How to Make 4-Digit Passcode Door Lock

Introduction

In today’s world, our security is of utmost importance. As the saying goes, “Prevention is better than cure,” it is always wise to secure our belongings before any unfortunate event happens. One of the most effective ways to keep unwanted intruders out of your home, office, or even your luggage is by locking them with a secure passcode door lock. Here we will learn how to make a 4-digit passcode door lock using a TM1637 module.

Explanation of 4-Digit Passcode Door Lock

Encoder:

An encoder is a device or software program that is used to convert data into a code to keep it secure and confidential. In the case of home security, the encoder takes the input that we provide from a numerical keypad and converts it into a unique code that operates a door lock. The encoder can be of various types depending on the type of input it can receive or the type of output it produces, such as rotary encoders, absolute encoders, incremental encoders, etc.

TM1637 Module:

TM1637 module is an electronic device used to interface a 7-segment display with any microcontroller. It works with any microcontroller that has a 2-wire I2C interface. The module is one of the most commonly used display drivers in the market. Its key features are 4 digit LED display, easy wiring, low power consumption, and compatibility with most Arduino and Raspberry Pi boards.

**How to Make 4-Digit Passcode Door Lock**

Circuit Diagram of 4-Digit Passcode Door Lock

This project can be designed using a few basic components. The circuit diagram of this project is shown below.

How to Make 4-Digit Passcode Door Lock Circuit Diagram — **4-Digit Passcode Door Lock Circuit Diagram**

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Components List of 4-Digit Passcode Door Lock

Following is the list of all components used in this project:

1x Arduino Nano
1x Encoder
1xTM1637 module
1X BC547 Transistor
1X 1N4148 Diode
1x Solenoid lock
1x 1K Resistor
1x 5V Relay
2x 2 Pin Terminal Blocks
JUMPER WIRES

Project Zip File:

Gerber File:

Now that we know what an encoder and a TM1637 module are, let’s dive into how to make a 4-digit passcode door lock using these two components.

Materials Required:

A complete list of material required is already provided above in Components List section. Gather them all to continue building the project.

Steps Building Project:

Connect the Arduino Nano and TM1637 module to the board. Connect GND and VCC of the TM1637 module to GND and +5V of the Arduino.

Connect the encoder to the Arduino. Make all connections according to the circuit diagram which is already provided above.

Download the code from the above link provided and upload the it to the Arduino. The code will be responsible for taking the input and displaying it on the 7-segment display. The encoder will be used to check if the entered code matches the pre-set 4-digit passcode.

Once the code is uploaded, a 4-digit passcode can be set. The passcode can be stored in the Arduino code by replacing the variable ‘password’ with the 4-digit code.

Congratulations! With the 4-digit passcode door lock, you can be sure that your belongings are secure from intruders.

Conclusion of 4-Digit Passcode Door Lock

In conclusion, making a 4-digit passcode door lock using an encoder and a TM1637 module is straightforward with the right components and a little bit of programming knowledge. The encoder converts the input from a numerical keypad into a unique code that operates the door lock, while the TM1637 module displays the entered code on a 4-digit 7-segment display. By following the above steps, you can secure your home, office, or luggage with a customized passcode door lock system.