International Journal of Research in Electronics and Computer Engineering (IJRECE)
There are two types of adders which are going to be explained in this paper viz. Ripple Carry Adder (RCA) and Look-ahead Carry Adder (LCA). These both kinds of adders are used for adding purpose. In this paper, both adders are designed for 4-bit addition operation. The difference between look ahead carry adder and ripple carry adder is proposed in this paper. Both these adders have been designed using a VHDL (Very high speed integrated circuit Hardware Description Language) tool named Xilinx ISE Design Suite 12.4-1. In VHDL tool, structural modeling is implemented on the above mentioned adders. This paper is focusing on difference between these adders based on their performance.