Basic Gates and Functions

Basic Gates and Functions

Digital circuits contain 'logic gates' that perform logic operation on binary numbers. 

AND Logic Gate 

The AND gate is an electronic circuit that gives a high output (1) only all inputs give are high.

AND Logic Gate and Truth Table

Application of AND Gate

1. AND gate used in the automatic fan control system. 

2. 'Fan On' only the daytime and hot condition.

Automatic Fan Control System

OR Logic Gate
The OR gate is an electronic circuit that gives a high output (1) if one or more of its inputs are high.

OR Logic Gate and Truth Table

Application of OR Gate

1. Shutdown command operates only the temperate or pressure or both higher than normal condition. 

2. Shutdown command does not operates, when temperature and pressure normal condition. 

Automatic Plant Shutdown System

NAND Logic Gate
1. NAND gate is a electronic circuit that gives a low output (0), if two inputs are high.

NAND  Logic Gate and Truth Table

Application of NAND Gate

1. When all the fans are working, the input to the NAND gate is 11 and the output is zero.

1. If any one of the fan stops working, the output of the NAND gate becomes 1, which activates the alarm.

NOR Logic Gate
NOR gate is a electronic circuit that gives a high output (1), if two inputs are low.

NOR  Logic Gate and Truth Table

Application of NOR Gate

1. If the machine lid is open or machine is overloaded, the output of the sensor is set to 1, Producing output of the NAND gate '0'.

2. Hence switch off the circuit.