# Category Archives: Digital Electronics

## Basic logic gates

In any digital electronics textbook you will find description on various logic operations and different logic gates; e.g. AND, OR, NOT, NAND, NOR, XOR and XNOR. But AND, OR and NOT these three gates are known as basic gates. Because you can design any other logic gates or digital electronics circuits using only these three… Read the rest

## Exclusive NOR or XNOR gate

In the exclusive OR or XOR gate section we have seen how XOR gate works and how simple it is. Exclusive NOR or XNOR gate is also like a XOR gate, the only difference is we put a NOT logic in the output of a XOR gate and XOR gate becomes a XNOR gate. That… Read the rest

## Exclusive OR gate (XOR gate)

Exclusive OR gate is also known as EOR gate or EXOR gate. This logic gate may have two or more inputs and XOR gates always have one output. Its logic is as simple as previously discussed logic gates. Just think the meaning of the word ‘exclusive’; XOR gate output logic is true (high) when only… Read the rest

## NOR gate

In this series of ‘digital electronics’ I have already discussed about three basic gates and NAND gate, which is a widely used gate in digital electronics. Now my topic is NOR gate. Definition of NOR operation NOR operation is a Boolean operation where output is true if all operands are false. In terms of NOR… Read the rest

## NAND gate

AND, OR and NOT are three basic operations in Boolean algebra; and AND, OR and NOT gates are three basic gates in digital electronics. Actually all logic gates are made of these three gates. Definition of NAND operation NAND operation is a Boolean operation where output is false only if all operands are true. In… Read the rest

## NOT gate or inverter

NOT gate is a logic gate circuit which performs NOT operation on input. Its output logic level is always opposite to input. In other words NOT gate inverts its input. Unlike AND and OR gates NOT gate always has single input. NOT gate symbol Truth table for NOT operation Figure below shows a NOT gate… Read the rest

## NOT operation

NOT operation is the last basic Boolean operation. We have seen in OR and AND operation that these are performed on two or more inputs. But NOT operation is performed on single input. NOT operation simply gives opposite logic state of its input logic state. i.e. if input logic is 1 output will be 0… Read the rest

## OR gate

OR gate is a digital circuit which performs OR operation on inputs. In OR operation section I discussed about the Boolean logic, OR operation. If any input is true the output is true. So OR gate is a digital circuit where output goes to high state (1) if any of the inputs are high. The… Read the rest

## OR operation

In AND operation section I have mentioned that there are three basic Boolean operations in digital electronics and OR operation is one of them. In OR operation, if only one input is true then the output will be true. In other words with OR operation we check whether any of the inputs are true (in… Read the rest

## AND gate

AND gate is a digital circuit which performs AND operation on inputs. As I discussed in previous section that AND gate gives high output when all inputs are high. In other cases its output must be low (i.e. 0). So we need to design a circuit in that way. Truth table for AND gate Figure… Read the rest