Design and measurement of a CT delta-sigma ADC with switched-capacitor switched-resistor feedback
(2009) In IEEE Journal of Solid-State Circuits 44(2). p.473-483- Abstract
- The performance of traditional continuous-time
(CT) delta-sigma analog-to-digital converters (ADCs) is
limited by their large sensitivity to feedback pulse-width variations
caused by clock jitter in their feedback digital-to-analog
converters (DACs). To mitigate that effect, we propose a modified
switched-capacitor (SC) feedback DAC technique, with a
variable switched series resistor (SR). The architecture has the
additional benefit of reducing the typically high SC DAC output
peak currents, resulting in reduced slew-rate requirements for the
loop-filter integrators. A theoretical investigation is carried out
which provides new insight into the... (More) - The performance of traditional continuous-time
(CT) delta-sigma analog-to-digital converters (ADCs) is
limited by their large sensitivity to feedback pulse-width variations
caused by clock jitter in their feedback digital-to-analog
converters (DACs). To mitigate that effect, we propose a modified
switched-capacitor (SC) feedback DAC technique, with a
variable switched series resistor (SR). The architecture has the
additional benefit of reducing the typically high SC DAC output
peak currents, resulting in reduced slew-rate requirements for the
loop-filter integrators. A theoretical investigation is carried out
which provides new insight into the synthesis of switched-capacitor
with switched series resistor (SCSR) DACs with a specified
reduction of the pulse-width jitter sensitivity and minimal power
consumption and complexity. To demonstrate the concept and to
verify the reduced pulse-width jitter sensitivity a 5 mW, 312 MHz,
second order, low-pass, 1-bit, CT delta-sigma modulator with SCSR
feedback was implemented in a 1.2 V, 90 nm, RF-CMOS process.
An SNR of 66.4 dB and an SNDR of 62.4 dB were measured
in a 1.92 MHz bandwidth. The sensitivity to wideband clock
phase noise was reduced by 30 dB compared to a traditional
switched-current (SI) return-to-zero (RZ) DAC. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1037990
- author
- Andersson, Martin LU and Sundström, Lars LU
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- clock jitter, delta-sigma modulation, A/D conversion
- in
- IEEE Journal of Solid-State Circuits
- volume
- 44
- issue
- 2
- pages
- 473 - 483
- publisher
- IEEE - Institute of Electrical and Electronics Engineers Inc.
- external identifiers
-
- wos:000263032100015
- scopus:59349110804
- ISSN
- 0018-9200
- DOI
- 10.1109/JSSC.2008.2010978
- language
- English
- LU publication?
- yes
- id
- fa759f02-c82b-4e3d-bbbf-e3587fcb2bba (old id 1037990)
- date added to LUP
- 2016-04-01 14:48:52
- date last changed
- 2025-04-04 14:47:47
@article{fa759f02-c82b-4e3d-bbbf-e3587fcb2bba,
abstract = {{The performance of traditional continuous-time<br/><br>
(CT) delta-sigma analog-to-digital converters (ADCs) is<br/><br>
limited by their large sensitivity to feedback pulse-width variations<br/><br>
caused by clock jitter in their feedback digital-to-analog<br/><br>
converters (DACs). To mitigate that effect, we propose a modified<br/><br>
switched-capacitor (SC) feedback DAC technique, with a<br/><br>
variable switched series resistor (SR). The architecture has the<br/><br>
additional benefit of reducing the typically high SC DAC output<br/><br>
peak currents, resulting in reduced slew-rate requirements for the<br/><br>
loop-filter integrators. A theoretical investigation is carried out<br/><br>
which provides new insight into the synthesis of switched-capacitor<br/><br>
with switched series resistor (SCSR) DACs with a specified<br/><br>
reduction of the pulse-width jitter sensitivity and minimal power<br/><br>
consumption and complexity. To demonstrate the concept and to<br/><br>
verify the reduced pulse-width jitter sensitivity a 5 mW, 312 MHz,<br/><br>
second order, low-pass, 1-bit, CT delta-sigma modulator with SCSR<br/><br>
feedback was implemented in a 1.2 V, 90 nm, RF-CMOS process.<br/><br>
An SNR of 66.4 dB and an SNDR of 62.4 dB were measured<br/><br>
in a 1.92 MHz bandwidth. The sensitivity to wideband clock<br/><br>
phase noise was reduced by 30 dB compared to a traditional<br/><br>
switched-current (SI) return-to-zero (RZ) DAC.}},
author = {{Andersson, Martin and Sundström, Lars}},
issn = {{0018-9200}},
keywords = {{clock jitter; delta-sigma modulation; A/D conversion}},
language = {{eng}},
number = {{2}},
pages = {{473--483}},
publisher = {{IEEE - Institute of Electrical and Electronics Engineers Inc.}},
series = {{IEEE Journal of Solid-State Circuits}},
title = {{Design and measurement of a CT delta-sigma ADC with switched-capacitor switched-resistor feedback}},
url = {{http://dx.doi.org/10.1109/JSSC.2008.2010978}},
doi = {{10.1109/JSSC.2008.2010978}},
volume = {{44}},
year = {{2009}},
}