LED Component Lifecycle Phase Revision Specification - Revision 3 - Release Date 2013-11-04 - English Technical Document

1. Product Overview

This technical document provides critical lifecycle management information for a specific electronic component, identified here as an LED component for illustrative purposes. The core function of this document is to formally declare the current revision status and release details, ensuring traceability and version control within engineering and manufacturing processes. The primary data point is the establishment of Revision 3 as the active and authoritative version, released on a specific date, with an indefinite validity period. This indicates a mature, stable product specification that is not subject to scheduled obsolescence, providing long-term reliability for design-in and production planning.

2. Lifecycle and Revision Management

The document's central theme is the formalization of the component's revision state. This is a fundamental aspect of component data sheets, providing a clear reference point for engineers, procurement specialists, and quality assurance teams.

2.1 Lifecycle Phase: Revision

The lifecycle phase is explicitly stated as "Revision." This denotes that the component's design and specification are not in an initial prototyping (Alpha/Beta) or obsolete (EOL) phase. It is in a state of controlled updates and improvements. A "Revision" phase implies the product is in full production, and any changes are managed through formal revision control, ensuring backward compatibility or clearly documented alterations.

2.2 Revision Number: 3

The revision number is a key identifier for tracking changes. Revision 3 signifies that this is the third formally released version of the component's specification. Each increment from a previous revision (e.g., Rev. 2 to Rev. 3) typically corresponds to a set of documented Engineering Change Orders (ECOs). These changes could include minor adjustments to electrical tolerances, updates to recommended materials, corrections in dimensional drawings, or enhancements to performance characteristics based on extended testing. It is crucial for users to always reference the latest revision to ensure their designs and processes align with the current specification.

2.3 Release Date: 2013-11-04 14:49:13.0

The release date provides a precise timestamp for when Revision 3 became official. The inclusion of the time (14:49:13.0) suggests a highly controlled document management system. This date serves as a baseline for determining which manufacturing lots or design projects are compliant with this revision. For any design or production activity initiated after this date, Revision 3 is the applicable standard.

2.4 Expired Period: Forever

The "Expired Period" is declared as "Forever." This is a significant statement regarding the document's and, by extension, the revision's validity. It indicates that this revision of the specification does not have a pre-defined end-of-life date. The technical data is considered perpetually valid unless superseded by a future revision. This provides stability and confidence for long-term projects, eliminating concerns about the specification becoming invalidated after a certain period. It does not mean the product itself will never be discontinued, but rather that this specific document revision remains the correct reference indefinitely for products manufactured to this standard.

3. Technical Parameters and Interpretation

While the provided text snippet focuses on administrative data, a full technical document for an LED component would contain extensive parameter sections. Based on the context of a lifecycle document for an LED, the following sections would be critically analyzed.

3.1 Photometric and Color Characteristics

A detailed technical document would specify key photometric parameters. The dominant wavelength or correlated color temperature (CCT) would be defined, often presented in bins or grades (e.g., 6000K-6500K for cool white). The luminous flux (in lumens) at a specific test current (e.g., 65mA) would be a central performance metric, also typically binned. Chromaticity coordinates (x, y on the CIE 1931 diagram) would be provided to define color point accuracy. The color rendering index (CRI), especially Ra and potentially R9 for red rendering, would be specified for white LEDs. Understanding these bins is essential for achieving consistent color and brightness in an application.

3.2 Electrical Parameters

The forward voltage (Vf) is a fundamental electrical parameter, measured at a specific test current. Like flux, Vf is subject to production variance and is therefore binned (e.g., 3.0V - 3.2V). The reverse voltage rating (Vr) specifies the maximum allowable voltage in the non-conducting direction. The absolute maximum ratings for forward current (If) and power dissipation (Pd) define the operational limits beyond which permanent damage may occur. The recommended operating conditions, typically a lower current than the absolute maximum, ensure optimal lifetime and performance.

3.3 Thermal Characteristics

LED performance and lifetime are profoundly influenced by temperature. The junction-to-ambient thermal resistance (RθJA) quantifies how effectively heat is dissipated from the semiconductor junction to the surrounding environment. A lower RθJA indicates better thermal performance. The document would specify the maximum allowable junction temperature (Tj max), often around 125°C. Exceeding this temperature drastically reduces luminous output and shortens the component's lifespan. Derating curves, showing the maximum allowable forward current as a function of ambient temperature, are essential for robust design.

4. Binning System Explanation

Due to manufacturing variations, LEDs are sorted into performance bins. The document would detail the binning structure for wavelength/CCT, luminous flux, and forward voltage. Each bin has a code (e.g., FL for flux, V for voltage). Designers must select appropriate bins to meet their application's requirements for color consistency and brightness uniformity. Using LEDs from a single, tight bin ensures a homogeneous appearance in the final product.

5. Performance Curve Analysis

Graphical data is vital for understanding component behavior under various conditions.

5.1 Current vs. Voltage (I-V) Curve

The I-V curve shows the nonlinear relationship between forward current and forward voltage. It is used to determine the operating point when designing the driver circuit. The curve also indicates the dynamic resistance of the LED.

5.2 Relative Luminous Flux vs. Junction Temperature

This curve demonstrates the thermal quenching effect: as the LED junction temperature increases, its light output decreases. The slope of this curve is critical for applications operating in high ambient temperatures, informing necessary thermal management and optical over-design.

5.3 Spectral Power Distribution (SPD)

The SPD graph plots the intensity of light emitted across the visible spectrum (and sometimes beyond). For white LEDs, it shows the blue pump peak and the broader phosphor-converted emission. This graph is key for analyzing color quality, identifying potential spikes, and ensuring the spectrum meets application needs (e.g., horticulture, museum lighting).

6. Mechanical and Packaging Information

Detailed dimensional drawings would be provided, showing top, side, and bottom views with critical dimensions and tolerances. The footprint or land pattern design for PCB mounting would be specified, including pad size, spacing, and recommended solder mask opening. Polarity identification (anode and cathode) would be clearly marked, typically with a visual indicator like a notch, cut corner, or marking on the package.

7. Soldering and Assembly Guidelines

Reflow soldering is the standard assembly method for surface-mount LEDs. The document would provide a detailed reflow profile, specifying the temperature ramp-up rate, preheat soak time and temperature, time above liquidus (TAL), peak temperature, and cooling rate. Adherence to this profile is mandatory to prevent thermal shock, delamination, or damage to the internal silicone and phosphor. Handling precautions to avoid electrostatic discharge (ESD) and mechanical stress would be listed. Recommended storage conditions (temperature and humidity) to preserve solderability would also be defined.

8. Packaging and Ordering Information

The tape and reel packaging specifications would be detailed, including reel diameter, tape width, pocket spacing, and orientation of components. The labeling on the reel would include the part number, revision code (e.g., Rev. 3), quantity, lot number, and date code. The part number itself would follow a specific naming convention that encodes key attributes like package size, color, flux bin, and voltage bin, allowing for precise ordering.

9. Application Recommendations

Typical application scenarios would be suggested, such as backlighting units for displays, general illumination modules, automotive interior lighting, or indicator panels. Critical design considerations would be emphasized: the necessity of a constant-current driver (not a voltage source), the paramount importance of effective thermal management via PCB copper area or heatsinks, optical design for desired beam patterns, and potential dimming methods (PWM or analog).

10. Technical Comparison and Differentiation

While not comparing to specific competitors, the document's own specifications define its advantages. A low thermal resistance (RθJA) is a key differentiator for high-power applications. A high CRI (e.g., >90) and tight color binning differentiate it in quality lighting. A high maximum junction temperature (Tj max) indicates robustness. Long-term lumen maintenance data (e.g., L70 > 50,000 hours) is a critical reliability differentiator.

11. Frequently Asked Questions (FAQ)

Q: What does "Revision 3" mean for my existing design using an older revision?
A: You must compare the Revision 3 document with your previous revision's document. Check the change history or carefully compare parameters and drawings. Some revisions may be drop-in compatible, while others may have changes requiring circuit or layout adjustments.

Q: The "Expired Period: Forever" seems unusual. Does this mean the product will never be discontinued?
A> No. "Forever" applies to the validity of this specific document revision. The product itself may eventually reach an End-of-Life (EOL) phase, which would be communicated through a separate product change notice (PCN). This statement means you can rely on this spec sheet indefinitely as the correct reference for products built to the Rev. 3 standard.

Q: How do I ensure color consistency in my product?
A> You must specify and procure LEDs from a single, narrow bin for both chromaticity (e.g., 3-step MacAdam ellipse) and luminous flux. Work with your supplier to guarantee bin-specific supply.

Q: Can I drive the LED at its absolute maximum current?
A> It is not recommended for reliable, long-life operation. Always design using the recommended operating current. The absolute maximum ratings are stress limits, not targets.

12. Practical Application Case Study

Consider designing a high-quality LED panel light for office illumination. The designer selects this LED component based on its high CRI (Ra>90) and good lumen maintenance specification. They choose a tight CCT bin (e.g., 4000K ± 100K) and a specific flux bin. The thermal design involves calculating the required heatsinking using the RθJA value and the expected power dissipation to keep the junction temperature below 105°C, ensuring long life. A constant-current driver is selected to provide 100mA per LED, within the recommended range. The PCB layout includes adequate copper pads for heat spreading, following the recommended land pattern from the mechanical drawing. The assembly house is provided with the exact reflow profile from the document to ensure proper soldering without damage.

13. Operating Principle Introduction

An LED is a semiconductor diode. When a forward voltage is applied across the p-n junction, electrons and holes recombine 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. For white LEDs, a blue-emitting semiconductor chip is coated with a phosphor layer. Part of the blue light is absorbed by the phosphor and re-emitted as longer wavelength yellow light. The mixture of the remaining blue light and the phosphor-converted yellow light appears white to the human eye.

14. Technology Trends and Developments

The LED industry continuously evolves. Trends include increasing luminous efficacy (lumens per watt), driven by improvements in chip design, phosphor technology, and package efficiency. There is a strong focus on improving color quality, with high CRI and full-spectrum LEDs becoming more common. Miniaturization continues, enabling higher density arrays. Smart and connected lighting is driving the integration of control electronics. Furthermore, there is significant R&D in areas like micro-LEDs for ultra-high-resolution displays and UV-C LEDs for sterilization applications. The lifecycle and revision management process, as documented here, is essential for tracking these incremental improvements in commercial products.