Logic Gates Basic building blocks of any digital system It is an electronic

Logic gates basic building blocks of any digital

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Logic Gates Basic building blocks of any digital system. It is an electronic circuit having one or more than one input and only one output. The relationship between the input and the output is based on certain logic. AND gate, OR gate, NOT gate Comp Architecture - Digital Computer 28
AND Gate Comp Architecture - Digital Computer 29
OR Gate Comp Architecture - Digital Computer 30
NOT Gate NOT gate is also known as Inverter. It has one input A and one output Y. Comp Architecture - Digital Computer 31
NAND Gate A NOT-AND operation is known as NAND operation. It has n input (n >= 2) and one output. Comp Architecture - Digital Computer 32
NOR Gate A NOT-OR operation is known as NOR operation. It has n input (n >= 2) and one output Comp Architecture - Digital Computer 33
COMBINATIONAL CIRCUITS Comp Architecture - Digital Computer 34
Combinational circuit A connected arrangement of logic gates with a set of inputs and outputs Example : Adders, multiplexer, decoder… Comp Architecture - Digital Computer 35
Half Adder Comp Architecture - Digital Computer 36 A combinational logic circuit with two input and two output. Designed to add two single bit binary number A and B. This circuit has two outputs carry and sum.
Full Adder Comp Architecture - Digital Computer 37 Is developed to overcome the drawback of Half Adder circuit. It can add two one-bit numbers A and B, and carry c. The full adder is a three input and two output combinational circuit.
Circuit Diagram Comp Architecture - Digital Computer 38
Multiplexers A special type of combinational circuit. There are n-data inputs, one output and m select inputs with 2m = n. It is a digital circuit which selects one of the n data inputs and routes it to the output. Depending on the digital code applied at the selected inputs, one out of n data sources is selected and transmitted to the single output Y. E is called the strobe or enable input which is useful for the cascading Comp Architecture - Digital Computer 39
Block Diagram Comp Architecture - Digital Computer 40
Multiplexers come in multiple variations 2 : 1 multiplexer 4 : 1 multiplexer 16 : 1 multiplexer 32 : 1 multiplexer Comp Architecture - Digital Computer 41
Demultiplexers Performs the reverse operation of a multiplexer i.e. it receives one input and distributes it over several outputs. It has only one input, n outputs, m select input. A de-multiplexer is equivalent to a single pole multiple way switch Demultiplexers come in multiple variations 1 : 2 demultiplexer 1 : 4 demultiplexer 1 : 16 demultiplexer 1 : 32 demultiplexer Comp Architecture - Digital Computer 42
Demultiplexers Comp Architecture - Digital Computer 43
Decoder A decoder is a combinational circuit.

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• Fall '19
• Boolean Algebra, Logic gate, Combinational Circuits,  Examples of the digital systems