Implementation of Reversible Arithmetic and Logical Unit and Its BILBO Testing

Reversible logic is gaining more importance day by day, because of its feature of low power dissipation which is the basic need in designing nano electronic devices, bioinformatics, low power CMOS designs and quantum computing. Reversible logic is one which realizes n-input n-output functions that map each possible input vector to a unique output vector. It is a promising computer design paradigm for constructing arithmetic and logic units which are the basic building blocks of computer that do not dissipate heat. After designing a system, it is also equal important to test it. In this paper reversible ALU (Arithmetic and Logical Unit) performing four operations (Addition, Multiplication, Subtraction and Bit wise- AND) is implemented and the simulated results like power consumed, delay and area obtained are compared with that of conventional ALU. Testing is also done on proposed reversible ALU by using BILBO (Built—in Logic Block Observer) blocks, which was the first BIST (Built-in Self Test) architecture to be proposed and undergo wide spread use. The proposed reversible ALU is implemented and simulated using Verilog HDL in Xilinx 13.4 version.