Easy-Peasy Logic GatesA guide to understanding basic logic gatesImeshaBlockedUnblockFollowFollowingMay 12Photo by Bartosz Kwitkowski on UnsplashWe all know that letters are the foundation of a language in order to create the words.
Similarly, logic gates act as basic components when creating digital circuits in the electronic world.
Just like vowels in an alphabet, there are few important types of logic gates.
In this article, we will learn about the basic logic gates and their functionality.
The BasicsThe three basic types of logic gates are:NOTORAND.
Based upon the aforementioned gates, the following logic gates are created:NANDNORXORXNOR.
Usually, a logic gate symbol has input on the left and output on the right as shown in the diagrams below.
Standard Logic Gate Symbol of a Single Input / Single Output unit (Buffer)Standard Logic Gate Symbol of a Double Input / Single Output unit (AND ate)Binary and DecimalBefore discussing truth tables, it is necessary to know the background of binary and decimal.
We all are familiar with decimal numbers (0, 1, 2, 3, 4, 5, 6, 7, 8, 9), which we use in daily calculations.
This number system has the base of 10.
In a similar manner, the binary numbers (0, 1) can be used to represent decimal values where the binary numbers have the base of 2.
The importance of using binary here is to represent the switching status or voltage status of a digital component: 0 to indicate Low Voltage/Low Signal and 1 to indicate High Voltage/High Signal.
Thus, the Boolean algebra was initiated.
Next, we will discuss each gate separately.
This includes the logic behind the gate, its standard symbol, and the truth table of the gate.
NOT GateThe NOT gate is also identified as the Inverter.
This is because the output of NOT gate is always the complete opposite of the input.
If the input is high, the output will be low and vice versa.
The standard symbol of the NOT gate can be expressed as below.
Standard NOT Gate SymbolAccording to the diagram, the X denotes the input signal where Z is the output signal.
Therefore, the truth table can be written as follows:The truth table for the NOT gateOR GateOR gate has two inputs and one output.
If either input signal is high, the output will be high.
In other words, the operation of the OR gate is similar to the Addition (+) of each input.
The standard symbol of the OR gate can be expressed as below.
Standard OR Gate SymbolAccording to the diagram, the X and Y denote the input signals where Z is the output signal.
Therefore, the truth table can be written as follows:The truth table for the OR gateAND GateAND gate also has two inputs and one output, like the OR gate.
In this logic gate, the output signal is high only if the two gate input signals are high.
Otherwise, the output will be zero.
The logic operation of the gate is similar to the multiplication (×) operation.
The standard symbol of the AND gate can be expressed as below.
Standard AND Gate SymbolAccording to the diagram, the X and Y denote the input signals where Z is the output signal.
Therefore, the truth table can be written as follows:The truth table for the AND gateHope you enjoyed and learned about basic logic gates by reading this small piece.