I. INTRODUCTION
A processor is a main part of any digital system. And an ALU is one of the main components of a micro-processor. To give a simple analogy, CPU works as a brain to any system & and ALU works as a brain to CPU. So it’s a brain of computer’s brain. They are consists of fast dynamic logic circuits and have carefully optimized structures. Of total power consumption in any processor, CPU accounts a significant portion of it. ALU also contribute to one of the highest power-density locations on the processor, as it is clocked at the highest speed and is busy mostly all the time which results in thermal hotspots and sharp temperature gradients within the execution core. Therefore , this motivate us strongly for a energy-efficient ALU designs that satisfy the high-performance requirements, while reducing peak and average power dissipation.[1,2] Basically ALU is a combinational circuit that performs arithmetic and logical operations on a pair of n bit operands e.g. A [0:7] & B [0:7] for 8 bits. The typical internal structure of a 8 bit ALU is shown in Fig.1. The architecture can be modified similarly for lower bits. Our work is divided into following sections: Section (II) give description of various units and operations of ALU, Section (III) briefly presents the designing of various ALU components such as Shifter, adder, subtractor etc. using conventional complementary design. Section (IV) present the GDI technique. Section (V) present the simulation results and performance analysis of various ALU blocks with complementary and GDI technique and comparison of their performance & optimized area. Finally the work is concluded in Section (VI)
II. ARITHMETIC LOGIC UNIT
2.1 Arithmetic Unit
Employing fast and efficient ad...
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...egy for Barrel Shifter Using Mux at 180nm Technology Node ”, International Journal of Science and Modern Engineering (IJISME), ISSN: 2319-6386, Volume-1, Issue-8, July 2013
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[9] Arkadiy Morgenshtein, Alexander Fish, and Israel A. Wagner, “Gate-Diffusion Input (GDI): A Power-Efficient Method for Digital Combinatorial Circuits”, IEEE Transactions On Very Large Scale Integration (VLSI) Systems, Vol. 10, No. 5, October 2002
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...hborhood, additive CA are ideally suited for V LSI implementation. Different applications ranging from V LSI test domains to the design of a hardwired version of different CA based schemes have been proposed.
...y the dependence of critical charge variation on gate length variation, threshold variation, and correlation between gate lengths. Also a simple model is presented to estimate critical charge variation without Monte Carlo simulation cite{4063059}.
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In today’s world most of the applications uses FPGA to process the data in the real time and prototyping. The demand for FPGA is increasing because of its performance and reprogramability. The basic building block of FPGA is Logic Block(Configuration Logic Block or Versatile). Many applications, vendors claims the utilization of FPGA or FPGA density in terms of gate counts.
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The current conveyor is a basic building block that can be implemented in analog circuit design. This was introduced by Sedra and Smith in 1968 but its real advantages and innovative impact was not clear at that time. In recent years, current-mode circuits have emerged as an important class of circuits with properties of accuracy, high frequency range and versatility in a wide range of applications. Current conveyor represents the emerging class of high performance analog circuit design based on current mode approach. It has simple architecture, wider bandwidth and capability to operate at low voltage. The c...
It is a semiconductor device consisting of` electronic logic circuits`. A microprocessor accomplishes the tasks of a computer’s CPU on a single IC (integrated circuits) or multiples ICs. These IC individually are made of many small electrical components like transistors, resistors etc. It` is the brain of the computer and is also `referred to as a logic chip.
In the past few decades, one field of engineering in particular has stood out in terms of development and commercialisation; and that is electronics and computation. In 1965, when Moore’s Law was first established (Gordon E. Moore, 1965: "Cramming more components onto integrated circuits"), it was stated that the number of transistors (an electronic component according to which the processing and memory capabilities of a microchip is measured) would double every 2 years. This prediction held true even when man ushered in the new millennium. We have gone from computers that could perform one calculation in one second to a super-computer (the one at Oak Ridge National Lab) that can perform 1 quadrillion (1015) mathematical calculations per second. Thus, it is only obvious that this field would also have s...
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George Stibitz constructed a 1-bit binary adder suing relays in 1937. This was one of the first binary computers. In the summer of 1941 Atanasoff and Berry completed a special purpose calculator for solving systems of simultaneous linear equations, later called "ABC" ( Atanasoff Berry Computer). In 1948 Mark I was completed at Manchester University. It was the first to use stored programs. In 1951 whirlwind was the first real-time computer was built for the US Air Defense System.
Moor’s Law: The number of transistors incorporated in a chip will approximately double every 24 months. (Moore, 1965)
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Computers are very complex and have many different uses. This makes for a very complex system of parts that work together to do what the user wants from the computer. The purpose of this paper is to explain a few main components of the computer. The components covered are going to be system units, Motherboards, Central Processing Units, and Memory. Many people are not familiar with these terms and their meaning. These components are commonly mistaken for one and other.
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