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  • Sequential Logic Circuits: An Overview

    All of the circuits so far considered in this book have been combinational. This means that their outputs are dependent only upon the inputs at that time. We now turn our attention to sequential logic circuits whose outputs are also dependent upon past inputs, and hence outputs....

    2017/11/21 zhengxiaowei 104

  • What is Heuristic implementation

    Heuristic implementations can broadly be considered as those that are not produced by rigorous application of Boolean logic theory. (Remember that any truth table canĀ» in theory, be implemented in fundamental or minimised two-level form.)...

    2017/11/17 zhengxiaowei 140

  • Two-level Circuit Implementation

    Clearly the large number of gates required, the large number of inputs they must possess, and the fact that some signals must feed into many gates, means that this implementation is also impractical, although it is an improvement on the fundamental two-level form....

    2017/11/17 zhengxiaowei 99

  • Combinational Logic Design Example: A Four-Bit Adder

    In this section we consider the design of a four-bit adder; i,e. a circuit that adds together two four-bit binary numbers. This needs to be a combinational logic circuit and therefore serves as a useful exercise to apply what we have learnt....

    2017/11/17 zhengxiaowei 150

  • The Multiplexer as a Universal Logic Solution

    Because all 2m possible combinations of the m control lines of a multiplexer are fed to 2m AND gates then there is an AND gate for all of the fundamental product terms of the m variables....

    2017/11/16 zhengxiaowei 106

  • Common Combinational Logic Circuits

    There are a number of combinational logic circuits which are used so frequently that they are often considered to exist as circuit elements (like logic gates) in their own right. Note that the forms of these circuits given here are those that implement the basic functions....

    2017/11/16 zhengxiaowei 135

  • What is Boolean Algebra?

    Boolean algebra is the mathematical language of digital logic circuits, which are simply circuits built out of the three gates (operations) introduced above. It provides techniques for describing, ana...

    2017/11/15 zhengxiaowei 98

  • Basic Principles of Fundamentals and Introduction

    The algebra of a number system basically describes how to perform arithmetic using the operators of the system acting upon the system's variables which can take any of the allowed values within th...

    2017/11/15 zhengxiaowei 89