Review of Full Adder Performance Analysis Using Kogge Stone Adder and Magnetic Tunnel Junction

Out of many adders like Ripple carry adder, carry look ahead adder, carry select adder and prefix adder, kogge stone adder is a high performance adder and also less affected by errors. Kogge stone adder is an advanced version of parallel prefix adders and also consists of less number of components thus delay is reduced. It consumes less power when compared with other adders, but it might consists of leakage current because of increase in stand-by power in the circuit. Leakage current is introduced in the circuit because of scaling of transistors. Thus VLSI designers found it difficult to reduce the parameters such as delay, power, area and leakage current simultaneously. To overcome this disadvantage, an MTJ(Magnetic Tunnel Juction) is introduced in the CMOS circuits. By the use of MTJs in the circuit the leakage current is reduced and zero standby power is obtained. A comparison analysis is done between a hybrid 4-bit MTJ/CMOS based full adder and 4-bit Kogge stone adder.