QCA based approximate multipliers and adders method

Abstract Integrated circuits have become much smaller, robust and less expensive revolutionizing the electronics world. Over the decades, CMOS have played a crucial role in the integrated circuits. The exponential scaling and increase in processing speed have been provided by CMOS technology for implementing VLSI systems. The present CMOS technology does not sustain the growth levels expected by the semiconductor industry. One of the most important problems with CMOS is quantum tunneling through the insulators. Although the current generation of CMOS technology is 22 nm, several consequences in terms of oxide thickness, power dissipation, leakage currents and electron migration may arise in the future. Nanotechnology is proposed as a solution to the problem because it overcomes the existing power dissipation and also because of the growing demand for denser and faster integrated circuits. Quantum dot-Cellular Automata technology (QCA) emerges as an effective alternative of CMOS-VLSI. Any digital circuit can be implemented by utilizing the QCA-based majority gates. In this research, fast adder such as parallel prefix adder with compressor technique and multiplication operations are carried out by using the majority logic. In order to obtain results, Xilinx ISE simulation tool is utilized. The simulation is executed by majority gates using parallel prefix adder like Brent Kung adders to perform the accurate and approximate multiplication operations. Simulation results are obtained with reduced cell count, latency and power consumption when compared with the existing systems. Additionally, a proficient adder is integrated to reduce the complexity of addition related operations.