IC 9400 (7400) Overview
Type: Quad 2-input NAND gates
Series: 74xx TTL family (commonly called 7400)
Package: 14-pin DIP
Function: Contains four independent NAND gates
Pin Configuration
- Gate 1: Pins 1, 2 → Output 3
- Gate 2: Pins 4, 5 → Output 6
- Gate 3: Pins 9, 10 → Output 8
- Gate 4: Pins 12, 13 → Output 11
Pin 7 → GND
Pin 14 → Vcc (5V)
NAND Gate Truth Table
| A | B | Output (Y = NOT(A·B)) |
|---|---|---|
| 0 | 0 | 1 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
Key Idea
A NAND gate outputs LOW only when both inputs are HIGH.
Importance
- NAND is a universal gate
- Can be used to build NOT, AND, OR gates
- Foundation of digital circuit design
Applications
- Logic circuit design
- Digital electronics labs
- Flip-flops and counters