Electronics/Basic gates

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Basic Gates[edit]

There are 5 basic gates used in performing logic operations in Digital Electronic namely BUFFER gate, NOT gate, AND gate, OR gate, XOR gate . Each Logic Gate has A Symbol for easy to identify , a Mathematical Expression to identify mathmatic logic operation and a Truth Table to completely describe operation of the Logic Gate

Five Basic Logic Gates[edit]

Digital gates Symbol Logic Operation Mathematic Expression
BUFFER Cổng Tiếp (Buffer Gate) Y = BUFFER A Y = A
NOT NOT ANSI Labelled.svg Y = NOT A Y =
AND AND ANSI Labelled.svg Y = A AND B Y = A . B
OR Logic-gate-or-us.png Y = A OR B Y = A + B
XOR XOR ANSI Labelled.svg Y = A XOR B Y =

The Truth Table of the five basic logic gates above

A B Q = A Q = NOT A Q = A AND B Q = A OR B Q = A XOR B
0 0 0 1 0 0 0
0 1 0 1 0 1 1
1 0 1 0 0 1 1
1 1 1 0 1 1 0

Complement of Basic Logic gates[edit]

Basic Gates Combination Gates Symbol Mathematical Expression
BUFFER Logic-gate-inv-us.png Cổng NOT (NOT Gate) Buffer ANSI Labelled.svg Q = is NOT NOT A
Y = A
NOT Buffer ANSI Labelled.svg Cổng NOT (NOT Gate) Cổng NOT (NOT Gate) Y = is NOT A
NAND Logic-gate-and-us.png Cổng NOT (NOT Gate) NAND ANSI Labelled.svg Q = NOT A AND B
NOR Logic-gate-or-us.png Cổng NOT (NOT Gate) Logic-gate-nor-us.png Y = NOT A OR B
XNOR XOR ANSI Labelled.svg Logic-gate-inv-us.png XNOR ANSI Labelled.svg Q = NOT A XOR B

The Truth table of the combination gates above

A B Q = A Q = NOT A Q = A NAND B Q = A NOR B Q = A XNOR B
0 0 0 1 1 1 1
0 1 0 1 1 0 0
1 0 1 0 1 0 0
1 1 1 0 0 0 1

Summary[edit]

Gates Function Symbol
ANSI IEC
Buffer Buffer ANSI Labelled.svg Buffer IEC Labelled.svg
NOT gate (Inverter) NOT ANSI Labelled.svg NOT IEC Labelled.svg
AND gate AND ANSI Labelled.svg AND IEC Labelled.svg
NAND gate (NOT−AND) NAND ANSI Labelled.svg NAND IEC Labelled.svg
OR gate OR ANSI Labelled.svg OR IEC Labelled.svg
NOR gate (NOT−OR) NOR ANSI Labelled.svg NOR IEC Labelled.svg
XOR gate (Exclusive-OR) XOR ANSI Labelled.svg XOR IEC Labelled.svg
XNOR gate (NOT−exclusive−OR) XNOR ANSI Labelled.svg XNOR IEC Labelled.svg
A B Q = A Q = NOT A Q = A AND B Q = A OR B Q = A XOR B Q = A NAND B Q = A NOR B Q = A XNOR B
0 0 0 1 0 0 0 1 1 1
0 1 0 1 0 1 1 1 0 0
1 0 1 0 0 1 1 1 0 0
1 1 1 0 1 1 0 0 0 1