How to Use TM1638 8-Digit LED Display Module with 8 Buttons: Examples, Pinouts, and Specs

The TM1638 8-Digit LED Display Module with 8 Buttons is a versatile and compact component designed for both input and output in electronic projects. It features an 8-digit 7-segment LED display for visual output and 8 tactile buttons for user input. The module is powered by the TM1638 driver IC, which simplifies communication with microcontrollers by using a serial interface. This makes it an excellent choice for projects requiring numerical data display and user interaction.

• Digital clocks and timers
• Scoreboards and counters
• User interfaces for embedded systems
• Home automation control panels
• Educational and prototyping projects

• Driver IC: TM1638
• Operating Voltage: 5V DC
• Interface: Serial (3-wire: STB, CLK, DIO)
• LED Display: 8-digit 7-segment display
• Buttons: 8 tactile push buttons
• Current Consumption: ~80mA (varies with LED brightness)
• Dimensions: 75mm x 50mm x 15mm

The TM1638 module has a 5-pin header for interfacing with a microcontroller. Below is the pinout:

1. Power the Module: Connect the VCC pin to a 5V power source and the GND pin to ground.
2. Connect to Microcontroller: Use the DIO, CLK, and STB pins to interface with a microcontroller. These pins are used for serial communication.
3. Install Required Libraries: If using an Arduino, install the TM1638 or TM1638plus library for simplified control.
4. Write Code: Use the library functions to control the LED display and read button inputs.

• Power Supply: Ensure a stable 5V power supply to avoid flickering or erratic behavior.
• Pull-up Resistors: The module typically does not require external pull-up resistors as the TM1638 IC handles this internally.
• Avoid Overloading: Do not exceed the current rating of the module to prevent damage.
• Cable Length: Keep the connecting wires short to minimize signal degradation in serial communication.

Below is an example of how to use the TM1638 module with an Arduino UNO:

#include <TM1638.h> // Include the TM1638 library

// Define the pins connected to the TM1638 module
#define STB_PIN 10  // Strobe pin
#define CLK_PIN 11  // Clock pin
#define DIO_PIN 12  // Data input/output pin

// Create a TM1638 object
TM1638 module(STB_PIN, CLK_PIN, DIO_PIN);

void setup() {
  module.setupDisplay(true, 7); // Enable display with brightness level 7
  module.setDisplayToString("HELLO", 0); // Display "HELLO" on the module
}

void loop() {
  // Read button states
  byte buttons = module.getButtons();
  
  // If any button is pressed, display its number
  if (buttons > 0) {
    module.setDisplayToDecNumber(buttons, false, 0); 
    // Display the button number in decimal format
  }
}

• The TM1638 library simplifies communication with the module.
• The setupDisplay() function initializes the display with brightness control.
• The setDisplayToString() function displays a string on the 8-digit LED.
• The getButtons() function reads the state of the 8 buttons.

1. LED Display Not Working:

   • Ensure the VCC and GND connections are secure.
   • Verify that the STB, CLK, and DIO pins are correctly connected to the microcontroller.
   • Check the power supply voltage (should be 5V).

2. Buttons Not Responding:

   • Confirm that the DIO pin is properly connected.
   • Test the buttons for mechanical failure by pressing them directly.

3. Flickering Display:

   • Check for a stable power supply.
   • Reduce the brightness level using the setupDisplay() function.

4. No Communication with Microcontroller:

   • Ensure the correct pins are defined in the code.
   • Verify that the TM1638 library is installed and included in the sketch.

Q: Can I use the TM1638 module with a 3.3V microcontroller?
A: The module is designed for 5V operation. Use a level shifter to safely interface with 3.3V microcontrollers.

Q: How many TM1638 modules can I daisy-chain?
A: Multiple modules can be daisy-chained, but the exact number depends on the microcontroller's memory and processing capabilities.

Q: Can I control individual LEDs on the display?
A: Yes, the TM1638 library provides functions to control individual segments of the display.

Q: Is the module compatible with Raspberry Pi?
A: Yes, the module can be used with Raspberry Pi, but you will need to write or use a compatible library for SPI communication.

This documentation provides a comprehensive guide to using the TM1638 8-Digit LED Display Module with 8 Buttons in your projects. Happy tinkering!