Design of In-Memory Parallel-Prefix Adders

Computational methods in memory array are being researched in many emerging memory technologies to conquer the ‘von Neumann bottleneck’. Resistive RAM (ReRAM) is a non-volatile memory, which supports Boolean logic operation, and adders can be implemented as a sequence of Boolean operations in the memory. While many in-memory adders have recently been proposed, their latency is exorbitant for increasing bit-width (O(n)). Decades of research in computer arithmetic have proven parallel-prefix technique to be the fastest addition technique in conventional CMOS-based binary adders. This work endeavors to move parallel-prefix addition to the memory array to significantly minimize the latency of in-memory addition. Majority logic was chosen as the fundamental logic primitive and parallel-prefix adders synthesized in majority logic were mapped to the memory array using the proposed algorithm. The proposed algorithm can be used to map any parallel-prefix adder to a memory array and mapping is performed in such a way that the latency of addition is minimized. The proposed algorithm enables addition in O(log(n)) latency in the memory array.

Fan-out enabled spin wave majority gate

By its very nature, Spin Wave (SW) interference provides intrinsic support for Majority logic function evaluation. Due to this and the fact that the 3-input Majority (MAJ3) gate and the Inverter constitute a universal Boolean logic gate set, different MAJ3 gate implementations have been proposed. However, they cannot be directly utilized for the construction of larger SW logic circuits as they lack a key cascading mechanism, i.e., fan-out capability. In this paper, we introduce a novel ladder-shaped SW MAJ3 gate design able to provide a maximum fan-out of 2 (FO2). The proper gate functionality is validated by means of micromagnetic simulations, which also demonstrate that the amplitude mismatch between the two outputs is negligible proving that an FO2 is properly achieved. Additionally, we evaluate the gate area and compare it with SW state-of-the-art and 15nm CMOS counterparts working under the same conditions. Our results indicate that the proposed structure requires 12x less area than the 15 nm CMOS MAJ3 gate and that at the gate level the fan-out capability results in 16% area savings, when compared with the state-of-the-art SW majority gate counterparts.

Fan-out enabled spin wave majority gate

By its very nature, Spin Wave (SW) interference provides intrinsic support for Majority logic function evaluation. Due to this and the fact that the 3-input Majority (MAJ3) gate and the Inverter constitute a universal Boolean logic gate set, different MAJ3 gate implementations have been proposed. However, they cannot be directly utilized for the construction of larger SW logic circuits as they lack a key cascading mechanism, i.e., fan-out capability. In this paper, we introduce a novel ladder-shaped SW MAJ3 gate design able to provide a maximum fan-out of 2 (FO2). The proper gate functionality is validated by means of micromagnetic simulations, which also demonstrate that the amplitude mismatch between the two outputs is negligible proving that an FO2 is properly achieved. Additionally, we evaluate the gate area and compare it with SW state-of-the-art and 15nm CMOS counterparts working under the same conditions. Our results indicate that the proposed structure requires 12x less area than the 15 nm CMOS MAJ3 gate and that at the gate level the fan-out capability results in 16% area savings, when compared with the state-of-the-art SW majority gate counterparts.

Design of ALU based on Majority Logic for Low Power Applications

Approximate calculations are a new nanotechnology paradigm for improving efficiency and reducing energy use. Most of the logic extends to many contemporary nanotechnological developments and is used for the design of digital circuits in its basic portion (3 input plurality, MV). This paper suggests implementations of additional compressors and ML multiplicators. An additional bit discovery circuit is used for the proposed compressors. The size of the multiplier is calculated by a control factor for the importance of different extra bits. The designs proposed are tested with hardware (for example, time frame and port complexity) as well as with error calculation. These designs have superior performance in terms of area and delay. The validity of the proposed designs is also shown by case tests of the error resistance implementation.

Application of fuzzy soft sets to analyze the statistical strength of S-boxes

For the evaluation of the substitution boxes, the majority logic criterion is used to analyze the statistical strength of the existing substitution boxes. The main objective of this paper is to make a decision on the analysis and selection of the most appropriate S-box based on a fuzzy soft-aggregation operator. Instead of the usual practice in which a single parameter is considered, we are considering several parameters that will definitely give us a comprehensive analysis of the S-boxes.