Name
Title | ||
|---|---|---|
A 0.9-V DAC-Calibration-Free Continuous-Time Incremental Delta–Sigma Modulator Achieving 97-dB SFDR at 2 MS/s in 28-nm CMOS |
Abstract | ||
|---|---|---|
This article shows the design of a wideband 3-0 sturdy-multi-stage noise-shaping (SMASH) continuous-time (CT) incremental delta–sigma (I-
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) analog-to-digital converter (ADC). The two stages’ quantizers (QTZs) are implemented by a single re-configurable multibit (MB) asynchronous (A)SAR ADC. The digital-to-analog converter (DAC) nonlinearities are suppressed by reconfiguring the asynchronous successive-approximation register (ASAR) ADC from 2 to 5 b, and correspondingly, the DACs dynamically switch from 1.5- to 4-b tri-level outputs within each Nyquist conversion cycle. This results in a DAC-calibration-free MB operation. A two-tap FIR filter is implemented in the feedback DACs to reduce jitter requirements in the initial 1.5-b cycles. Through the design representation, a detailed fundamental comparison between an X-0 SMASH architecture and an X-order single-loop modulator is discussed. This discussion highlights the introduction of an efficient tri-level combination between the MSB and the LSBs of the ASAR QTZ. The resulting SMASH CT I-
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modulator was fabricated in 28-nm CMOS technology with an active area of 0.125 mm2. It achieves 97-dB spurious-free dynamic range (SFDR) without calibration, 89-dB dynamic range (DR), and 81.2-dB SNDR in a 1-MHz bandwidth (BW). It consumes 3.6 mW from a single 0.9-V supply. The design shows very good robustness across different tested samples, supply variations, and across temperatures from −20 °C to 80 °C. |
Year | DOI | Venue |
|---|---|---|
2022 | 10.1109/JSSC.2022.3160325 | IEEE Journal of Solid-State Circuits |
Keywords | DocType | Volume |
Asynchronous successive-approximation register (ASAR) quantizer (QTZ),continuous time (CT),delta–sigma modulator,incremental,sturdy-multi-stage noise-shaping (SMASH),tri-level digital-to-analog converter (DAC) | Journal | 57 |
Issue | ISSN | Citations |
11 | 0018-9200 | 0 |
PageRank | References | Authors |
0.34 | 27 | 6 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Mohamed A. Mokhtar | 1 | 1 | 2.38 |
| Ahmed Abdelaal | 2 | 0 | 0.34 |
| Markus Sporer | 3 | 0 | 0.34 |
| Joachim Becker | 4 | 1 | 1.02 |
| John G. Kauffman | 5 | 1 | 1.02 |
| Maurits Ortmanns | 6 | 501 | 114.46 |