC mismatch are also addressed and included in a dual-band, GSM/WCDMA, second-order, multibit SigmaDeltaM model with individual level averaging. VHDL-AMS and MATLAB Simulink were used as modeling languages. Both models are validated against experimental data, showing competitive results in the signal-to-noise-plus-distortion ratio. A comparative analysis between the proposed and a traditional model is presented, with emphasis on the degrading effects due to the integrator dynamics. Moreover, a general simulation speed analysis of the proposed models is addressed.
Description Author affiliation :: NASA Goddard Space Flight Center, Greenbelt
ISSN 15498328
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2007-06-01
Publisher Place U.S.A.
Rights Holder Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Volume Number 54
Issue Number 6
Size (in Bytes) 1.10 MB
Page Count 9
Starting Page 1236
Ending Page 1244

Source: IEEE Xplore Digital Library