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

1. Product Overview

This technical document provides comprehensive information regarding the lifecycle status and revision history of a specific LED component. The primary focus is on the formal declaration of the component's current revision state, its release timeline, and the associated validity period. Understanding this information is crucial for engineers, procurement specialists, and quality assurance teams to ensure the use of the correct and authorized component version in their designs and production processes. The document serves as a formal record of the component's technical data sheet status.

The core advantage of maintaining such detailed lifecycle documentation is traceability and version control. It allows all stakeholders in the supply chain to reference the exact specification that was valid at the time of design or purchase. The target market for this information includes original equipment manufacturers (OEMs), electronic design houses, and aftermarket service providers who require guaranteed consistency in component performance and specifications over the product's lifespan.

2. Lifecycle and Revision Information

The document repeatedly and consistently specifies a single, critical set of data points regarding the component's formal status.

2.1 Lifecycle Phase

The LifecyclePhase is explicitly stated as Revision. This indicates that the component and its associated documentation are in an active state of development or improvement. A 'Revision' phase typically follows an initial release and incorporates changes, which could range from minor typographical corrections in the datasheet to more substantial updates in recommended operating conditions, test procedures, or performance characteristics. It signifies that this is not a preliminary draft nor an obsolete document, but an actively maintained version.

2.2 Revision Number

The revision number is specified as 2. This numerical identifier is essential for tracking the evolution of the component's specifications. Revision 2 implies there was at least one prior released version (Revision 1). The changes incorporated in Revision 2 should be detailed in a revision history section, which, while not present in the provided excerpt, is a standard part of full technical documentation. Engineers must always verify they are using the latest revision to benefit from the most accurate and up-to-date information.

2.3 Release Date and Expiration

The Release Date is precisely recorded as 2014-12-05 12:02:39.0. This timestamp provides an exact point of reference for when this specific revision (Revision 2) was officially published and made available for use.

The Expired Period is declared as Forever. This is a significant designation. It means that the technical data contained in this revision does not have a pre-defined end-of-life date for its validity from the publisher's perspective. The specifications are considered perpetually applicable unless superseded by a newer revision. However, 'Forever' in this context pertains to the document's validity, not necessarily the production availability of the physical component, which is governed by separate product lifecycle management.

3. Technical Parameters and Specifications

While the provided PDF excerpt focuses on metadata, a complete technical datasheet for an LED component would contain several critical sections. The following is a detailed explanation of the parameters typically found in such a document, which are implied to be defined within this revision.

3.1 Photometric and Color Characteristics

This section quantitatively defines the light output and quality of the LED. Key parameters include:

• Luminous Flux: The total visible light emitted by the LED, measured in lumens (lm). This is often presented with minimum, typical, and maximum values at a specified test current.
• Dominant Wavelength / Correlated Color Temperature (CCT): For colored LEDs, the dominant wavelength (in nanometers) defines the perceived color. For white LEDs, the CCT (in Kelvin, e.g., 3000K warm white, 6500K cool white) describes the color appearance.
• Color Rendering Index (CRI): For white LEDs, CRI (Ra) indicates how accurately the light source reveals the true colors of objects compared to a natural reference light. A higher CRI (closer to 100) is better for applications requiring accurate color perception.
• Viewing Angle: The angular span over which the luminous intensity is at least half of the maximum intensity, measured in degrees.

3.2 Electrical Parameters

These parameters define the electrical operating conditions of the LED.

• Forward Voltage (Vf): The voltage drop across the LED when a specified forward current is applied. It is typically given as a range (e.g., 2.8V to 3.4V) at a test current like 20mA or 150mA, depending on power.
• Forward Current (If): The recommended continuous DC current for normal operation. Exceeding the absolute maximum rating can cause permanent damage.
• Reverse Voltage (Vr): The maximum voltage the LED can withstand when connected in reverse bias without breaking down. This is usually a relatively low value (e.g., 5V).

3.3 Thermal Characteristics

LED performance and lifespan are highly dependent on junction temperature.

• Thermal Resistance (Rth j-s): The resistance to heat flow from the LED junction to the solder point or case. A lower value indicates better heat dissipation capability.
• Maximum Junction Temperature (Tj max): The highest allowable temperature at the semiconductor junction. Operating above this limit drastically reduces lifetime and can cause immediate failure.

4. Binning and Classification System

Due to manufacturing variances, LEDs are sorted into performance bins. This ensures consistency within a batch.

• Flux Binning: LEDs are grouped based on their measured luminous flux output at a standard test condition.
• Color Binning: For white LEDs, this involves sorting based on CCT and sometimes within a CCT bin based on chromaticity coordinates (e.g., MacAdam ellipses). For colored LEDs, it's based on dominant wavelength.
• Forward Voltage Binning: Sorting based on the Vf range to ensure uniform electrical behavior in parallel circuits.

5. Performance Curve Analysis

Graphical data is essential for understanding component behavior under varying conditions.

• I-V (Current-Voltage) Curve: Shows the relationship between forward current and forward voltage. It is non-linear, characteristic of a diode.
• Relative Luminous Flux vs. Forward Current: Demonstrates how light output increases with current, typically in a linear region before efficiency drops at high currents.
• Relative Luminous Flux vs. Junction Temperature: Shows the depreciation of light output as the LED's junction temperature rises. This is critical for thermal management design.
• Spectral Power Distribution (SPD): A graph plotting the intensity of light emitted at each wavelength, defining the color characteristics.

6. Mechanical and Package Information

This section provides the physical dimensions and assembly details.

• Package Outline Drawing: A detailed diagram with all critical dimensions (length, width, height, lead spacing) and tolerances.
• Pad Layout (Footprint): The recommended copper pad pattern on the printed circuit board (PCB) for soldering, including solder mask and solder paste recommendations.
• Polarity Identification: Clear marking of the anode and cathode, usually via a notch, cut corner, or marker on the package.

7. Soldering and Assembly Guidelines

Proper assembly is vital for reliability.

• Reflow Soldering Profile: A time-temperature graph specifying the recommended preheat, soak, reflow, and cooling phases. It includes peak temperature limits to avoid damaging the LED package or internal die.
• Hand Soldering Instructions: If applicable, guidelines for iron temperature, tip size, and maximum soldering time per lead.
• Cleaning and Handling: Precautions regarding electrostatic discharge (ESD) sensitivity and the use of cleaning solvents compatible with the LED lens material.
• Storage Conditions: Recommended temperature and humidity ranges for storing components before use.

8. Application Notes and Design Considerations

This section translates specifications into practical design advice.

• Typical Application Circuits: Schematics showing the LED driven by a constant current source, often with series current-limiting resistors for simple DC drive.
• Thermal Management: Detailed guidance on PCB design for heat sinking, such as using thermal vias, adequate copper area, and possibly a metal-core PCB for high-power applications.
• Optical Considerations: Advice on secondary optics (lenses, diffusers) and the impact of the viewing angle on the final illumination pattern.
• Dimming and Pulsing: Information on compatibility with pulse-width modulation (PWM) dimming and any limitations regarding maximum pulse current or frequency.

9. Frequently Asked Questions (FAQ)

Addressing common queries based on technical parameters.

• Q: Can I operate the LED at a higher current for more brightness? A: Operating above the specified absolute maximum forward current will increase light output temporarily but will drastically reduce lifespan, cause color shift, and may lead to catastrophic failure. Always adhere to recommended operating conditions.
• Q: Why is thermal management so important for LEDs? A: High junction temperature is the primary cause of LED degradation. It leads to lumen depreciation (reduced light output), color shift over time, and ultimately, premature failure. Effective heat sinking is non-negotiable for reliable performance.
• Q: What is the significance of the 'Forever' expiration period? A: It indicates that the technical specifications in this document revision are not time-limited. They remain the definitive reference for this version of the component. However, for production and sourcing, you must consult separate notifications regarding product longevity, obsolescence, and last-time-buy dates.

10. Revision Control and Document Integrity

The repeated lines in the provided PDF excerpt emphasize a key principle in technical documentation: unambiguous declaration of the document's identity and status. Each instance of "LifecyclePhase: Revision : 2" and "Release Date: 2014-12-05" serves as a watermark, ensuring that any printed or copied page can be traced back to the correct revision. This prevents the use of outdated or incorrect specifications, which is a critical aspect of quality management in electronic manufacturing. Engineers must always verify these header/footer details on every page of a datasheet before finalizing a design.