A Review of Improved CMOS Dynamic Comparators

This paper reviews some CMOS dynamic comparators that achieving high performances on different features. Based on conventional structures, a comparator with a dynamic floating inverter amplifier optimize their circuit by a floating reservoir capacitor, which achieves the best energy efficiency while is insensitive to common-mode voltage. The optimization of the Elzakker's comparators increases the pre-amplifier stage's structures by adding a tail capacitor and a tail transistor. And three-stage comparator with extra parallel feedback is discussed, decreasing delay significantly. The classic comparator comprises a differential input stage, two regenerative flip-flops, and an S-R latch is also mentioned.