@Article{cmc.2020.011701,
AUTHOR = {Liangbo Xie, Sheng Li, Yan Ren, Zhengwen Huang},
TITLE = {A Two-Dimension Time-Domain Comparator for Low Power SAR  ADCs},
JOURNAL = {Computers, Materials \& Continua},
VOLUME = {65},
YEAR = {2020},
NUMBER = {2},
PAGES = {1519--1529},
URL = {http://www.techscience.com/cmc/v65n2/39891},
ISSN = {1546-2226},
ABSTRACT = {This paper presents a two-dimension time-domain comparator suitable for low 
power successive-approximation register (SAR) analog-to-digital converters (ADCs). The 
proposed two-dimension time-domain comparator consists of a ring oscillator collapsebased comparator and a counter. The propagation delay of a voltage controlled ring 
oscillator depends on the input. Thus, the comparator can automatically change the 
comparison time according to its input difference, which can adjust the power consumption 
of the comparator dynamically without any control logic. And a counter is utilized to count 
the cycle needed to finish a comparison when the input difference is small. Thus, the 
proposed comparator can not only provide the polarity of the input, but also the amount 
information of the input, which helps to skip most of the SAR cycles when the initial input 
is small. Thus, most energy can be saved when the initial input is small. The proposed timedomain comparator is designed in 0.18 μm CMOS technology. Simulation results 
demonstrate that the comparator can not only save power consumption, but also give the 
design flexibility, and the current is only nA level when the supply voltage is 0.6 V.},
DOI = {10.32604/cmc.2020.011701}
}