Skip to main content

7400 - Quad Two Input NAND Gate

7400 - Quad Two Input NAND Gate
7400 - Quad Two Input NAND Gate
74LS00 is part of the 74XXYY IC series. 74xxyy integrated circuits are logical gates of digital electronics. The 74LS00 IC has four NAND gates(NAND Gate is the combination of AND and NOT Gate). In addition, each door has two entrances. Hence the name QUAD TWO INPUT NAND GATE.
  
Pin Diagram of 7400 IC
7400 Pin DIagram
74LS00 is a 14-pin device. The chip is available in different packages and is chosen according to the needs. 

The description of each pin is given below.

Pin Number
Description
1
A1-INPUT1 of GATE 1
2
B1-INPUT2 of GATE 1
3
Y1-OUTPUT of GATE1
4
A2-INPUT1 of GATE 2
5
B2-INPUT2 of GATE 2
6
Y2-OUTPUT of GATE2
9
A3-INPUT1 of GATE 3
10
B3-INPUT2 of GATE 3
8
Y3-OUTPUT of GATE3
12
A4-INPUT1 of GATE 4
13
B4-INPUT2 of GATE 4
11
Y4-OUTPUT of GATE4
7
GND- Connected to ground
14
VCC-Connected to positive voltage to
provide smdksmkmpower to all four gates

 Internal Circuit Diagram of 7400 IC


7400 Internal Circuit Diagram
As you can see there are 4 NAND Gate inside 7400 IC and you can relate the Pin Description.

Below is the Truth Table of NAND Gate :

Input-1
Input-2
AND  O/P
NAND  O/P
1
1
1
0
0
1
0
1
1
0
0
1
0
0
0
1

NAND Gate using Transistors

7400 NAND Gate Equivalent Circuit Diagram

  • Both inputs A1 and B1 are LOW:
The two transistors Q1 and Q2 will be deactivated. Thus, the total supply voltage appears on the transistors Q1 and Q2. Since the output Y1 is only the voltage across the transistors Q1 and Q2, Y1 will be HIGH.
  • One of the Input is HIGH:
Only the relative transistor will be ON, leaving the other OFF. With this, the entire supply voltage appears on the transistor that is in the off state. As the output Y1 is the voltage across the two transistors Q1 and Q2, Y1 will be HIGH.
  • Both inputs are HIGH :
The two transistors will be ON and the voltage between them will be equal to zero. Because the output Y1 is the voltage at the two transistors Q1 and Q2, Y1 will be LOW.

After checking the cases, you can say that we have satisfied the truth table above. The output equation for the NAND gate can be given in the form, 7400 NAND Gate Equation

Applications


  • · General purpose logic
  • · Digital Electronics
  • · PCs and notebooks
  • · Servers
  • · ALUs
  • · Networking
  • · Digital systems

74LS00 Datasheet
Labels:
Location: India

Comments

Post a Comment

Popular posts from this blog

RGB Led Fading effect using Arduino

The RGB LED can emit different colors by mixing the 3 basic colors red, green and blue. So, it actually consists of 3 separate red, green and blue LEDs, packaged in one box. This is why it has 4 leads, one for each of the 3 colors and a common cathode or anode depending on the type of RGB LED. In this tutorial I will use a common cathode. Components required for this Project : RGB Led - Buy Arduino Uno - Buy Breadboard and Jumpers - Buy Circuit Diagram Above is the circuit diagram of the RGB Led and Arduino Uno , As you can see the ground pin  of the RGB LED is connected to the ground of the Arduino and other 3 pins of RGB Led are connected to the PWM Pins of Arduino Uno (9, 10, 11). Code int ledPin = 9;  int ledPin1 = 10; int ledPin2 = 11; void setup() {} void loop() {   for (int fadeValue = 0 ; fadeValue <= 255; fadeValue += 5)    {     analogWrite(ledPin, fadeValue);     delay(20);   }   for (int fadeValue = 255 ; fadeValue >= 0; fadeValue -
Post a Comment
Read more

Arduino Code Basics - C, Pins

Code Basics -Arduino C The Arduino uses a slightly reduced C/C++ programming language. In this recipe, we will remember a few basics of C/C++. Ensure that you have Arduino IDE Installed on your Laptop/PC. Here is a simple example of basic Arduino C/C++ manipulating two variables: // Global Variables  int var1 = 10;  int var2 = 20; void setup() {   // Only execute once when the Arduino boots   var2 = 5;   // var2 becomes 5 once the Arduino boots } void loop(){   // Code executes top-down and repeats continuously   if (var1 > var2) {  // If var1 is greater than var2 var2++; // Increment var2 by 1   } else {  // If var1 is NOT greater than var2     var2 = 0; // var2 becomes 0   }  } When we upload a sketch to the board, the Arduino software first compiles the code. If there is an error in the code, it will write it in the Status Display area and will stop the upload. If no errors are found, it will begin writing the compiled co
Post a Comment
Read more