LED Component Lifecycle Document - Revision 3 - Release Date 2014-12-05 - English Technical Specification

1. Document Overview

This technical document serves as the definitive specification for the lifecycle management of a specific electronic component, identified here as an LED for contextual purposes. The core information pertains to its revision history and release status. The document is structured to provide engineers, procurement specialists, and quality assurance personnel with clear, unambiguous data regarding the component's approved version and its validity period. Understanding this lifecycle information is critical for ensuring design consistency, manufacturing repeatability, and long-term supply chain stability in electronic product development.

2. Core Lifecycle Parameters

The document repeatedly emphasizes a single, consistent set of lifecycle parameters, indicating this is the primary data point for the component's status.

2.1 Lifecycle Phase

The LifecyclePhase is explicitly stated as Revision. This denotes that the component specifications have undergone changes from a previous version. A revision phase typically implies functional or parametric modifications that are backward-compatible or have minor adjustments, as opposed to a completely new product introduction or an end-of-life status.

2.2 Revision Number

The associated Revision Number for this phase is 3. This integer indicates the sequence of formal revisions. Revision 3 supersedes all previous revisions (e.g., Revision 1, Revision 2). It is essential for users to reference this specific revision number in all design files, bills of materials (BOMs), and quality documentation to avoid discrepancies.

2.3 Expired Period

The Expired Period is defined as Forever. This is a significant declaration meaning there is no planned expiration or obsolescence date for this specific revision under normal circumstances. The component is intended for ongoing, long-term production availability. This status provides supply chain security for products designed with this component.

2.4 Release Date

The Release Date is precisely timestamped as 2014-12-05 11:59:33.0. This marks the official date and time when Revision 3 was authorized and released for production and design use. All specifications contained within the full datasheet (implied by this header) are valid as of this moment.

3. Technical Parameter Analysis

While the provided snippet focuses on lifecycle metadata, a complete technical datasheet for an LED component would contain extensive parameters. The following sections detail the typical categories of data that accompany such lifecycle information, based on standard industry practice for LED documentation.

3.1 Photometric Characteristics

Photometric parameters define the light output and quality. Key specifications include Luminous Flux (measured in lumens, lm), which indicates total visible light output. Luminous Intensity (measured in candelas, cd) describes the light power per unit solid angle. Correlated Color Temperature (CCT, measured in Kelvin, K) specifies whether the light appears warm, neutral, or cool white. Color Rendering Index (CRI, Ra) is a measure of how accurately the light source reveals the colors of objects compared to a natural light source, with higher values (closer to 100) being better. Dominant Wavelength or peak wavelength defines the perceived color for monochromatic LEDs.

3.2 Electrical Parameters

Electrical characteristics are fundamental for circuit design. The Forward Voltage (Vf) is the voltage drop across the LED when operating at a specified current, typically provided as a range (e.g., 2.8V to 3.4V). The Forward Current (If) is the recommended operating current, often a nominal value like 20mA, 60mA, or 150mA depending on the package and power rating. Reverse Voltage (Vr) indicates the maximum voltage the LED can withstand when biased in the non-conducting direction. Power Dissipation (Pd) is the maximum allowable power the package can handle, factoring in both electrical and thermal limits.

3.3 Thermal Characteristics

Thermal management is crucial for LED performance and longevity. The Junction-to-Ambient Thermal Resistance (RθJA) quantifies how effectively heat travels from the semiconductor junction to the surrounding air. A lower value indicates better heat dissipation. The Maximum Junction Temperature (Tj max) is the highest allowable temperature at the LED chip itself; exceeding this limit drastically reduces lifespan and can cause immediate failure. These parameters dictate the necessary heatsinking or PCB design for reliable operation.

4. Binning and Sorting System

LED manufacturing yields natural variations. A binning system categorizes components into groups with tightly controlled parameters.

4.1 Wavelength / Color Temperature Binning

White LEDs are sorted into bins based on their CCT (e.g., 2700K, 3000K, 4000K, 5000K, 6500K) and often within a MacAdam ellipse step (e.g., 2-step, 3-step) to ensure color consistency. Color LEDs are binned by dominant wavelength (e.g., 625nm ± 2nm).

4.2 Luminous Flux Binning

LEDs are sorted by their light output at a standard test current. Bins are defined by a minimum and/or maximum luminous flux value (e.g., Bin A: 20-22 lm, Bin B: 22-24 lm). This allows designers to select the appropriate brightness grade for their application.

4.3 Forward Voltage Binning

To simplify driver design and ensure consistent current distribution in arrays, LEDs may be binned by their forward voltage drop at a specified test current (e.g., Vf Bin 1: 3.0V-3.2V, Vf Bin 2: 3.2V-3.4V).

5. Performance Curve Analysis

Graphical data provides deeper insight into component behavior under varying 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 essential for determining the operating point and designing the current-limiting circuit (e.g., resistor or constant current driver). The curve typically shows a sharp turn-on at the threshold voltage.

5.2 Temperature Characteristics

Graphs illustrate how key parameters change with temperature. Luminous flux typically decreases as junction temperature increases. Forward voltage also decreases with rising temperature, which can affect current regulation if not properly managed. These curves are vital for designing systems that maintain performance across the intended operating temperature range.

5.3 Spectral Power Distribution (SPD)

The SPD graph plots the relative intensity of light emitted at each wavelength. For white LEDs, it shows the blue pump peak and the broader phosphor-converted spectrum. This graph is key for analyzing color quality metrics like CRI and for applications with specific spectral sensitivity.

6. Mechanical and Packaging Information

Physical specifications ensure proper fit and assembly.

6.1 Dimensional Outline Drawing

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

6.2 Pad Layout Design

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

6.3 Polarity Identification

The method for identifying the anode and cathode is clearly indicated, typically via a marking on the component (e.g., a notch, a dot, a green line, or a cut corner) or by asymmetric lead lengths. Correct polarity is essential for function.

7. Soldering and Assembly Guidelines

7.1 Reflow Soldering Profile

A recommended reflow temperature profile is provided, including preheat, soak, reflow peak temperature (typically not exceeding 260°C for a specified time, e.g., 10 seconds above 240°C), and cooling rates. Adhering to this profile prevents thermal damage to the LED package and internal die.

7.2 Handling Precautions

Precautions include using ESD (electrostatic discharge) protection during handling, avoiding mechanical stress on the lens, and preventing contamination of the optical surface. Some LEDs are sensitive to moisture and may require baking before soldering if the packaging has been exposed.

7.3 Storage Conditions

Ideal storage conditions are specified, usually in a cool, dry environment with controlled humidity (e.g., <40% relative humidity at 25°C) to prevent moisture absorption and degradation of materials.

8. Application Recommendations

8.1 Typical Application Circuits

Basic application circuits are shown, such as a simple series resistor circuit for low-current indicators or a constant current driver circuit for power LEDs. Design equations for calculating the current-limiting resistor are often included.

8.2 Design Considerations

Key considerations include thermal management (PCB copper area, heatsinks), optical design (lenses, reflectors), electrical layout to minimize noise, and derating guidelines for operating at elevated temperatures to ensure long-term reliability.

9. Reliability and Lifetime

While not in the snippet, a full datasheet defines lifetime expectations, often expressed as L70 or L50 (time until luminous flux degrades to 70% or 50% of initial output) under specified operating conditions (e.g., 25°C ambient, nominal current). This is based on accelerated life testing and is a critical parameter for lighting applications.

10. Interpretation of the Provided Data

The repeated lines in the provided PDF content strongly suggest a document header or footer that appears on every page. The single datum--LifecyclePhase: Revision : 3, Expired Period: Forever, Release Date: 2014-12-05--is the consistent, defining metadata for the entire accompanying technical specification. Engineers must verify that any printed or downloaded copy of the full datasheet carries this exact revision and release information to ensure they are working with the correct and current specifications. The "Forever" expired period for Revision 3, released in late 2014, indicates a mature, stable product version that has been qualified for long-term use, offering significant supply chain predictability for designs implemented after that date.