# Logical OR (OR) Gate / Logic OR Gate

In this beautiful series where we examine logic doors, today we will examine the logical "OR" door. The exit status of the "OR" logic door will be any kind of "1" (High), regardless of what the other is, when any of its entrances are at the logic level "1". In other words, as long as one of the entries is "1", the output will always be "1". As we learned in our previous logistics doors article, there is a mathematical formula in this logistics door. In fact, these mathematical expressions make our job very easy when installing and analyzing these circuits. For this reason, the mathematical expression of our OR logical door is as follows. ## Simple OR Log Door Circuit

At this point, let's first set up our "OR" circuit with the transistor. At this point, we are establishing our circuit, which appears just below, with transistor and resistance. Actually, it's as simple as it looks. We control our output through the A and B inputs located on the left side of the image. As with every article, we do not forget to mention the purpose of use of our logistics doors in this article. Logic Doors are circuits that are used to produce the desired logical function, and the logical gate "OR" that we are learning today is one of them. Today, the symbol of the "OR" logic door is as follows. Another important issue that comes up after learning the mathematical expression and symbol of our logical "OR" door will be the table of accuracy. At this point, we're going to pull out two different fact sheets. The first one will be the "OR" gate with 2 inputs and the second will be the logic with 3 entries. So how do we get these paintings out based on what we've learned so far? That's why we need to examine the mathematical expression we learned above a little more. At this point, the accuracy table of our logical "OR" circuits with inputs 2 and 3 will be as follows.

## Table of Logical "OR" Gate with 2 Inputs ## Table of Logical "OR" AND Gate with 3 Inputs So what will our mathematical expression look like if we put together multiple logical "OR" doors. Let's see it together: As you can see in this circuit, multiple "OR" logistics doors stand together. As we all know, we're going to face more and more complex problems. At this point, the main thing is to solve them with the experiences we have gained up to that point. As you can see here, when you follow the A, B, C, D entries as we learned above, everything is actually very easily understood. Finally, let's learn about the logistics door integrations of TTL and CMOS families.