# Implementation of Decoder using Logic Gates.docx -...

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Implementation of Decoder usingLogic GatesObjectives:To implement 2 X 4 Decoder.To implement 3 X 8 Decoder.Circuit equipments:IC 74LS139 IC 74LS138Back ground theory:Decoder:The name “Decoder” means to translate or decode coded information from one format into another, so a binary decoder transforms “n” binary input signals into an equivalent code using 2noutputs.Binary Decodersare another type of digital logic device that has inputs of 2-bit, 3-bit or 4-bit codes depending upon the number of data input lines, so a decoder that has a set of two or more bits will be defined as having an n-bit code, and therefore it will be possible to represent 2npossible values. Thus, a decoder generally decodes a binary value into a non-binary one by setting exactly one of its noutputs to logic “1”.If a binary decoder receives n inputs (usually grouped as a single Binary or Boolean number) it activates one and only one of its 2noutputs based on that input with all other outputs deactivated.
So for example, an inverter ( NOT-gate) can be classed as a 1-to-2 binary decoder as 1-input and 2-outputs (21) is possible because with an input A it can produce two outputs A and A (not-A) as shown.Then we can say that a standard combinational logic decoder is an n-to-mdecoder, where m ≤ 2n, and whose output, Q is dependent only on its present input states. In other words, a binary decoder looks at its current inputs, determines which binary code or binary number is present at its inputs and selects the appropriate output that corresponds to that binary input.

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Term
Summer
Professor
N/A
Tags
Binary numeral system, Input output, binary input signals
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