Comparison of noise tolerant precharge (NTP) to conventional feedback keepers for dynamic logic

Dynamic logic requires some sort of keeper to prevent the output node from floating and to provide acceptable noise immunity. A number of recent papers have advocated using a very weak complementary pMOS network in place of the conventional feedback keeper; such a technique is called Noise-Tolerant Precharge (NTP). This paper compares the delay and noise margin of NTP with conventional feedback keepers. Although NTP is more robust in that it can recover from a dynamic noise event, it is also 5-50 % slower than conventional feedback keepers with the same static noise margin