In this tutorial, I will show you how to use Arduino to make a password access control circuit with LCD and keypad. You can check the code in the code section of the tinker cad. The circuit diagram is also shown here in the tinker cat. When we start the simulation we have to give it a default password which is 0000. Unlock it again press and hold a star button. If we give it the wrong password it will prompt us incorrect password message. To change the default password, first, you have to give it the correct password and then we have to press and hold the Hash button. Give it a new four-digit password, and it will ask for a new password again, Then the new password will be saved so now we can unlock the locker with the new password only.
Components Required:
| U1 | 1 | Arduino Uno R3 |
| KEYPAD2 | 1 | Keypad 4×4 |
| U2 | 1 | LCD 16 x 2 |
| K1 | 1 | Relay SPDT |
| T1 | 1 | NPN Transistor (BJT) |
| L1 | 1 | Light bulb |
| P1 | 1 | 12 , 5 Power Supply |
| D1 | 1 | Diode |
| R1 | 1 | 1 kΩ Resistor |
| R2 | 1 | 100 kΩ Resistor |
| R3 | 1 | 220 Ω Resistor |
Applications:
- Security Lockers
- Main Door Locks
- Office Acces Control
