An Analysis of CMOS Latched Comparators

Using suitable types of CMOS latched comparators for specific conditions is vital –because each comparator has different pros and cons. Also, it is important to determine which comparators to utilize for specific conditions. A need remains for the practical comparison of various types of comparators with applicable criteria. Within the present study, we performed comparisons between StrongArm latch, modified double-tail latch, and track-and-regenerate slicer with three different types of criteria. We analyzed each comparator by controlling three types of variables: power supply, input common mode voltage, and differential signal input. Then, in keeping with these three types of criteria, the simulation results, kickback noise, power consumption, and clock-to-Q delay were evaluated. We designed three kinds of CMOS latched comparators with 40-nm CMOS technology. In post-layout simulations, using a StrongArm latch resulted in low power consumption. Modified double-tail latch showed strength in kickback noise and is applicable for low power supply. Track-and-regenerate slicer showed better performance in clock-to-Q delay. Our findings expand on the performance of each comparator that would be applied to mixed-signal circuits and systems.