Enhancing Performance of Ultra-Low Voltage Body-Driven Comparators through Clocked Supply Voltage

In this work, a novel technique to feed body-driven ultra-low voltage (ULV) comparators is investigated to enhance performance in terms of noise and offset. The technique, which consists in clocking the supply voltage of the latch devices, causes the output common mode voltage to experience a positive step at the beginning of the evaluation phase. As a result, the preamplification gain is enhanced because the output nodes are discharged for a longer time before the latch turns on. The proposed approach is validated by applying it to an ULV comparator topology proposed in a previous work. Post-layout simulation results on a 130nm node demonstrate that input-referred noise and offset improve approximately 20% and 15%, respectively, while the energy-delay product of the comparator EDP remains essentially unchanged.