This brief presents ultra low-voltage CML D-latch and D-Flip-Flop (DFF) topologies in deeply scaled CMOS technologies, able to operate at a supply voltage as low as 0.5 V (no other CML DFFs are able to operate at such a low supply voltage). The topology is based on a modified version of the Folded D-Latch, recently proposed by the authors. In this brief a detailed analysis on the minimum supply voltage allowed by the proposed topologies and a comparison with the one of the other low voltage topologies is also included. Post layout Simulations referring to a commercial 28 nm CMOS process and schematic level simulations adopting 14 nm predictive technology models are provided. They show the heavy advantages of the improved Folded DFF with respect to the state of the art.
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