IR Emitter Module

Module emits infrared (IR) as is commonly used for creating an IR remote control or IR intrusion sensor.

DESCRIPTION

The IR Emitter Module emits infrared (IR) as is commonly used for creating an IR remote control or IR intrusion sensor.

PACKAGE INCLUDES:

• IR Emitter Module

KEY FEATURES OF IR EMITTER MODULE:

• 850 nm nominal wavelength
• 3.3 and 5V compatible

Infrared is the light spectrum up around 850 nm that is commonly used for IR remotes and is outside the visible spectrum for the human eye.

The module is easy to use.  Hook up ground, then apply a logic HIGH to the ‘S’ input pin, to activate the LED.  The input pin does need a series current limiting resistor to avoid possible damage to the device or any MCU being used to drive it.  A resistance of approximately 220 ohm for 5V or 120 ohm for 3.3V operation should work OK.  The center pin is not used.

Unfortunately, since the IR light is not visible to the human eye, it will appear that the module is doing nothing so you will need something that is sensitive to IR light to detect that the module is actually operating.  The camera on a cell phone is more sensitive to IR light, so if you view the module through your phone camera, you should be able to see it operating and it will have a pinkish/purple glow.  You can of course also use our IR Receiver module for detecting the IR as well.

The IR is typically pulsed at a modulated rate of 38kHz to created coded messages when it is being used as an IR remote control for something like a TV.  Different manufacturers have different transmission protocols for these coded messages.  There is a library that can be used with Arduino called IRRemote if you are looking to create a standard remote control.

The IR emitter can also be used as part of an emitter / detector pair where an object is detected if it breaks the beam between the two.  In this case, the IR emitter is driven on all the time rather than being pulsed.

Module Connections

There is a 3-pin header on the assembly for connections.  The center pin is generally not use.  Some modules may have a 10K resistor that connects the center pin to the ‘S’ pin that might find a use in some applications.

1 x 3 Header 

• ‘-‘ = Ground
• Center pin = No connection
• S = Signal input connects to a digital output pin on uC with a current limiting resistor in series

OUR EVALUATION RESULTS:

These modules are very useful for adding IR capability to a project including everything from making a custom IR remote for your TV to creating a custom serial IR communication link for a robot project or to make an intrusion detector if the IR signal is blocked.  If you need a receiver for use with the transmitter, you will also want to pick up something like our IR Receiver module down below.

The program below does nothing useful, it just pulses the module 50 times each second to test basic operation of the module.  Be sure to use a current limiting resistor on the digital pin.  Operation of the module can be verified by looking at it through a cell phone camera.

IR Emitter Module Test Program

/*
IR Emitter Module Test

Basic code to pulse the IR emitter 
*/

int IRModulePin = 7;  // Random digital pin for toggling the IR emitter

//===============================================================================
//  Initialization
//===============================================================================
void setup() 
{ 
  pinMode(IRModulePin, OUTPUT);  // Set pin as output
}
//===============================================================================
//  Main
//===============================================================================
void loop() 
{
  for(int i=0; i < 50; i++)  //Send burst of 50 pulses every second
  {
    digitalWrite (IRModulePin, HIGH);
    delay(1);
    digitalWrite (IRModulePin, LOW);
    delay(1);
  }
  delay(1000);
}

BEFORE THEY ARE SHIPPED, THESE MODULES ARE:

• Inspected
• Basic output verified
• Packaged in a resealable ESD bag for protection and easy storage.

Notes: 

1. This module is the same or similar to the KY-005

TECHNICAL SPECIFICATIONS