Logic Gates: Electronic Devices Semiconductors

If you are studying electronics, logic gates are a crucial concept to understand. These significant computer tools mostly rely on the Boolean function. To perform logical operations on one or more binary inputs and produce a single binary output, logic gates are used. The electronic circuits of a digital system are known as logic gates.

A logic gate’s primary requirements are that it accept a variety of inputs and, depending on the desired logic function, drive one or more outputs. Additionally, the output must be able to drive numerous inputs, necessitating the use of some sort of amplification. We refer to this as fan-out and state that an output can power, say, 50 inputs. The best amplifiers we have come up with so far use semiconductors. Amplification in electrical circuits entails some type of transistor operation. Continue reading to learn more about logic gates in electronic devices semiconductors.

Commonly Used Logic Gates

A truth table that lists all possible input-output combinations is present for each logic gate, which is represented by a symbol. In short, the truth tables make it easier to comprehend how logic gates behave. Semiconductor devices are used to create these gates. The top five logic gates in use are:

• NOT Gate: A NOT gate is a basic gate with a single input and output that simply inverts the input signal. As a result, when the input is “1,” the output is “0,” and vice versa. A NOT gate is also referred to as an inverter because of this characteristic. The truth table for a NOT gate is mentioned below:
  

• OR Gate: One output and two or more inputs make up an OR gate. When at least one of the inputs is 1, the logic of this gate predicts that the output will also be 1. In other words, when any of the input is high, the output is high. The truth table for an OR gate is given below:
  

• AND Gate: A single output and two or more inputs are also features of an AND gate. When all of the inputs are 1, this gate’s output is 1. In other words, when all of the inputs are high, the output is high. The truth table for AND gate is given below:
  

• NAND Gate: An AND gate and a NOT gate are the two gates that make up a NAND gate. Only when none of the inputs are 1, is the result 1. Alternatively, if all the inputs are low and at least one of them is high, the output will also be high. These gates are sometimes known as universal gates since the NAND gate can be used to realise the first three gates. The truth table for NAND gate is given below:
  

• NOR Gate: Simply put, a NOR gate consists of an OR gate and a NOT gate. Only when all inputs are zero is the output 1. Or perhaps all the inputs are low but the result is high. Since the NOR gate may be used to realise the first three gates, these are sometimes known as universal gates. The truth table for NOR gate is given below:
  

Why Are Electronic Semiconductor Devices Used in Logic Gates?

Devices that operate in accordance with temperature variation are known as semiconductors. Binary digits 1 and 0 are found in computational logic, respectively. Logic gate uses semiconductors because they are versatile switches that can quickly change between these states (0 for off and 1 for on). Complex computation-related logics are produced by the combinational or sequential logic of such devices. 

Talking about electronic semiconductor devices in logic gates, semiconductor devices like diodes are used to create logic gates. Diode combinations are created such that they provide the necessary logic. Reverse bias mode is used to prevent the current from passing whereas forward bias mode is used to pass the current. The desired logic is achieved by using a large number of diodes in forward and reverse bias mode. Students must understand the reason why electronic semiconductor devices are used in logic gates before moving ahead.

Composition of Logic Gates

Different voltage levels represent high or low binary situations. As the circuit analyses data, a terminal’s logic state can—and typically does—change frequently. The low state of the majority of logic gates is roughly zero volts (0 V), whereas the high state is roughly five volts (+5 V).

Transistors, diodes, and resistors can all be used to create logic gates. Commonly, resistors are used as pull-up or pull-down resistors. When there are any open logic gate inputs that need to be connected to a logic level 1 or 0, pull-up and pull-down resistors are used. This stops any incorrect gate switching. Pull-down resistors are wired to ground, and pull-up resistors are wired to Vcc (+5V) (0 V).

We hope this short article on Electronic Semiconductor Devices Used in Logic Gates has been helpful to you. Stay tuned to Embibe for such informative articles. Happy learning!