Low-Power Dual Dynamic Node Pulsed Hybrid Flip-Flop Featuring Efficient Embedded Logic

摘要

In this paper, we introduce a new dual dynamic node hybrid flip-flop (DDFF) and a novel embedded logic module (DDFF-ELM) based on DDFF. The proposed designs eliminate the large capacitance present in the precharge node of several state-of-the-art designs by following a split dynamic node structure to separately drive the output pull-up and pull-down transistors. The DDFF offers a power reduction of up to 37% and 30% compared to the conventional flip-flops at 25% and 50% data activities, respectively. The aim of the DDFF-ELM is to reduce pipeline overhead. It presents an area, power, and speed efficient method to incorporate complex logic functions into the flip-flop. The performance comparisons made in a 90 nm UMC process show a power reduction of 27% compared to the Semidynamic flip-flop, with no degradation in speed performance. The leakage power and process-voltage-temperature variations of various designs are studied in detail and are compared with the proposed designs. Also, DDFF and DDFF-ELM are compared with other state-of-the-art designs by implementing a 4-b synchronous counter and a 4-b Johnson up-down counter. The performance improvements indicate that the proposed designs are well suited for modern high-performance designs where power dissipation and latching overhead are of major concern.