NDLI: Automatic tuning of digitally-controllable positive-feedback OTAs in continuous-time sigma

Content Provider	Springer Nature Link
Author	Irfansyah, Astria Nur Nicholson, Andrew Peter Iberzav, Artemij Jenkins, Julian Lehmann, Torsten Hamilton, Tara Julia
Copyright Year	2016
Abstract	This paper proposes a technique suitable for on-chip tuning of digitally-tunable positive-feedback operational transconductor amplifiers in a continuous-time sigma–delta modulator (CT-SDM) with active-RC integrator stages. The work we present relies on phase shift and offset measurement of individual active-RC integrator stages output using comparators to estimate output conductance, DC-gain, and common mode level of the differential output signals. The tuning methodology aims to tune the integrator stages to achieve sufficient DC-gain as required by the SDM. We present experimental results to confirm the correlation of our integrator phase and output offset detection technique with the operational transconductance amplifier (OTA) DC gain. We employ this technique in a tuning process of two digitally-tunable OTA chips implemented in complementary metal-oxide semiconductor 180 nm process configured in a second-order CT-SDM circuit with discrete components. The tuning algorithm results in a measured signal-to-noise and distortion ratio (SNDR) of 46.97 dB, which is close to the maximum SNDR of 47.83 dB achievable across a subset of the digitally-tunable OTA code space. High-speed operation of the CT-SDM and tuning circuitry has been verified through circuit simulations.
Starting Page	469
Ending Page	483
Page Count	15
File Format	PDF
ISSN	09251030
Journal	Analog Integrated Circuits and Signal Processing
Volume Number	89
Issue Number	2
e-ISSN	15731979
Language	English
Publisher	Springer US
Publisher Date	2016-07-30
Publisher Place	New York
Access Restriction	One Nation One Subscription (ONOS)
Subject Keyword	Digital tuning Positive feedback Operational transconductance amplifier Continuous-time sigma–delta modulator Circuits and Systems Electrical Engineering Signal,Image and Speech Processing
Content Type	Text
Resource Type	Article
Subject	Surfaces, Coatings and Films Signal Processing Hardware and Architecture

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

A 89-dB DR 457-μW 20-kHz bandwidth delta-sigma modulator with gain-boosting OTAs

A 0.5-V 81.2 dB SNDR audio-band continuous-time Delta-Sigma modulator with SCR feedback

A low-power 2nd-order CT delta-sigma modulator with a single operational amplifier

An NTF-enhanced time-based continuous-time sigma-delta modulator

A 0.5-V 90-dB SNDR 102 dB-SFDR audio-band continuous-time delta–sigma modulator

Digital based calibration technique for continuous-time bandpass sigma-delta analog-to-digital converters

A low-power 2nd-order CT delta–sigma modulator with an asynchronous SAR quantizer

A 0.6-V 540-nW delta-sigma modulator for biomedical sensors

A clock jitter error compensation and auto-tuning structure for continuous-time $$\Upsigma\Updelta$$ modulators

Automatic tuning of digitally-controllable positive-feedback OTAs in continuous-time sigma–delta modulators

Similar Documents

A 89-dB DR 457-μW 20-kHz bandwidth delta-sigma modulator with gain-boosting OTAs

A 0.5-V 81.2 dB SNDR audio-band continuous-time Delta-Sigma modulator with SCR feedback

A low-power 2nd-order CT delta-sigma modulator with a single operational amplifier

An NTF-enhanced time-based continuous-time sigma-delta modulator

A 0.5-V 90-dB SNDR 102 dB-SFDR audio-band continuous-time delta–sigma modulator

Digital based calibration technique for continuous-time bandpass sigma-delta analog-to-digital converters

A low-power 2nd-order CT delta–sigma modulator with an asynchronous SAR quantizer

A 0.6-V 540-nW delta-sigma modulator for biomedical sensors

A clock jitter error compensation and auto-tuning structure for continuous-time $$\Upsigma\Updelta$$ modulators

Automatic tuning of digitally-controllable positive-feedback OTAs in continuous-time sigma–delta modulators