A Simple Keeper Topology to Reduce Delay Variations in Nanometer Domino Logic

In this paper, a simple topology to reduce delay variations in domino logic gates is discussed. According to a previous analysis by the same authors, the feedback loop implemented by the keeper transistor and the output inverter gate is responsible for a delay variability increase, compared to static CMOS logic. The proposed strategy reduces the loop gain associated with this feedback loop, and hence its impact on delay variations. As a result, delay variations associated with the keeper insertion are lowered by approximately 50%, with no penalty in area, noise margin and nominal performance.