of Pharmaceutical , Biological and Chemical Sciences Review on Performance of Adders for VLSI Applications

In this paper an extensive study on several adders has been manifested to design VLSI applications. Adder circuits plays a major role to modify or design a multiplier. Imprecise adder is one of the design where used in increasing the performance and power efficiency and approximate adders are for error detection and correction.16T full adders is also used to fast and energy efficient adder. An adder is digital circuit that performs addition of numbers. Approximate adders are widely being used in order to improve performance in error resilient applications. Error detection is done by using probability method. Ripple carry adder are shown which it has better power efficiency, performance speed. Adders are being optimized by using transistor sizing technique in order improve consumption and transistor count. In order to improve the energy efficiency and speed we use a technique i.e. pipelined or parallel structure. Variable latency adders are embedded in order to reduce the average addition time by the help of speculation. Xor-Xnor 1-bit full adder which gives best performance than others circuits. As we take one of the adder to design a multiplier.