Digital Approaches to ISI-Mitigation in High-Resolution Oversampled Multi-Level D/A Converters
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Date
2011
Journal Title
Journal ISSN
Volume Title
Publisher
Ieee-inst Electrical Electronics Engineers inc
Abstract
A new digital signal processing approach to shaping intersymbol interference (ISI) and static mismatch errors simultaneously in oversampled multi-level digital to analog converters (DAC) has recently been proposed. In this paper, a mathematical framework is established for analyzing ISI errors as well as comparing the ISI sensitivities of different mismatch shaping algorithms. The framework is used to analyze the fundamental problems of popularly used algorithms such as data-weighted-averaging (DWA) in the presence of nonlinear ISI: Large-signal even-order distortion and frequency modulated harmonics at low signal levels. The new ISI-shaping algorithm results in significant improvement over previous schemes including the modified Mismatch Shaper (MMS) which also addresses ISI error. The new ISI shaper, while increasing the digital complexity, practically eliminates the need for conventional ISI mitigation techniques such as time consuming, layout-critical, non-automated and process specific analog design methods. The advantages of ISI shaping is further verified on an experimental audio DAC with simple non-return-to-zero (NRZ) current steering segments implemented in a 45 nm CMOS process and running off a single-phase clock of only 3.072 MHz.
Description
KELLECI, BURAK/0000-0002-0961-1153
Keywords
Audio, current-steering DAC, DAC, data-weighted averaging, digital-to-analog conversion, dynamic element matching, frequency modulation, idle tones, intersymbol-interference (ISI), ISI-shaping, mismatch shaping, noise shaping, non-return-to-zero (NRZ), out-of-band noise, sigma-delta modulation, vector quantizer
Turkish CoHE Thesis Center URL
Citation
51
WoS Q
Q1
Scopus Q
Q1
Source
IEEE International Solid-State Circuits Conference (ISSCC) -- FEB 20-24, 2011 -- San Francisco, CA
Volume
46
Issue
12
Start Page
2892
End Page
2903