Reversible Logic Synthesis of Fault Tolerant Carry Skip BCD Adder

Reversible logic is emerging as an important research area having its application in diverse fields such as low power CMOS design, digital signal processing, cryptography, quantum computing and optical information processing. This paper presents a new 4*4 parity preserving reversible logic gate, IG. The proposed parity preserving reversible gate can be used to synthesize any arbitrary Boolean function. It allows any fault that affects no more than a single signal readily detectable at the circuit's primary outputs. It is shown that a fault tolerant reversible full adder circuit can be realized using only two IGs. The proposed fault tolerant full adder (FTFA) is used to design other arithmetic logic circuits for which it is used as the fundamental building block. It has also been demonstrated that the proposed design offers less hardware complexity and is efficient in terms of gate count, garbage outputs and constant inputs than the existing counterparts.Comment: 9 pages, 7 figures, 5 table

MF-RALU: design of an efficient multi-functional reversible arithmetic and logic unit for processor design on field programmable gate array platform

Most modern computer applications use reversible logic gates to solve power dissipation issues. This manuscript uses an efficient multi-functional reversible arithmetic and logical unit (MF-RALU) to perform 30 operations. The 32-bit MF-RALU includes arithmetic, logical, complement, shifters, multiplexers, different adders, and multipliers. The multi-bit reversible multiplexers are used to construct the MF-RALU structure. The Reduced instruction set computer (RISC) processor is designed to realize the functionality of the MF-RALU. The MF-RALU can perform its operation in a single clock cycle. The 1-bit RALU is developed and compared with existing approaches with improvements in performance metrics. The 32-bit reversible arithmetic units (RAUs) and reversible logical units (RLUs) are constructed using 1-bit RALU. The MF-RALU and RISC processor are synthesized individually in the Vivado environment using Verilog-HDL and implemented on Artix-7 field programmable gate array (FPGA). The MF-RALU utilizes a <11% chip area and consumes 332 mW total power. The RISC processor utilizes a <3% chip area and works at 483 MHZ frequency by consuming 159 mW of total power on Artix-7 FPGA

Design and analysis of efficient QCA reversible adders

Quantum-dot cellular automata (QCA) as an emerging nanotechnology are envisioned to overcome the scaling and the heat dissipation issues of the current CMOS technology. In a QCA structure, information destruction plays an essential role in the overall heat dissipation, and in turn in the power consumption of the system. Therefore, reversible logic, which significantly controls the information flow of the system, is deemed suitable to achieve ultra-low-power structures. In order to benefit from the opportunities QCA and reversible logic provide, in this paper, we first review and implement prior reversible full-adder art in QCA. We then propose a novel reversible design based on three- and five-input majority gates, and a robust one-layer crossover scheme. The new full-adder significantly advances previous designs in terms of the optimization metrics, namely cell count, area, and delay. The proposed efficient full-adder is then used to design reversible ripple-carry adders (RCAs) with different sizes (i.e., 4, 8, and 16 bits). It is demonstrated that the new RCAs lead to 33% less garbage outputs, which can be essential in terms of lowering power consumption. This along with the achieved improvements in area, complexity, and delay introduces an ultra-efficient reversible QCA adder that can be beneficial in developing future computer arithmetic circuits and architecture

QUANTUM COMPUTING AND HPC TECHNIQUES FOR SOLVING MICRORHEOLOGY AND DIMENSIONALITY REDUCTION PROBLEMS

Tesis doctoral en período de exposición públicaDoctorado en Informática (RD99/11)(8908

Fault tolerance in reversible logic

In recent years reversible logic has offered a promising alternative to traditional logic circuits. Reversible logic introduces a mechanism which allows theoretically zero energy dissipation by eliminating the possibility of information loss. However, it is also desirable that all computation should ideally be done in a fault tolerant manner. To address this we propose techniques to achieve fault tolerance in reversible logic based on a passive hardware redundancy technique. We propose two new designs for a reversible majority voter circuit that can be used to implement fault masking. Comparisons to existing designs are presented in terms of cost metrics such as gate count, garbage outputs, constant inputs, and quantum cost. Comparative failure probability analysis of the proposed voter circuits is also provided. Simulation results of the voter circuit failure probabilities over different numbers of trials are also presented. Our approach can be used to determine the circuit failure probability by using the gate failure probabilities. The proposed methodology can provide useful information for future reversible gate fabrication and designing future fault tolerant reversible circuits

Synthesis, testing and tolerance in reversible logic

In recent years, reversible computing has established itself as a promising research area and emerging technology. This thesis focuses on three important areas of reversible logic, which is an area of reversible computing. Firstly, this thesis proposes a transformation based synthesis approach for realizing conservative reversible functions using SWAP and Fredkin gates. This thesis also proposes ten templates for optimizing SWAP and Fredkin gates-based reversible circuits. Secondly, this thesis proposes an approach for the design of online testable reversible circuits. A reversible circuit composed of NOT, CNOT and Toffoli gates can be made online testable by adding two sets of CNOT gates and a single parity line. Finally, we have proposed an approach to achieve fault tolerance in reversible circuits. A design of a 3-bit reversible majority voter circuit is presented. This voter circuit can be used to design fault tolerant reversible circuits

The 1991 3rd NASA Symposium on VLSI Design

Papers from the symposium are presented from the following sessions: (1) featured presentations 1; (2) very large scale integration (VLSI) circuit design; (3) VLSI architecture 1; (4) featured presentations 2; (5) neural networks; (6) VLSI architectures 2; (7) featured presentations 3; (8) verification 1; (9) analog design; (10) verification 2; (11) design innovations 1; (12) asynchronous design; and (13) design innovations 2