AND Gates

Welcome to AND gates. In this video, you’ll learn how to determine AND gate operations. to show the AND gates operations you’ll see a truth table, switch illustration, Boolean algebra equation, and an application. The AND gate is a logic device that has two or more inputs and one output. The schematic symbol for a three input AND gate is shown above. The AND gate produces a logic one at its output only when all inputs are high.

A logic low state is produced when one or more of the 00:48 - inputs are low. As each row is highlighted the truth table shows the changes in the input and output states of the and gate. Notice that the output X is only 1 when all of the inputs are 1. The series circuit can be used to illustrate the operation of the AND gate. 3 switches labeled A, B, and C are used to represent the inputs and a light bulb, labeled X, is used to represent the output. An open switch represents a logic 0 and a closed switch represents a logic 1. When the light bulb is on it represents a logic 1 and when it is off it represents a logic 0. The only time the light bulb is on is when switch A is closed and switch B is closed and switch C is closed. The AND gate operation can also be expressed by a Boolean algebra equation. The symbol for an AND operation is a center dot that is read and it does not mean multiplication.

For the three input AND gate described previously, the equation is: 01:58 - X = A and B and C which simply means that the output of the gate is a logic 1 when A and B and C inputs are all in their 1 states. Finally, an AND gate operation is used to drill a machine part. Notice that the AND gate circuit on this drill press provides a safety feature which prevents the operator from placing a hand between the drill bit and stock. To operate, the stock is detected by a sensor and both buttons must be pushed simultaneously to activate the drill. Thank you for watching AND gates. If this was helpful, why not subscribe and give us a like! .