7404 is a NOT gate IC. It consists of six inverters which perform logical invert action. The output of an inverter is the complement of its input logic state, i.e., when input is high its output is low and vice versa.
Pin Description:
| Pin No | Function | Name |
| 1 | Input/output of 1st inverter | Input1 |
| 2 | Output1 | |
| 3 | Input/output of 2nd inverter | Input2 |
| 4 | Output2 | |
| 5 | Input/output of 3rd inverter | Input3 |
| 6 | Output3 | |
| 7 | Ground (0V) | Ground |
| 8 | Output/input of 4th inverter | Output4 |
| 9 | Input4 | |
| 10 | Output/input of 5th inverter | Output5 |
| 11 | Input5 | |
| 12 | Output/input of 6th inverter | Output6 |
| 13 | Input6 | |
| 14 | Supply voltage; 5V (4.75 – 5.25 V) | Vcc |