The 5mm IR Infrared Transmitter LED (940nm) is the standard light source for wireless optical communication. At Electrapac, we recommend this high-output transmitter for building custom remote controls, IR "invisible" security illuminators, or obstacle-detection sensors for robotics.

Product Overview

This transmitter is a high-efficiency Infrared Emitting Diode. Unlike standard LEDs, it emits light in the 940nm wavelength, which is completely invisible to the human eye but easily detected by IR receivers and many camera sensors. Designed for high-speed switching, it is perfectly suited for sending complex binary codes (like NEC or Sony protocols) through the air.

Key Features for Electrapac Customers

• Invisible Operation: Perfect for discreet signaling or security applications where you don't want a visible "red glow."

• High Pulsed Power: While rated for 20mA continuous use, these LEDs can handle high-current pulses (via a transistor), allowing you to project a signal across large rooms (up to 10+ meters).

• Narrow Beam Angle: The 5mm lens acts as a natural concentrator, creating a directional beam that ensures your signal reaches the receiver with minimal scatter.

• Standard 5mm Footprint: Fits into all standard LED holders and breadboards, making it easy to incorporate into Electrapac project boxes.

• Fast Response Time: Capable of switching on and off in nanoseconds, which is essential for carrying high-frequency data.

Technical Implementation Guide

To maximize the range and lifespan of your Electrapac IR transmitter, follow these design tips:

1. Use a Transistor Driver: Microcontroller pins (like those on an Arduino) often cannot provide enough current for a long-range IR beam. Use a 2N2222 or BC547 transistor to drive the LED at higher pulse currents.

2. Current Limiting Resistor: With a forward voltage of only 1.2V, you must use a resistor. For a 5V supply at 20mA, use a 220Ω resistor. For high-power pulses, calculate accordingly.

3. Polarity: Like all LEDs, the longer lead is the Anode (+) and the shorter lead (near the flat side of the casing) is the Cathode (-).

4. Testing Tip: Since the light is invisible, you can check if the LED is working by looking at it through a digital smartphone camera; it will appear as a faint purple or white light on the screen.

Primary Applications

• Custom Remote Controls: Creating a universal remote to control TVs, Air Conditioners, or Stereos.

• IR Break-Beam Sensors: Using a transmitter and receiver pair to detect objects passing through a doorway or on a conveyor belt.

• Proximity Sensing: Building simple obstacle-avoidance systems for mobile robots.

• Wireless Data Links: Sending low-speed data between two isolated circuits without physical wires.

• Night Vision Illumination: Providing a small amount of invisible light for IR-sensitive security cameras.

Why Shop at Electrapac?

We source our 940nm IR LEDs for peak spectral purity, ensuring they match perfectly with standard 38kHz IR receivers. Visit us at for the wireless components that keep your projects connected.