High speed – energy efficient successive approximation analog to digital converter using tri-level switching

This thesis reports issues and design methods used to achieve high-speed and high-resolution Successive Approximation Register analog to digital converters (SAR ADCs). A major drawback of this technique relates to the mismatch in the binary ratios of capacitors which causes nonlinearity. Another iss...

Full description

Saved in:
Bibliographic Details
Main Author: Sarafi, Sahar
Format: Thesis
Language:English
Published: 2015
Subjects:
Online Access:http://eprints.utm.my/id/eprint/77897/1/SaharSarafiPFKE2015.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-utm-ep.77897
record_format uketd_dc
spelling my-utm-ep.778972018-07-18T04:11:13Z High speed – energy efficient successive approximation analog to digital converter using tri-level switching 2015-11 Sarafi, Sahar TK Electrical engineering. Electronics Nuclear engineering This thesis reports issues and design methods used to achieve high-speed and high-resolution Successive Approximation Register analog to digital converters (SAR ADCs). A major drawback of this technique relates to the mismatch in the binary ratios of capacitors which causes nonlinearity. Another issue is the use of large capacitors due to nonlinear effect of parasitic capacitance. Nonlinear effect of capacitor mismatch is investigated in this thesis. Based on the analysis, a new Tri-level switching algorithm is proposed to reduce the matching requirement for capacitors in SAR ADCs. The integral non-linearity (INL) and the differential non-linearity (DNL) of the proposed scheme are reduced by factor of two over conventional SAR ADC, which is the lowest compared to the previously reported schemes. In addition, the switching energy of the proposed scheme is reduced by 98.02% compared with the conventional SAR architecture. A new correction method to solve metastability error of comparator based on a novel design approach is proposed which reduces the required settling time about 1.1τ for each conversion cycle. Based on the above proposed methods two SAR ADCs: an 8-bit SAR ADC with 50MS/sec sampling rate, and a 10-bit SAR split ADC with 70 MS/sec sampling rate have been designed in 0.18μm Silterra complementary metal oxide semiconductor (CMOS) technology process which works at 1.2V supply voltage and input voltage of 2.4Vp-p. The 8-bit ADC digitizes 25MHz input signal with 48.16dB signal to noise and distortion ratio (SNDR) and 52.41dB spurious free dynamic range (SFDR) while consuming about 589μW. The figure of merit (FOM) of this ADC is 56.65 fJ/conv-step. The post layout of the 10-bit ADC with 1MHz input frequency produces SNDR, SFDR and effective number of bits (ENOB) of 57.1dB, 64.05dB and 9.17Bit, respectively, while its DNL and INL are -0.9/+2.8 least significant bit (LSB) and -2.5/+2.7 LSB, respectively. The total power consumption, including digital, analog and reference power, is 1.6mW. The FOM is 71.75fJ/conv. step. 2015-11 Thesis http://eprints.utm.my/id/eprint/77897/ http://eprints.utm.my/id/eprint/77897/1/SaharSarafiPFKE2015.pdf application/pdf en public http://dms.library.utm.my:8080/vital/access/manager/Repository/vital:95147 phd doctoral Universiti Teknologi Malaysia, Faculty of Electrical Engineering Faculty of Electrical Engineering
institution Universiti Teknologi Malaysia
collection UTM Institutional Repository
language English
topic TK Electrical engineering
Electronics Nuclear engineering
spellingShingle TK Electrical engineering
Electronics Nuclear engineering
Sarafi, Sahar
High speed – energy efficient successive approximation analog to digital converter using tri-level switching
description This thesis reports issues and design methods used to achieve high-speed and high-resolution Successive Approximation Register analog to digital converters (SAR ADCs). A major drawback of this technique relates to the mismatch in the binary ratios of capacitors which causes nonlinearity. Another issue is the use of large capacitors due to nonlinear effect of parasitic capacitance. Nonlinear effect of capacitor mismatch is investigated in this thesis. Based on the analysis, a new Tri-level switching algorithm is proposed to reduce the matching requirement for capacitors in SAR ADCs. The integral non-linearity (INL) and the differential non-linearity (DNL) of the proposed scheme are reduced by factor of two over conventional SAR ADC, which is the lowest compared to the previously reported schemes. In addition, the switching energy of the proposed scheme is reduced by 98.02% compared with the conventional SAR architecture. A new correction method to solve metastability error of comparator based on a novel design approach is proposed which reduces the required settling time about 1.1τ for each conversion cycle. Based on the above proposed methods two SAR ADCs: an 8-bit SAR ADC with 50MS/sec sampling rate, and a 10-bit SAR split ADC with 70 MS/sec sampling rate have been designed in 0.18μm Silterra complementary metal oxide semiconductor (CMOS) technology process which works at 1.2V supply voltage and input voltage of 2.4Vp-p. The 8-bit ADC digitizes 25MHz input signal with 48.16dB signal to noise and distortion ratio (SNDR) and 52.41dB spurious free dynamic range (SFDR) while consuming about 589μW. The figure of merit (FOM) of this ADC is 56.65 fJ/conv-step. The post layout of the 10-bit ADC with 1MHz input frequency produces SNDR, SFDR and effective number of bits (ENOB) of 57.1dB, 64.05dB and 9.17Bit, respectively, while its DNL and INL are -0.9/+2.8 least significant bit (LSB) and -2.5/+2.7 LSB, respectively. The total power consumption, including digital, analog and reference power, is 1.6mW. The FOM is 71.75fJ/conv. step.
format Thesis
qualification_name Doctor of Philosophy (PhD.)
qualification_level Doctorate
author Sarafi, Sahar
author_facet Sarafi, Sahar
author_sort Sarafi, Sahar
title High speed – energy efficient successive approximation analog to digital converter using tri-level switching
title_short High speed – energy efficient successive approximation analog to digital converter using tri-level switching
title_full High speed – energy efficient successive approximation analog to digital converter using tri-level switching
title_fullStr High speed – energy efficient successive approximation analog to digital converter using tri-level switching
title_full_unstemmed High speed – energy efficient successive approximation analog to digital converter using tri-level switching
title_sort high speed – energy efficient successive approximation analog to digital converter using tri-level switching
granting_institution Universiti Teknologi Malaysia, Faculty of Electrical Engineering
granting_department Faculty of Electrical Engineering
publishDate 2015
url http://eprints.utm.my/id/eprint/77897/1/SaharSarafiPFKE2015.pdf
_version_ 1747817857851326464