TM1637 4-Digit 7-Segment Red Display Module

Four 0.36″ red 7-segment displays with center colon and TM1637 serial LED driver.

DESCRIPTION

The TM1637 4-Digit 7-Segment Red Display Module incorporates four 0.36″ red 7-segment displays along with the TM1637 serial LED driver.

PACKAGE INCLUDES:

• TM1637 4-Digit 7-Segment Red Display Module

KEY FEATURES OF TM1637 4-DIGIT 7-SEGMENT RED DISPLAY MODULE:

• Four 7-Segment LED Displays with 0.36″ high red digits
• Center colon display
• Built-in TM1637 LED Driver
• 2-wire serial interface for easy hookup to uC
• 3.3 and 5V compatible

The display has a center colon commonly used for clock applications, but the display also works fine for some other numeric or hex display purposes.

The TM1637 is a driver that supports many functions including on/off and brightness control of the LEDs as well as accessing each of the digits.  Once the display is updated by the MCU, the TM1637 takes care of all the work of keeping the display refreshed, so it removes that overhead from the MCU so it can be off doing other things.

These modules communicate via a 2-wire bus, so they only require 2 data pins plus power and ground.  The bus is specific to this device but there are libraries available such as the “TM1637.h” library for Arduino that hides all the dirty details and makes communicating with the display straightforward.

Module Connections

There is a 4-pin right angle male header on the module for making connections.

1 x 4 Header

• CLK =   Clock Input.  Connect to any digital pin on MCU.
• DIO =   Data I/O.  Connect to any digital pin on MCU.
• VCC =   3,3 or 5V to match MCU power.
• GND =  Ground.  Must be common with MCU ground.

OUR EVALUATION RESULTS:

These are useful modules and an easy way to get a number display up and running on a project.  The center colon works well for displaying a clock or stop watch, but does not need to be used if displaying other data.

The program below implements a simple humidity/temperature measurement device using either the DHT11 or DHT22 humidity/temperature sensors and displays both the humidity and temperature on the TM1637 display.

The program uses the “TM1637.h” library to implement  basic functionality of the display module and the ‘DHT.h’ library for the humidity sensor.  The DHT.h library also requires that the Adafruit_Sensor library be installed.

The example uses pins 2, 3 and 4 for making connections to the humidity sensor and the TM1637, but these can be any 3 digital pins.

TM1637 4-Digit 7-Segment Display Module Example Program

/* TM1637 4-digit Example
Uses a humidity sensor DH11 or DH22 type and reports the 
temperature and humidity on the TM1637 4-digit display.

Program assumes temperature and humidity reading will always be 2 digits.

Can use any 3 digital pins for connections.  Example uses pins 2-4.

Uses Adafuit dht.h library for humidity.  This also requires Adafruit_Sensor library
Uses TM1637.h library for display
Written by Ken Hahn
Released to public domain
*/
#include "DHT.h"
#include "TM1637.h"
 
int const DHT_PIN = 2; // Humidity sensor output pin
int const CLK = 3;     // TM1637 Clock Pin       
int const DIO = 4;     // TM1637 Digital I/O Pin
 
TM1637 tm1637(CLK,DIO);   // Create TM1637 object
DHT dht(DHT_PIN, DHT22);  // Create DHT22 sensor object
//===============================================================================
//  Initialization
//===============================================================================
void setup(){
  dht.begin();
  tm1637.init();         // Initialize / clear display
  tm1637.set(3);         // Set brightess (0=dimmest - 7 = brightess)
  delay(1500);           // Delay to let modules initialize
}
//===============================================================================
//  Main
//===============================================================================
void loop(){
 
 float temp = dht.readTemperature(true); // Retrieve temp from sensor in Fahrenheit
 float humidity = dht.readHumidity();    // Retrieve humidity from sensor
 int itemp = (int)temp;                  // Cast floats into integers 
 int ihumidity = (int)humidity;
 int digitoneT = itemp / 10;            // Parse readings into 2 digits to display
 int digittwoT = itemp % 10;
 int digitoneH = ihumidity / 10; 
 int digittwoH = ihumidity % 10;
  
  tm1637.display(1,digitoneT);  // Display temperature
  tm1637.display(2,digittwoT);
  tm1637.display(3,15);         // put a F at the end for 'Fahrenheit'
    
  delay (3000);                // Wait 3 seconds to update display
  
  tm1637.display(1,0x7F);      // Clear leading digit from temp display
  tm1637.display(2,digitoneH); // Display humidity in last 2 digits
  tm1637.display(3,digittwoH);
    
    delay(3000);              //Wait 3 seconds between readings
}

BEFORE THEY ARE SHIPPED, THESE MODULES ARE:

• Sample inspected and tested per incoming shipment.

Notes:  

1. None

TECHNICAL SPECIFICATIONS