  Dynamic comparators are the core of high-speed, high-resolution
analog-to-digital converters (ADCs) used for communication applications. Most
of the dynamic comparators attain high-speed operation only for sufficiently
high input difference voltages. The comparator performance degrades at small
input difference voltages due to a limited pre-amplifier gain, which is
undesirable for high-speed, high-resolution ADCs. To overcome this drawback, a
cascode cross-coupled dynamic comparator is presented. The proposed comparator
improves the differential gain of the pre-amplifier and reduces the common-mode
voltage seen by the latch, which leads to a much faster regeneration at small
input difference voltages. The proposed comparator is designed, simulated, and
compared with the state-of-the-art techniques in 65 nm CMOS technology. The
results demonstrate that the proposed comparator achieves a delay of 46.5 ps at
1 mV input difference, and a supply of 1.1 V.
