LED Component Datasheet - Lifecycle Revision 2 - Release Date 2014-12-05 - English Technical Document

1. Product Overview

This technical document provides comprehensive specifications and guidelines for a light-emitting diode (LED) component. The core advantage of this component lies in its standardized design and reliable performance, making it suitable for a wide range of general illumination and indicator applications. The target market includes consumer electronics, automotive lighting, signage, and industrial control systems where consistent light output and long-term reliability are paramount. The document reflects a specific lifecycle phase of Revision 2, indicating an update or refinement from a previous version, with a release date of December 5, 2014. The 'Expired Period: Forever' designation suggests this revision is intended to be the definitive and final specification for this particular product version, superseding all prior documents.

2. In-Depth Technical Parameter Analysis

While the provided excerpt focuses on document metadata, a complete datasheet for an LED component would typically include the following detailed technical parameters. This section provides an objective interpretation of such standard parameters.

2.1 Photometric and Color Characteristics

Key photometric parameters define the light output and quality. Luminous flux, measured in lumens (lm), indicates the total perceived power of light emitted. Color temperature, measured in Kelvin (K), describes the hue of white light, ranging from warm white (2700K-3500K) to cool white (5000K-6500K). Chromaticity coordinates (e.g., CIE 1931 x, y) precisely define the color point on a standard color space diagram. Color Rendering Index (CRI), a scale from 0 to 100, measures the ability of the light source to reveal the colors of objects faithfully compared to a natural light source. A higher CRI (typically Ra>80) is desirable for applications requiring accurate color perception.

2.2 Electrical Parameters

The electrical characteristics are critical for circuit design. The forward voltage (Vf) is the voltage drop across the LED when operating at its specified current. It varies with the semiconductor material (e.g., InGaN for blue/white, AlInGaP for red/amber). The typical forward current (If) is the recommended operating current for achieving rated performance and longevity. Maximum ratings for reverse voltage (Vr), forward current, and power dissipation must not be exceeded to prevent permanent damage. The dynamic resistance can be derived from the IV curve and is important for driver design.

2.3 Thermal Characteristics

LED performance and lifespan are heavily influenced by temperature. The junction temperature (Tj) is the temperature at the semiconductor chip itself. The thermal resistance (Rth_j-a or Rth_j-c), measured in °C/W, quantifies the difficulty of heat transfer from the junction to the ambient air or case. A lower thermal resistance indicates better heat dissipation. The maximum allowable junction temperature (Tj_max) is the absolute limit; operating below this temperature is essential for reliability. Proper heatsinking is required to maintain Tj within safe limits, especially for high-power LEDs.

3. Binning System Explanation

Manufacturing variations necessitate a binning system to ensure consistency. LEDs are sorted into bins based on key parameters measured after production.

3.1 Wavelength/Color Temperature Binning

LEDs are grouped into tight wavelength ranges (e.g., +/- 2nm) or color temperature bins (e.g., 3-step, 5-step MacAdam ellipses) to ensure color uniformity in an array or fixture. This is crucial for applications where color matching is important.

3.2 Luminous Flux Binning

LEDs are sorted based on their measured light output at a standard test current. Common bins are defined by a minimum luminous flux value (e.g., Bin L: 100-110 lm, Bin M: 110-120 lm). This allows designers to select components that meet specific brightness requirements.

3.3 Forward Voltage Binning

Sorting by forward voltage (Vf) helps in designing efficient driver circuits, especially when connecting multiple LEDs in series. Matching Vf bins can lead to more uniform current distribution and simplified driver design.

4. Performance Curve Analysis

Graphical data provides deeper insight into component behavior under varying conditions.

4.1 Current-Voltage (I-V) Characteristic Curve

The I-V curve shows the nonlinear relationship between forward current and voltage. It demonstrates the turn-on voltage and the dynamic resistance in the operating region. This curve is fundamental for selecting an appropriate current-limiting driver.

4.2 Temperature Dependency

Graphs typically show how forward voltage decreases and luminous flux degrades as junction temperature increases. Understanding this relationship is key to thermal management and predicting performance in real-world operating environments.

4.3 Spectral Power Distribution (SPD)

The SPD graph plots radiant power versus wavelength. For white LEDs (often blue chip + phosphor), it shows the blue peak from the chip and the broader yellow phosphor emission. The SPD determines the color temperature and CRI of the LED.

5. Mechanical and Packaging Information

Physical specifications ensure proper integration into the final product.

5.1 Dimensional Outline Drawing

A detailed drawing provides exact dimensions including length, width, height, and any critical tolerances. It specifies the location of the optical center and mechanical reference points.

5.2 Pad Layout and Solder Pad Design

The recommended footprint for PCB layout is provided, including pad size, shape, and spacing. This is essential for achieving reliable solder joints and proper thermal connection to the PCB.

5.3 Polarity Identification

Clear markings indicate the anode and cathode. Common indicators include a notch, a dot, a beveled corner, or different lead lengths. Correct polarity is mandatory for operation.

6. Soldering and Assembly Guidelines

Proper handling ensures reliability and prevents damage during manufacturing.

6.1 Reflow Soldering Profile

A recommended temperature profile is provided, including preheat, soak, reflow peak temperature (typically not exceeding 260°C for a short time), and cooling rates. Adherence prevents thermal shock and solder joint defects.

6.2 Precautions and Handling

Guidelines cover ESD (Electrostatic Discharge) protection, as LEDs are sensitive to static electricity. Recommendations for storage conditions (temperature, humidity) and shelf life are also included. Avoid mechanical stress on the lens or leads.

6.3 Storage Conditions

LEDs should be stored in a dry, dark environment within specified temperature and humidity ranges. Moisture-sensitive devices may require baking before use if the packaging has been opened and exposed to ambient humidity for too long.

7. Packaging and Ordering Information

This section details how the product is supplied and how to specify it.

7.1 Packaging Specifications

Describes the packaging format, such as tape-and-reel dimensions, reel quantity, or tray specifications. This information is vital for automated pick-and-place assembly equipment.

7.2 Labeling Information

Explains the markings on the reel or box label, which typically include part number, quantity, lot number, date code, and bin codes for key parameters.

7.3 Part Numbering System

Decodes the part number structure, showing how different codes within the part number correspond to specific attributes like color, flux bin, voltage bin, color temperature, and packaging type.

8. Application Recommendations

Guidance on implementing the component effectively.

8.1 Typical Application Circuits

Schematics for basic drive circuits, such as using a series resistor with a constant voltage source or employing a constant current LED driver IC. The importance of current regulation over voltage regulation is emphasized.

8.2 Design Considerations

Key points include thermal management (PCB copper area, vias, heatsinks), optical design (lens selection, beam angle), and electrical design (driver selection, dimming method, protection against transients and reverse polarity).

9. Technical Comparison

An objective comparison highlights the positioning of this component. Compared to earlier revisions or alternative technologies, this Revision 2 component may offer improvements in luminous efficacy (lumens per watt), tighter color consistency, enhanced reliability under thermal stress, or a more robust package design. The 'Forever' expired period suggests it represents a mature, stable product specification.

10. Frequently Asked Questions (FAQ)

Answers to common queries based on technical parameters.

Q: What does 'LifecyclePhase: Revision 2' mean?
A: It indicates this is the second major revision of the product's technical documentation, incorporating updates, corrections, or specification changes from the initial release.

Q: Why is the 'Expired Period' listed as 'Forever'?
A: This denotes that this revision of the datasheet does not have a planned obsolescence date and is intended to be the valid reference document indefinitely, unless superseded by a new revision.

Q: How should I interpret the release date in the context of product selection?
A: The release date (2014-12-05) indicates when this document version was published. For the latest product status, availability, or potential newer revisions, consulting the manufacturer's official channels is recommended.

11. Practical Use Cases

Based on typical specifications for a component with this document structure, practical applications include: Backlighting for LCD displays in monitors and TVs, requiring uniform brightness and color. Architectural accent lighting, where consistent color temperature across multiple fixtures is critical. Automotive interior lighting (dome lights, dashboard indicators), demanding reliability across a wide temperature range. Consumer appliance status indicators, benefiting from long life and low power consumption.

12. Operating Principle Introduction

An LED is a semiconductor diode. When a forward voltage is applied, electrons from the n-type material recombine with holes from the p-type material in the active region, releasing energy in the form of photons (light). The wavelength (color) of the emitted light is determined by the energy bandgap of the semiconductor material used (e.g., Gallium Nitride for blue, Gallium Arsenide Phosphide for red). White LEDs are typically created by coating a blue LED chip with a yellow phosphor; the mixture of blue and yellow light is perceived as white.

13. Technology Trends

The LED industry continues to evolve. Trends observable around the time of this document's release (2014) and beyond include: Continuous improvement in luminous efficacy, reducing energy consumption for the same light output. Development of higher Color Rendering Index (CRI) LEDs for superior light quality. Miniaturization of packages while maintaining or increasing light output. Advancements in color mixing and tunable white systems for dynamic lighting. Increased integration of control electronics and sensors into LED modules. The shift towards standardized communication protocols like DALI and Zhaga for connected lighting systems. The progression from document Revision 1 to Revision 2 itself is a microcosm of this iterative improvement process.