LED Component Datasheet - Lifecycle Revision 3 - Release Date 2014-12-16 - English Technical Document

1. Product Overview

This technical datasheet provides comprehensive specifications and application guidelines for a specific LED component. The document is currently in its third revision (Revision 3), indicating a mature and stable product design with refinements based on field performance and manufacturing feedback. The release date for this revision is documented as December 16, 2014, at 13:32:53. The lifecycle phase is marked as "Revision," and the expired period is noted as "Forever," suggesting this is a final, non-expiring version of the datasheet intended for long-term reference. The component is designed for reliability and consistent performance in various electronic applications.

The core advantage of this component lies in its documented stability and the formalized revision control, which provides engineers with a reliable reference for design-in. The target market includes general lighting, consumer electronics, automotive interior lighting, and indicator applications where consistent luminous output and long-term reliability are paramount.

2. In-Depth Technical Parameter Analysis

While the provided excerpt focuses on document metadata, a complete LED datasheet typically contains detailed technical parameters. The following sections outline the critical parameters that would be essential for design engineers, based on standard industry practices for such components.

2.1 Photometric and Color Characteristics

The photometric characteristics define the light output and quality. Key parameters include luminous flux, measured in lumens (lm), which indicates the total perceived power of light emitted. The correlated color temperature (CCT), measured in Kelvin (K), specifies whether the light appears warm, neutral, or cool white. For colored LEDs, the dominant wavelength and color purity are critical. Chromaticity coordinates (e.g., on the CIE 1931 diagram) provide a precise definition of the emitted color. The viewing angle, typically given as the angle at which luminous intensity drops to half of its maximum value, determines the spatial distribution of light.

2.2 Electrical Parameters

Electrical specifications are fundamental for circuit design. The forward voltage (Vf) is the voltage drop across the LED when operating at a specified forward current (If). This parameter has a typical value and a maximum rating. The reverse voltage (Vr) is the maximum voltage the LED can withstand in the non-conducting direction without damage. The absolute maximum ratings for forward current and power dissipation define the operational limits to prevent thermal runaway and catastrophic failure. Dynamic resistance may also be specified.

2.3 Thermal Characteristics

LED performance and lifetime are heavily influenced by temperature. The junction temperature (Tj) is the temperature at the semiconductor chip itself. The thermal resistance from junction to ambient (RθJA) or junction to solder point (RθJS) quantifies how effectively heat is transferred away from the chip. This parameter is crucial for heatsink design. The maximum allowable junction temperature (Tj max) must not be exceeded to ensure rated lifetime and maintain color stability.

3. Binning System Explanation

Manufacturing variations necessitate a binning system to ensure consistency for end-users. LEDs are sorted into bins based on key parameters.

3.1 Wavelength/Color Temperature Binning

LEDs are binned into tight groups based on their dominant wavelength (for monochromatic LEDs) or correlated color temperature and chromaticity coordinates (for white LEDs). This ensures color uniformity within a single product or across a production batch.

3.2 Luminous Flux Binning

LEDs are categorized by their luminous flux output at a specific test current. This allows designers to select components that meet precise brightness requirements and maintain consistent light levels.

3.3 Forward Voltage Binning

Components are sorted according to their forward voltage (Vf) at a specified current. This is important for power supply design, especially in series-connected strings, to ensure uniform current distribution and predictable power consumption.

4. Performance Curve Analysis

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

4.1 Current vs. Voltage (I-V) Curve

The I-V curve illustrates the non-linear relationship between forward current and forward voltage. It shows the turn-on voltage and how Vf increases with current. This curve is essential for designing the driving circuit, whether constant current or constant voltage.

4.2 Temperature Characteristics

Graphs typically show how forward voltage decreases with increasing junction temperature (for a constant current) and how luminous flux degrades as temperature rises. Understanding these relationships is critical for thermal management to maintain performance and longevity.

3.3 Spectral Power Distribution

For white LEDs, the SPD graph shows the relative intensity across the visible spectrum. It reveals the peaks from the blue pump LED and the broad phosphor emission, helping to calculate metrics like Color Rendering Index (CRI) and understand the light quality.

5. Mechanical and Package Information

The physical dimensions and construction determine how the component is mounted and interconnected.

5.1 Outline Dimension Drawing

A detailed mechanical drawing provides all critical dimensions: length, width, height, lead spacing, and overall package tolerances. This is necessary for PCB footprint design and ensuring proper fit within the assembly.

5.2 Pad Layout Design

The recommended PCB land pattern (pad geometry and size) is specified to ensure reliable solder joint formation during reflow soldering. This includes solder mask opening dimensions and any thermal relief patterns.

5.3 Polarity Identification

The method for identifying the anode and cathode is clearly indicated, usually via a marking on the package (such as a notch, dot, or cut corner) or asymmetric lead shapes. Correct polarity is essential for proper operation.

6. Soldering and Assembly Guidelines

Proper handling and soldering are critical to reliability.

6.1 Reflow Soldering Profile

A recommended reflow temperature profile is provided, including preheat, soak, reflow peak temperature, and cooling rates. The maximum allowable body temperature and time above liquidus are specified to prevent damage to the LED package and internal die.

6.2 Handling Precautions

Guidelines cover protection from electrostatic discharge (ESD), which can degrade or destroy the LED chip. Recommendations may include the use of grounded workstations and wrist straps. Avoidance of mechanical stress on the lens or leads is also emphasized.

6.3 Storage Conditions

Ideal storage conditions are specified to prevent moisture absorption (which can cause "popcorning" during reflow) and material degradation. This typically involves storing components in a dry environment at controlled temperature and humidity, often in moisture barrier bags with desiccant.

7. Packaging and Ordering Information

Information on how components are supplied and ordered.

7.1 Packaging Specifications

Details include the reel type (e.g., tape width, pocket size), number of components per reel, and reel dimensions. For other formats, details on trays or bulk packaging are provided.

7.2 Labeling Information

The information printed on the reel or package label is explained, including part number, quantity, lot/batch code, date code, and binning information.

7.3 Part Numbering System

The model naming convention is decoded. It typically includes codes for package type, color, flux bin, voltage bin, and other key attributes, allowing precise component selection.

8. Application Recommendations

Guidance for implementing the component effectively.

8.1 Typical Application Circuits

Schematics for basic driving circuits are shown, such as a simple series resistor for low-current applications or constant current driver circuits for higher-power or precision applications. Considerations for series/parallel connections are discussed.

8.2 Design Considerations

Key design points include thermal management (heatsinking, PCB copper area), optical design (lens selection, secondary optics), and electrical design (driver selection, dimming method, protection against transients and reverse polarity).

9. Technical Comparison

While this datasheet is for a specific component, its "Revision 3" and "Forever" expired period status indicate a mature product. Compared to earlier revisions, it likely incorporates improvements in performance consistency, reliability data, or clarified specifications. Compared to potential newer alternatives, this component may offer proven reliability and cost-effectiveness for applications not requiring the latest efficiency benchmarks.

10. Frequently Asked Questions (FAQ)

Common questions based on technical parameters include: "How do I interpret the binning codes on the label?" "What is the derating curve for operating at elevated ambient temperatures?" "Can I drive this LED with a pulsed current, and what is the maximum duty cycle and frequency?" "What is the expected lumen maintenance (L70/L50) under specified operating conditions?" "How does the forward voltage shift over the lifetime of the LED?"

11. Practical Use Cases

Based on the technical profile, this LED is suitable for numerous applications. In general lighting, it can be used in LED bulbs, tubes, and panel lights. In consumer electronics, it serves as status indicators, backlighting for displays, or keyboard illumination. In automotive interiors, it can be used for dashboard lighting, dome lights, and accent lighting. Industrial applications include machine status indicators and panel lighting.

12. Operating Principle Introduction

An LED is a semiconductor diode. When a forward voltage is applied across the p-n junction, electrons and holes recombine, 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. White LEDs are typically created by coating a blue or ultraviolet LED chip with a phosphor material that absorbs some of the primary light and re-emits it at longer wavelengths, resulting in a broad spectrum perceived as white light.

13. Technology Trends

The LED industry continuously evolves. Trends include increasing luminous efficacy (more lumens per watt), improving color rendering index (CRI) and color consistency, reducing cost per lumen, and developing new form factors (miniaturization, flexible substrates). There is also a strong focus on enhanced reliability and longer lifetime under higher operating temperatures and currents. Smart lighting, involving integrated control and sensing, is another significant trend. The datasheet's "Revision 3" status reflects an earlier point in this ongoing technological progression.