3mm Infrared LED IR204/H16/L10 Datasheet - Dimensions 3mm - Voltage 1.5V - Wavelength 940nm - English Technical Document

1. Product Overview

This document details the specifications for a high-intensity 3mm (T-1) infrared light-emitting diode (LED). The device is housed in a blue transparent plastic package and is engineered for optimal spectral matching with silicon photodetectors, phototransistors, and infrared receiver modules. Its primary function is to emit infrared light at a peak wavelength of 940 nanometers, making it invisible to the human eye while being highly detectable by electronic sensors.

1.1 Core Advantages and Target Market

The LED offers several key advantages including high reliability, low forward voltage, and high radiant intensity. It is designed with a standard 2.54mm lead spacing for easy PCB integration. The product is compliant with RoHS, EU REACH, and halogen-free standards (Br < 900ppm, Cl < 900ppm, Br+Cl < 1500ppm), making it suitable for environmentally conscious and regulated markets. Its primary target applications are in infrared-based systems such as remote controls, proximity sensors, object detection, and optical switches.

2. In-Depth Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device is designed to operate within strict limits to ensure longevity and reliability. The continuous forward current (IF) must not exceed 100 mA. For pulsed operation with a pulse width ≤100μs and duty cycle ≤1%, a peak forward current (IFP) of up to 1.0 A is permissible. The maximum reverse voltage (VR) is 5 V. The operating temperature range (Topr) is from -40°C to +85°C, while the storage temperature (Tstg) extends from -40°C to +100°C. The soldering temperature (Tsol) must be kept at or below 260°C for a duration not exceeding 5 seconds. The maximum power dissipation (Pd) at 25°C free air temperature is 150 mW.

2.2 Electro-Optical Characteristics

All electro-optical characteristics are specified at an ambient temperature (Ta) of 25°C and a forward current (IF) of 20mA, unless otherwise noted. The radiant intensity (IE) is binned, with minimum values ranging from 4.0 to 11.0 mW/sr depending on the rank. The peak wavelength (λp) is typically 940 nm, with a spectral bandwidth (Δλ) of 45 nm. The forward voltage (VF) is typically 1.2 V with a maximum of 1.5 V. The reverse current (IR) is a maximum of 10 μA at a reverse voltage of 5V. The viewing angle (2θ1/2), defined as the full angle at half intensity, is typically 50 degrees.

3. Binning System Explanation

The radiant output of the LED is categorized into bins to ensure consistency in application design. The binning is based on radiant intensity measured at IF=20mA. The available bins are K, L, M, and N, with corresponding minimum and maximum radiant intensity values as follows: Bin K: 4.0-6.4 mW/sr; Bin L: 5.6-8.9 mW/sr; Bin M: 7.8-12.5 mW/sr; Bin N: 11.0-17.6 mW/sr. This allows designers to select a component that meets the specific sensitivity requirements of their photodetector circuit.

4. Performance Curve Analysis

4.1 Forward Current vs. Ambient Temperature

The derating curve shows the relationship between the maximum allowable continuous forward current and the ambient temperature. As the ambient temperature increases, the maximum permissible forward current decreases linearly. This is a critical design consideration to prevent thermal runaway and ensure the junction temperature remains within safe operating limits, thereby maintaining device reliability.

4.2 Spectral Distribution

The spectral distribution graph illustrates the relative radiant intensity as a function of wavelength. The emission is centered around the typical peak wavelength of 940 nm with a defined bandwidth. This characteristic is crucial for ensuring compatibility with the receiving sensor, which typically has its own spectral sensitivity curve. A good match maximizes system efficiency and signal-to-noise ratio.

4.3 Radiant Intensity vs. Forward Current

This graph depicts the non-linear relationship between radiant output (Ie) and forward current (IF). The radiant intensity increases with current but not in a perfectly linear fashion, especially at higher current levels. Understanding this curve is essential for driving the LED correctly to achieve the desired optical output without exceeding absolute maximum ratings.

4.4 Relative Radiant Intensity vs. Angular Displacement

The radiation pattern graph shows how the emitted light intensity varies with the angle from the central axis (0°). The pattern is typically Lambertian or near-Lambertian for this package type, with intensity dropping to 50% of its on-axis value at approximately ±25 degrees (resulting in the 50° viewing angle). This information is vital for optical design, determining the coverage area and alignment requirements in a system.

5. Mechanical and Package Information

The LED is packaged in a standard T-1 (3mm) radial leaded package. The body is made of blue transparent plastic. The leads have a standard spacing of 2.54mm (0.1 inches). The dimensional drawing (implied in the PDF) would provide exact measurements for the body diameter, lead length, and other critical dimensions, typically with a tolerance of ±0.25mm unless otherwise specified. The cathode is typically identified by a flat spot on the lens rim or a shorter lead, though the specific marking should be verified from the mechanical drawing.

6. Soldering and Assembly Guidelines

Hand soldering or wave soldering processes can be used. The absolute maximum soldering temperature is 260°C, and the soldering time should not exceed 5 seconds. It is recommended to follow standard IPC guidelines for through-hole component soldering. Prolonged exposure to high temperatures can damage the plastic package and the internal semiconductor die. The device should be stored in a dry environment to prevent moisture absorption, which could cause popcorning during reflow if applicable, though this is primarily a through-hole component.

7. Packaging and Ordering Information

The standard packing specification is 200 to 1000 pieces per bag, 4 bags per box, and 10 boxes per carton. The label on the packaging includes critical information for traceability and identification: Customer's Production Number (CPN), Production Number (P/N), Packing Quantity (QTY), Ranks (CAT), Peak Wavelength (HUE), Reference (REF), Lot Number (LOT No), and Production Place. Moisture-resistant packing materials are used to protect the components during storage and transit.

8. Application Recommendations

8.1 Typical Application Scenarios

This infrared LED is ideally suited for a wide range of non-contact sensing and signaling applications. Common uses include infrared remote controls for consumer electronics (TVs, audio systems), proximity and object detection in appliances and industrial equipment, optical encoders, beam-break sensors, and as a light source in paired emitter-detector modules for counting or level sensing.

8.2 Design Considerations

When designing a circuit, always include a current-limiting resistor in series with the LED to control the forward current and prevent damage. The value can be calculated using Ohm's Law: R = (Vsupply - VF) / IF. Choose the appropriate radiant intensity bin based on the required sensing distance and the sensitivity of the detector. Consider the viewing angle when aligning the LED with the receiver. For pulsed operation to achieve higher instantaneous output (e.g., for longer range), ensure the pulse width and duty cycle stay within the specified limits for IFP. Provide adequate PCB layout to dissipate heat, especially when operating near maximum ratings.

9. Technical Comparison and Differentiation

Compared to generic infrared LEDs, this device offers a well-defined and consistent spectral output centered at 940nm, which is a common peak sensitivity wavelength for silicon photodiodes and phototransistors, ensuring efficient coupling. The availability of radiant intensity bins allows for predictable performance in volume production. The combination of low forward voltage (typically 1.2V) and high radiant intensity can lead to more power-efficient designs. Compliance with modern environmental standards (RoHS, REACH, Halogen-Free) is a significant advantage for products targeting global markets with strict regulations.

10. Frequently Asked Questions (FAQs)

Q: What is the difference between the bins K, L, M, and N?
A: The bins represent different ranges of minimum radiant intensity. Bin N has the highest output (11.0-17.6 mW/sr), while Bin K has the lowest (4.0-6.4 mW/sr). Select a bin based on the required signal strength for your application.

Q: Can I drive this LED with a 5V supply directly?
A: No. The forward voltage is only about 1.2-1.5V. Connecting it directly to 5V would cause excessive current flow and destroy the LED. You must always use a series current-limiting resistor.

Q: How do I identify the cathode?
A: For a standard T-1 package, the cathode is usually indicated by a flat edge on the plastic lens rim. Alternatively, when viewing the LED from the bottom, the lead corresponding to the flat side is the cathode. The cathode may also be the shorter lead.

Q: What is the typical operating lifetime?
A: While not explicitly stated in this datasheet, infrared LEDs like this typically have very long operational lifetimes (tens of thousands of hours) when operated within their specified absolute maximum ratings, particularly the current and temperature limits.

11. Practical Use Case Example

Scenario: Designing a Simple Object Detection Sensor.
An engineer needs to detect the presence of an object passing through a gap. They pair this IR204 LED with a phototransistor placed on the opposite side of the gap (through-beam configuration). They select an LED from Bin M for sufficient intensity. The LED is driven with a 20mA constant current from a 3.3V microcontroller pin via a 100Ω resistor (R = (3.3V - 1.2V) / 0.02A ≈ 105Ω). The phototransistor's collector is pulled up to 3.3V through a resistor, and the voltage at the collector is read by the microcontroller's ADC. When the beam is unobstructed, the phototransistor conducts, pulling the voltage low. When an object blocks the beam, the phototransistor stops conducting, and the voltage goes high, signaling the object's presence. The 50° viewing angle ensures a wide enough beam for reliable detection even with slight misalignment.

12. Operating Principle Introduction

An infrared LED is a semiconductor p-n junction diode. When a forward voltage exceeding its bandgap energy is applied, electrons from the n-region recombine with holes from the p-region in the active region (made of GaAlAs in this case). This recombination process releases energy in the form of photons (light). The specific material composition (Gallium Aluminum Arsenide) determines the wavelength of the emitted photons, which in this device is in the infrared spectrum around 940 nm. The blue transparent plastic package is not a filter but acts as a lens to shape the output beam and protect the semiconductor chip.

13. Technology Trends

Infrared LED technology continues to evolve towards higher efficiency (more radiant output per electrical watt input), higher power densities for longer-range applications like LiDAR and time-of-flight sensing, and smaller package sizes for integration into compact consumer devices. There is also a trend towards more precise wavelength control and narrower spectral bandwidths for specific sensing applications, such as gas detection or physiological monitoring. The integration of drivers and control logic directly with the LED die (smart LEDs) is another area of development. The foundational principles of devices like the one described here remain critical for a vast array of established and emerging optoelectronic systems.