Optimized fault tolerant designs of the reversible barrel shifters using low power MOS transistors

Abstract

This paper demonstrates the reversible logic synthesis for the unidirectional, bidirectional and universal barrel shifters. The proposed shifters are constructed using only Fredkin and Feynman double gates. Initially, these two gates are designed and schematized using standard low power p-MOS 901 and n-MOS 902 models with average channel length 45 nm, delay 0.030 ns and density 1200 kgates/mm 2 . These schemas can detect faulty signal in its primary outputs. Thus, all the proposed shifters inherently tolerate single level fault. Moreover, the presented generalized algorithm for the proposed unidirectional barrel shifter has further been used to build base structures of the proposed bidirectional and universal shifters. In addition, lower bounds on the numbers of constant inputs and garbage outputs of the reversible barrel shifter have been proposed. It has been evidenced that the proposed circuits are constructed with these optimum constant inputs and garbage outputs. The simulation results prove the functional correctness of the proposed circuits. The comparative results show that the proposed designs perform much better and have significantly better scalability than the existing approaches. B Md. Shamsujjoha

Novel reversible CLA, optimized RCA and parallel adder/subtractor circuits

“…In the last decades, some of the arithmetic operations such as multiplication [10,11], counter [12,13], and division [14] are designed as reversible circuits that would be applied in some nanotechnology systems. The optimized and fault-tolerant design of reversible barrel shifters is presented by Shamsujjoha et al [40], which applies low power MOS transistors. Programmable Logic Array (PLA) is one of the main programmable circuits in the process of implementing combinational circuits.…”

Fault Detection Probability Evaluation Approach in Combinational Circuits Using Test Set Generation Method

“…With this application only two test vectors {001, 011} can give 100% fault tolerance. Design methodologies of reversible fault tolerant unidirectional, bidirectional and universal barrel shifters have been proposed having the capability of detecting errors at its primary outputs [28]. A fault model creation is important for fault diagnosis.…”