T-1 3mm Green LED Luminous Intensity 680-1900mcd - Voltage 2.7-3.8V - Power 108mW - English Technical Document

1. Product Overview

This document details the specifications for a high-performance, green light-emitting diode (LED) in a standard T-1 (3mm) through-hole package. The device is designed for general-purpose indicator and illumination applications where high brightness, low power consumption, and reliable performance are required. Its core advantages include RoHS compliance, high luminous efficiency, and compatibility with low-current drive circuits, making it suitable for a wide range of consumer electronics, industrial controls, and panel indicators.

2. In-Depth Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device's operational limits are defined at an ambient temperature (T_A) of 25°C. The maximum continuous forward current is 30 mA, with a peak forward current of 100 mA permissible under pulsed conditions (1/10 duty cycle, 0.1ms pulse width). The maximum power dissipation is 108 mW. The operating temperature range is from -30°C to +80°C, and the storage temperature range is from -40°C to +100°C. For soldering, leads can withstand 260°C for a maximum of 5 seconds when measured 1.6mm from the LED body.

2.2 Electrical and Optical Characteristics

Key performance parameters are measured at T_A=25°C and a forward current (I_F) of 20 mA. The luminous intensity (I_V) ranges from a minimum of 680 mcd to a typical 1900 mcd. The viewing angle (2θ_1/2) is typically 40 degrees. The device emits green light with a peak emission wavelength (λ_P) of 523 nm and a dominant wavelength (λ_d) ranging from 520 nm to 538 nm. The forward voltage (V_F) is between 2.7V and 3.8V, with a typical value of 3.3V. The reverse current (I_R) is a maximum of 10 μA at a reverse voltage (V_R) of 5V. It is critical to note that the device is not designed for operation under reverse bias; the V_R condition is for I_R testing only.

3. Binning System Specification

The LEDs are classified into bins based on luminous intensity and dominant wavelength to ensure color and brightness consistency in applications.

3.1 Luminous Intensity Binning

Units are in millicandelas (mcd) at 20 mA. Two primary bins are defined: Bin NP (680 mcd to 1150 mcd) and Bin QR (1150 mcd to 1900 mcd). A tolerance of ±15% applies to each bin limit.

3.2 Dominant Wavelength Binning

Units are in nanometers (nm) at 20 mA. Five bins are defined: G10 (520.0-523.0 nm), G11 (523.0-527.0 nm), G12 (527.0-531.0 nm), G13 (531.0-535.0 nm), and G14 (535.0-538.0 nm). A tolerance of ±1 nm applies to each bin limit.

4. Performance Curve Analysis

While specific graphical data is not provided in the text extract, typical performance curves for such LEDs would include the relationship between forward current (I_F) and forward voltage (V_F), showing the diode's exponential characteristic. Another crucial curve would plot luminous intensity (I_V) against forward current (I_F), demonstrating the near-linear relationship within the operating range. The effect of ambient temperature on luminous intensity is also significant, typically showing a decrease in output as temperature increases. The spectral distribution curve would center around the 523 nm peak with a typical half-width (Δλ) of 35 nm, defining the purity of the green color.

5. Mechanical and Package Information

The device uses a popular T-1 (3mm diameter) through-hole package with a white diffused lens. Key dimensional notes include: all dimensions are in millimeters, with a general tolerance of ±0.25mm unless specified otherwise. The maximum protrusion of resin under the flange is 1.0mm. Lead spacing is measured at the point where the leads emerge from the package body. The diffused lens helps in achieving a wider and more uniform viewing angle compared to clear lenses.

6. Soldering and Assembly Guidelines

6.1 Lead Forming and Handling

Lead forming must be performed at normal room temperature and before the soldering process. The bend should be made at least 1.6mm away from the base of the LED lens. The base of the lead frame must not be used as a fulcrum during bending to avoid stress transfer to the internal die and wire bonds. During PCB assembly, minimal clinch force should be used.

6.2 Soldering Process

A minimum clearance of 1.6mm must be maintained between the base of the lens and the solder point. Dipping the lens into solder must be avoided to prevent epoxy climb-up, which can cause soldering issues. Correcting the LED position after soldering is also prohibited. Recommended conditions are:

• Soldering Iron: Temperature 400°C max, time 3 seconds max (one time only).
• Wave Soldering: Pre-heat 120°C max for 60 sec max, solder wave at 260°C max for 5 sec max.

6.3 Storage and Cleaning

For storage outside the original packaging, use within three months is recommended. For extended storage, use a sealed container with desiccant or a nitrogen ambient. If cleaning is necessary, use alcohol-based solvents like isopropyl alcohol.

7. Packaging and Ordering Information

The standard packaging flow is: 1,000 pieces per anti-static packing bag. Ten bags are packed into an inner carton, totaling 10,000 pieces per inner carton. Eight inner cartons are packed into an outer shipping carton, resulting in a total of 80,000 pieces per outer carton. The luminous intensity classification code is marked on each packing bag for traceability.

8. Application Recommendations

8.1 Typical Application Scenarios

This LED is intended for ordinary electronic equipment including office automation devices, communication equipment, and household appliances. Its high brightness makes it suitable for status indicators, backlighting for panels and switches, and decorative lighting where a distinct green signal is required.

8.2 Circuit Design Considerations

LEDs are current-operated devices. To ensure uniform brightness when driving multiple LEDs in parallel, it is strongly recommended to use a current-limiting resistor in series with each LED (Circuit Model A). Driving multiple LEDs in parallel without individual resistors (Circuit Model B) can lead to significant brightness differences due to variances in the forward voltage (V_F) of individual devices. The series resistor value can be calculated using Ohm's Law: R = (V_Supply - V_F) / I_F, where I_F is the desired drive current (e.g., 20mA).

8.3 Precautions for Critical Applications

Consult with the supplier before using this LED in applications requiring exceptional reliability, especially where failure could jeopardize life or health (e.g., aviation, medical systems, safety devices).

9. Electrostatic Discharge (ESD) and Handling Precautions

LEDs are sensitive to electrostatic discharge and voltage surges. It is recommended to use a wrist strap or anti-static gloves when handling. All equipment, including soldering irons and workbenches, must be properly grounded. Avoid applying any mechanical stress to the leads, particularly when the device is heated during soldering.

10. Technical Comparison and Differentiation

This device's key differentiators in its class include its high luminous intensity range (up to 1900 mcd) from a standard T-1 package, offering significant brightness in a common form factor. The use of InGaN (Indium Gallium Nitride) technology provides efficient green emission. The defined binning structure for both intensity and wavelength allows designers to select parts for applications requiring tight color and brightness matching, reducing the need for post-production calibration.

11. Frequently Asked Questions (FAQs)

11.1 Can I drive this LED without a series resistor?

No. Operating an LED directly from a voltage source is not recommended as it is a current-driven device. The small variation in forward voltage can cause a large change in current, potentially exceeding the maximum rating and destroying the LED. A series resistor is essential for stable and safe operation.

11.2 Why is there a range for luminous intensity (680-1900 mcd)?

The range represents the binning structure. Due to manufacturing process variations, LEDs are sorted (binned) after production based on measured performance. The datasheet specifies the minimum and maximum limits for available bins (NP and QR). Designers should account for the ±15% tolerance within a bin when designing for a specific brightness level.

11.3 What is the difference between peak wavelength and dominant wavelength?

Peak wavelength (λ_P) is the wavelength at which the spectral power distribution is maximum (523 nm for this LED). Dominant wavelength (λ_d) is derived from the CIE chromaticity diagram and represents the single wavelength of the monochromatic light that, when combined with a specified white reference, matches the color of the LED. It is the perceptual color. The dominant wavelength range is 520-538 nm.

12. Design and Usage Case Study

Scenario: Designing a multi-indicator status panel for industrial equipment requiring 10 uniformly bright green LEDs. Design Steps: 1. Select LEDs from the same luminous intensity bin (e.g., QR) and a narrow dominant wavelength bin (e.g., G11) for consistency. 2. The power supply is 5V DC. 3. Using the typical V_F of 3.3V and a target I_F of 20 mA, calculate the series resistor: R = (5V - 3.3V) / 0.02A = 85 Ohms. A standard 82 Ohm or 100 Ohm resistor can be used, slightly adjusting the current. 4. Implement Circuit Model A, using one resistor per LED. 5. During PCB layout, ensure the recommended 1.6mm clearance between the LED body and solder pad. 6. Follow the wave soldering profile precisely. This approach ensures reliable operation and uniform appearance.

13. Operating Principle Introduction

A Light Emitting Diode (LED) is a semiconductor p-n junction diode. When a forward voltage is applied, electrons from the n-type region and holes from the p-type region are injected into the junction region. When these charge carriers recombine, energy is released in the form of photons (light). The color (wavelength) of the emitted light is determined by the energy bandgap of the semiconductor material. This specific LED uses an InGaN (Indium Gallium Nitride) compound semiconductor, which is engineered to have a bandgap corresponding to green light emission.

14. Technology Trends

The LED industry continues to advance in efficiency (lumens per watt), allowing for higher brightness at lower power consumption. There is a trend towards tighter binning tolerances for both color and flux to meet the demands of applications like full-color displays and architectural lighting where consistency is paramount. While through-hole packages like the T-1 remain popular for prototyping, hobbyist use, and certain industrial applications, surface-mount device (SMD) packages dominate high-volume production due to their smaller size and suitability for automated assembly. The underlying InGaN technology for green and blue LEDs is mature but continues to see incremental improvements in efficiency and reliability.