Title
An Adaptive Dac Settling Waiting Time Optimized Ultra Low Voltage Asynchronous Sar Adc In 40 Nm Cmos
Abstract
An ultra low power and low voltage successive-approximation-register (SAR) analog-to-digital converter (ADC) with timing optimized asynchronous clock generator is presented. By calibrating the delay amount of the clock generator, the DAC settling waiting time is adaptively optimized to counter the device mismatch. This technique improved the maximum sampling frequency by 40% keeping ENOB around 7-bit at 0.4 V analog and 0.7 V digital power supply voltage. The delay time dependency on power supply has small effect to the accuracy of conversion. Decreasing of supply voltage by 9% degrades ENOB only by 0.1-bit, and the proposed calibration can give delay margins for high voltage swing. The prototype ADC fabricated in 40 nm CMOS process achieved figure of merit (FoM) of 8.75-fJ/conversion-step with 2.048 MS/s at 0.6 V analog and 0.7 V digital power supply voltage. The ADC can operates from 50 S/s to 8 MS/s keeping ENOB over 7.5-bit.
Year
DOI
Venue
2013
10.1587/transele.E96.C.820
IEICE TRANSACTIONS ON ELECTRONICS
Keywords
Field
DocType
ADC, SAR, ultra low power, asynchronous
Settling,Asynchronous communication,CMOS,Electronic engineering,Low voltage,Successive approximation ADC,Engineering
Journal
Volume
Issue
ISSN
E96C
6
1745-1353
Citations 
PageRank 
References 
1
0.41
9
Authors
5
Name
Order
Citations
PageRank
Ryota Sekimoto1779.08
Akira Shikata2779.08
Kentaro Yoshioka3549.04
Tadahiro Kuroda4659213.23
Hiroki Ishikuro528552.15