6.2mm Round Through Hole LED Lamp LTL30SETG3JA - Red 625nm / Green 530nm - 20mA - 125mW - English Technical Document

1. Product Overview

This document details the specifications for a 6.2mm round through-hole LED lamp, identified by part number LTL30SETG3JA. The device is designed as a high-brightness indicator light source suitable for various signage applications. It utilizes two distinct semiconductor technologies: AlGaInP for the red emitter and InGaN for the green emitter, each offering specific wavelength characteristics.

1.1 Core Advantages

The primary advantages of this LED lamp include its high luminous intensity output, which enables excellent visibility. It features low power consumption coupled with high luminous efficiency, contributing to energy savings. The package is constructed using advanced epoxy technology that provides superior moisture resistance and incorporates UV inhibitors, enhancing its durability and reliability for long-term use in both indoor and outdoor environments. The product is lead-free and compliant with RoHS directives.

1.2 Target Market and Applications

The uniform radiation pattern and high brightness make this LED ideal for applications requiring clear, long-distance visibility. Primary target applications include traffic signal signboards, large-format billboards, dynamic message signs, and signage on public transportation vehicles such as buses.

2. In-Depth Technical Parameter Analysis

This section provides a detailed breakdown of the electrical, optical, and thermal parameters that define the operational boundaries and performance of the LED.

2.1 Absolute Maximum Ratings

These ratings specify the limits beyond which permanent damage to the device may occur. They are defined at an ambient temperature (TA) of 25°C. The maximum continuous power dissipation is 125 mW for the red chip and 112 mW for the green chip. The maximum DC forward current is 50 mA for red and 30 mA for green. For pulsed operation (duty cycle ≤ 1/10, pulse width ≤ 10ms), a peak forward current of 100 mA is allowed for both colors. The maximum reverse voltage is 5 V. The device can operate within an ambient temperature range of -30°C to +85°C and be stored from -40°C to +100°C. The leads can withstand soldering at 260°C for a maximum of 5 seconds, provided the soldering point is at least 2.0mm from the LED body.

2.2 Electrical and Optical Characteristics

These characteristics are measured under standard test conditions (TA=25°C, IF=20mA) and represent typical performance. The luminous intensity (Iv) for the red LED has a typical value of 4200 mcd (min 1500 mcd), while the green LED has a typical value of 6900 mcd (min 3000 mcd). The viewing angle (2θ1/2) for both colors is 30 degrees with a ±2-degree tolerance. The peak emission wavelength (λP) is typically 627 nm for red and 525 nm for green. The dominant wavelength (λd) ranges from 620-630 nm for red and 525-535 nm for green. The forward voltage (VF) is typically 2.5 V for red (max 3.2 V) and 3.75 V for green (max 4.5 V). The reverse current (IR) is a maximum of 100 µA at VR=5V.

2.3 Thermal Characteristics

Thermal management is crucial for LED longevity. The derating factor for the DC forward current is specified. For the red LED, the current must be reduced linearly by 0.84 mA for every degree Celsius above 50°C. For the green LED, the derating is 0.36 mA/°C above 50°C. This ensures the junction temperature remains within safe limits, preventing accelerated degradation or catastrophic failure.

3. Binning System Specification

To ensure color and brightness consistency in production, the LEDs are sorted into bins based on luminous intensity and dominant wavelength.

3.1 Luminous Intensity Binning

The intensity binning table categorizes LEDs using a two-character code (e.g., UR, VS, WU). The first letter (U, V, W) defines the green luminous intensity range: U (3000-4000 mcd), V (4000-5300 mcd), W (5300-6900 mcd). The second letter (R, S, T, U) defines the red luminous intensity range: R (1500-1900 mcd), S (1900-2500 mcd), T (2500-3200 mcd), U (3200-4200 mcd). A tolerance of ±15% applies to each bin limit.

3.2 Hue (Wavelength) Binning

For the green LED, a separate hue binning is provided. Bin code G1 covers a dominant wavelength range of 525-530 nm, and G2 covers 530-535 nm. The tolerance for each bin limit is ±1 nm. This allows designers to select LEDs with very specific color points if required for their application.

4. Performance Curve Analysis

While specific graphical curves are referenced in the datasheet (Fig.1, Fig.6), their typical implications are analyzed here. The forward current vs. forward voltage (I-V) curve is non-linear, characteristic of a diode. The luminous intensity is approximately proportional to the forward current within the recommended operating range. The spectral distribution curve shows the relative radiant power as a function of wavelength, with the peak and dominant wavelengths identified. The viewing angle diagram illustrates the spatial radiation pattern, confirming the 30-degree half-intensity angle.

5. Mechanical and Packaging Information

5.1 Outline Dimensions

The LED features a standard 6.2mm diameter round lens. Key dimensional notes include: all dimensions are in millimeters (inches); standard tolerance is ±0.25mm unless specified; the maximum protrusion of resin under the flange is 1.0mm; lead spacing is measured at the point where leads exit the package body. The polarity is indicated by the longer anode (+) lead and/or a flat spot on the lens rim near the cathode (-) lead.

5.2 Packaging Specifications

The LEDs are supplied in packing bags containing 500, 200, or 100 pieces. Ten of these bags are packed into an inner carton, totaling 5,000 pieces. Eight inner cartons are packed into an outer shipping carton, totaling 40,000 pieces. In any shipping lot, only the final pack may contain a non-full quantity.

6. Soldering and Assembly Guidelines

Proper handling is critical to prevent damage. Leads must be formed at a point at least 3mm from the base of the LED lens before soldering, and the lens base should not be used as a fulcrum. During PCB assembly, minimal clinch force should be used. For soldering, maintain a minimum clearance of 3mm (for iron) or 2mm (for wave) between the solder point and the lens base. Do not immerse the lens in solder. Recommended soldering conditions: Soldering iron temperature max 350°C for max 3 seconds (one time only). Wave soldering: pre-heat max 100°C for 60s max, solder wave max 260°C for 5s max. Infrared (IR) reflow is not suitable for this through-hole product. Excessive heat or time can deform the lens or destroy the LED.

7. Application Recommendations and Design Considerations

7.1 Drive Circuit Design

LEDs are current-operated devices. To ensure uniform brightness when connecting multiple LEDs in parallel, it is strongly recommended to use a individual current-limiting resistor in series with each LED (Circuit A). Connecting LEDs directly in parallel without individual resistors (Circuit B) is not recommended, as slight variations in the forward voltage (Vf) characteristic between individual LEDs will cause significant differences in current sharing and, consequently, brightness.

7.2 Electrostatic Discharge (ESD) Protection

The LED is susceptible to damage from electrostatic discharge or power surges. Appropriate ESD prevention measures should be implemented in the handling and assembly environment, such as the use of grounded workstations, wrist straps, and conductive flooring.

7.3 Storage and Cleaning

For storage, the ambient should not exceed 30°C or 70% relative humidity. LEDs removed from their original packaging should be used within three months. For longer storage outside the original pack, use a sealed container with desiccant or a nitrogen desiccator. If cleaning is necessary, use alcohol-based solvents like isopropyl alcohol.

8. Technical Comparison and Differentiation

Compared to generic 5mm LEDs, this 6.2mm lamp offers significantly higher luminous intensity, making it suitable for applications requiring longer viewing distances or brighter indications. The use of AlGaInP for red provides high efficiency and excellent color purity in the red-orange spectrum. The InGaN green chip offers high brightness. The integrated diffused white lens provides a uniform viewing angle, unlike clear lenses which can have a more focused beam. The enhanced epoxy with UV inhibitor specifically targets outdoor durability, a key differentiator from standard indoor-grade LEDs.

9. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED at 30mA continuously?
A: For the red LED, yes, as its max DC current is 50mA. For the green LED, 30mA is the absolute maximum DC rating; continuous operation at this level without proper thermal derating may reduce lifespan. Operating at the typical 20mA is recommended for both.

Q: What resistor value should I use for a 12V supply?
A: Using Ohm's Law: R = (Vsupply - Vf_LED) / I_LED. For a green LED (Vf~3.75V) at 20mA: R = (12 - 3.75) / 0.02 = 412.5 Ohms. Use the nearest standard value (e.g., 390 or 430 Ohms) and calculate the power rating of the resistor: P = I^2 * R.

Q: Is this LED suitable for battery-powered devices?
A: Yes, its high luminous efficiency (high mcd/mA) makes it suitable for battery-powered applications where power consumption is a concern, especially when driven at or below 20mA.

10. Practical Application Case Study

Scenario: Designing a \"Bus Stop\" illuminated sign for outdoor use.
Design Considerations: The sign must be clearly visible day and night. Using the green LEDs (Bin W for highest brightness) for the text would provide high contrast. The 30-degree viewing angle ensures the sign is readable from a wide approach angle. The LEDs must be driven with individual current-limiting resistors connected to a constant-voltage power supply, with the resistor values calculated based on the supply voltage and the typical Vf of the green LED. The PCB design must maintain the minimum 2-3mm clearance between the solder pad and the LED body as per the soldering guidelines. The UV-resistant epoxy ensures the lens does not yellow or degrade over years of sun exposure, maintaining light output and color.

11. Operating Principle Introduction

Light Emitting Diodes (LEDs) are semiconductor devices that emit light when an electric current passes through them. This phenomenon is called electroluminescence. In an LED, electrons recombine with holes within the semiconductor material (AlGaInP for red, InGaN for green), releasing energy in the form of photons. The specific wavelength (color) of the light is determined by the energy bandgap of the semiconductor material. The epoxy lens serves to protect the semiconductor chip, shape the radiation pattern (30-degree viewing angle in this case), and in this product, incorporates a diffuser to create a uniform appearance.

12. Technology Trends

The general trend in LED technology is toward higher efficacy (more lumens per watt), improved color rendering, and lower cost. For indicator-type LEDs like this one, trends include miniaturization (smaller packages with similar output), integration of multiple chips (RGB) into a single package, and the development of more robust packaging materials for extreme environments. The underlying material science for red (AlGaInP) and green/blue (InGaN) LEDs continues to mature, leading to incremental improvements in efficiency and lifetime. The drive for energy efficiency across all electronic devices continues to favor LED technology over traditional incandescent or neon indicators.