Design and Comparison of Optimized Low Power Reversible XS-3 Subtractor and Adder
Debashish Mahapatra, V. Shiva Prasad Nayak, B Nagavardban · 2018
Excess (XS)-3 code is a self-complementary binary code which is basically used for performing arithmetic operations in digital circuits. One very basic use of the XS-3 code is that, we can easily compute subtractions involving 9. This paper explains the design and implementation of 4-bit excess-3 subtractor and adder using reversible logic in a single circuit, which can perform both addition and subtraction operations on encoded XS-3 bits. The motivation behind using the reversible logic is to enhance the energy efficiency by reducing the power dissipation. The principle of reversible logic operations is that, they can dissipate arbitrarily less heat. According to Landauer's theory the energy dissipated per irreversible logic operation approaches the fundamental limit of kT*ln(2), where k is Boltzmann's constant and T is temperature. Hence, the use of reversible logic operation overcomes this issue. The simulation results of this project are obtained by using Xilinx ISE Design Suite 14.2 and for power analysis Cadence Virtuoso is used.