Abstract
Data weighted averaging (DWA) is the most popular Dynamic Element Matching (DEM) technique to reduce the effects of DAC nonlinearity in multi-bit Sigma-Delta Modulators (MBSDM). However, due to the non-symmetry of the unit-elements in multi-bit DAC, in-band signal-dependent tones always appear when a low oversampling ratio (OSR) is employed in traditional DWA. Therefore, a novel DEM technique, dual cycle shift DWA(DCSDWA), is proposed to deal with the tone problem in this paper. Compared with other modified DWAtechniques, DCSDWAis a more effective one with simple implementation. Using the proposed technique in a 4th-order MBSDM with an OSR of 32, the maximum in-band tone is reduced to 6 dB when a random DAC-element mismatching error of 0.5% is assumed. In addition, it results in a better linearity of signal-to-noise distortion ratio (SNDR) versus different input signal and a wider dynamic range (DR). The simulation results prove that the proposed DCSDWA is suitable for low OSR applications (OSR≥8) with a good performance.
Original language | English (US) |
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Title of host publication | 2009 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC 2009 |
Pages | 174-177 |
Number of pages | 4 |
DOIs | |
State | Published - Dec 1 2009 |
Event | 2009 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC 2009 - Xi'an, China Duration: Dec 25 2009 → Dec 27 2009 |
Other
Other | 2009 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC 2009 |
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Country/Territory | China |
City | Xi'an |
Period | 12/25/09 → 12/27/09 |
Keywords
- DAC nonlinearity
- Dual cycle shift DWA
- Multi-bit sigma-delta modulators