Parallel Prefix Ling Structures for Modulo 2^n-1 Addition

Parallel-prefix adders draw significant amounts of attention within general-purpose and application-specific architectures because of their logarithmic delay and efficient implementation in VLSI. This paper proposes a scheme to enhance parallel-prefix adders for modulo $2^n - 1$ addition by incorporating Ling equations into parallel-prefix structures. As opposed to previous research, this work clarifies the use of Ling equations for Modulo and provides enhancements to its implementation. Results are given in this work for a placed and routed design within a variation-aware 45nm technology. The implementation results show a significant improvement in delay and even a reduction in power dissipation.