LED Component Technical Datasheet - Revision 1 - Lifecycle Phase: Revision - Expired Period: Forever - Release Date: 2013-01-22 - English Technical Documentation

1. Product Overview

This technical datasheet pertains to an LED component currently in the "Revision" phase of its lifecycle. The document's primary function is to establish a formal record of this specific revision, ensuring traceability and proper version control within engineering and manufacturing processes. The core information provided is the lifecycle status, revision number, and the official release timestamp, which are critical for inventory management, quality assurance, and ensuring the correct component version is used in production assemblies.

The "Revision" phase indicates that this component has undergone modifications or updates from a previous version. The "Expired Period: Forever" designation signifies that this revision does not have a predefined obsolescence date and remains valid for use indefinitely unless superseded by a newer revision. The release date of January 22, 2013, serves as a key reference point for the introduction of this specific component iteration into the supply chain.

2. Lifecycle and Revision Management

2.1 Lifecycle Phase: Revision

The lifecycle phase "Revision" is a critical status in component management. It denotes that the product specifications, materials, manufacturing process, or performance characteristics have been formally changed from a prior version. This could be due to design improvements, corrective actions, supplier changes, or compliance updates. Engineers and procurement specialists must reference this document to confirm they are working with Revision 1, as using an incorrect revision can lead to compatibility issues, performance deviations, or non-compliance in the final product.

2.2 Revision Number: 1

The revision number "1" is the identifier for this specific set of component specifications. It is the primary key for tracking changes. In a typical numbering scheme, this suggests it is the first formal revision following an initial release (which might be Revision 0 or A). All technical parameters, mechanical drawings, and performance data associated with this LED are defined under Revision 1. Any future changes would result in a new revision number (e.g., Revision 2), and a new corresponding document would be issued.

2.3 Expired Period and Release Date

The "Expired Period: Forever" is an important administrative parameter. It means there is no planned end-of-life (EOL) or last-time-buy (LTB) date associated with this revision at the time of release. The component is intended to remain in active production and procurement status. The "Release Date: 2013-01-22 11:08:45.0" provides an exact timestamp for when this revision was officially approved and released for use. This precise dating is essential for auditing, for understanding the historical context of a product's bill of materials (BOM), and for investigating field issues tied to specific manufacturing periods.

3. Technical Parameters and Specifications

While the provided PDF snippet focuses on administrative data, a complete technical datasheet for an LED component would contain extensive technical parameters. Based on standard industry documentation, the following sections detail the typical specifications that would accompany such a lifecycle document. These parameters are crucial for circuit design, thermal management, and optical performance.

3.1 Photometric and Color Characteristics

LED performance is primarily defined by its photometric output. Key parameters include luminous flux (measured in lumens), which indicates the total perceived power of light emitted. The correlated color temperature (CCT) defines the white light shade, ranging from warm white (e.g., 2700K-3000K) to cool white (e.g., 5000K-6500K). For colored LEDs, the dominant wavelength is specified (e.g., 525nm for green). Color Rendering Index (CRI) is critical for white LEDs, indicating how accurately colors are rendered under the LED's light compared to a natural light source; a CRI above 80 is typical for general lighting, while values above 90 are used for high-quality applications.

3.2 Electrical Parameters

The electrical characteristics define how the LED operates within a circuit. The forward voltage (Vf) is the voltage drop across the LED when it is emitting light at a specified test current. This is a critical parameter for driver design. The forward current (If) is the recommended operating current, typically in the range of 20mA to 150mA for mid-power LEDs. Maximum ratings for reverse voltage and peak forward current are also specified to prevent device damage. Understanding these parameters is essential for selecting appropriate current-limiting resistors or constant-current drivers to ensure stable and long-lasting operation.

3.3 Thermal Characteristics

LED performance and lifespan are heavily influenced by temperature. The junction temperature (Tj) is the temperature at the semiconductor chip itself. Key thermal parameters include the thermal resistance from the junction to the solder point or ambient air (Rth j-sp or Rth j-a). A lower thermal resistance indicates better heat dissipation. The datasheet will also specify maximum allowable junction temperature (Tj max). Exceeding this limit accelerates lumen depreciation and can cause catastrophic failure. Proper heatsinking and PCB thermal design are mandatory to keep the junction temperature within safe operating limits.

4. Binning and Classification System

Due to manufacturing variances, LEDs are sorted into performance bins. The binning system ensures consistency for the end user.

4.1 Flux and Color Binning

LEDs are binned primarily by luminous flux and chromaticity coordinates (which define color). A flux bin code (e.g., L1, L2, L3) indicates the minimum and maximum luminous output at a standard test current. Color bins are defined on a chromaticity diagram (like the CIE 1931 chart), grouping LEDs with very similar color points to avoid visible color differences in an array. Tight binning is essential for applications requiring uniform appearance, such as display backlighting or architectural lighting.

4.2 Forward Voltage Binning

Forward voltage (Vf) is also binned. While less critical for color consistency, Vf binning helps in designing efficient driver circuits and can be important for applications powered in series strings, where a large Vf variation can lead to current imbalance. Typical Vf bins might have ranges of 0.1V or 0.2V.

5. Performance Curves and Graphs

Datasheets include graphical data to illustrate performance under various conditions.

5.1 Current vs. Voltage (I-V) Curve

The I-V curve shows the relationship between forward current and forward voltage. It is non-linear, with a characteristic "knee" voltage where conduction begins. This graph is used to determine the operating point and to understand how Vf changes with current and temperature.

5.2 Relative Luminous Flux vs. Forward Current

This graph shows how light output increases with drive current. It is typically linear at lower currents but may saturate or become sub-linear at higher currents due to efficiency droop and thermal effects. It helps designers balance brightness against efficiency and device stress.

5.3 Relative Luminous Flux vs. Junction Temperature

This is one of the most important graphs, showing how light output decreases as the LED's junction temperature rises. The curve demonstrates thermal quenching. Effective thermal management is crucial to maintain light output over the product's lifetime.

5.4 Spectral Power Distribution

The SPD graph plots the intensity of light emitted at each wavelength. For white LEDs (typically blue chip + phosphor), it shows the blue peak from the chip and the broader yellow/red emission from the phosphor. This graph is used to calculate CCT and CRI and to understand the color quality of the light.

6. Mechanical and Package Information

The physical package ensures reliable electrical connection and thermal path.

6.1 Package Dimensions and Outline Drawing

A detailed mechanical drawing provides all critical dimensions: length, width, height, lead spacing, and tolerances. This is essential for PCB footprint design and ensuring the component fits within the assembly's spatial constraints.

6.2 Pad Layout and Solder Pad Design

The recommended PCB land pattern (solder pad geometry) is provided to ensure a reliable solder joint, proper thermal transfer to the PCB, and to prevent tombstoning during reflow. The datasheet specifies pad size, shape, and spacing.

6.3 Polarity Identification

Clear markings indicate the anode and cathode. This is typically shown via a notch, a cut corner, a dot, or a marking on the package. Correct polarity is mandatory for the device to function.

7. Soldering and Assembly Guidelines

7.1 Reflow Soldering Profile

A detailed reflow profile is provided, including preheat, soak, reflow, and cooling stages. Key parameters are peak temperature (typically 260°C maximum for a specified time, e.g., 10 seconds) and time above liquidus. Adhering to this profile prevents thermal damage to the LED package and internal die.

7.2 Handling and Storage Precautions

LEDs are sensitive to electrostatic discharge (ESD). Handling should be performed in an ESD-protected environment using grounded equipment. Storage conditions are specified, usually in a dry, temperature-controlled environment to prevent moisture absorption, which can cause "popcorning" during reflow.

8. Application Notes and Design Considerations

8.1 Typical Application Circuits

Basic circuit configurations are shown, such as series connection with a current-limiting resistor for low-voltage DC supply, or parallel connection considerations. Guidance for using constant-current drivers is emphasized for optimal performance and longevity.

8.2 Thermal Management Design

This is a critical section. Recommendations are given for PCB layout to enhance heat dissipation: using thermal vias under the thermal pad, employing a copper pour on the PCB, and potentially attaching the assembly to a metal core PCB (MCPCB) or heatsink. The goal is to minimize the thermal path resistance from the LED junction to the ambient environment.

8.3 Optical Design Considerations

For applications requiring specific beam patterns, secondary optics like lenses or reflectors may be needed. The datasheet may provide information on the LED's viewing angle and spatial radiation pattern to aid in optical system design.

9. Reliability and Lifetime

LED lifetime is typically defined as the operating time until the luminous flux depreciates to a certain percentage (often 70% or 50%) of its initial value, denoted as L70 or L50. Lifetime is highly dependent on operating conditions, especially junction temperature and drive current. The datasheet may present lifetime curves (e.g., lumen maintenance graphs) based on standardized testing (like IESNA LM-80), showing projected lifetime under different temperature and current scenarios.

10. Ordering Information and Model Number Decoding

A complete model number string encodes the key attributes of the LED. It typically includes information such as the package type (e.g., 2835 for 2.8mm x 3.5mm), color temperature or wavelength, flux bin, color bin, and forward voltage bin. The specific revision number (e.g., "-R1" for Revision 1) is a crucial part of this string, ensuring the correct component version is ordered and received.

11. Technical Comparison and Industry Context

While this specific document (Revision 1, 2013) represents a snapshot in time, LED technology has advanced significantly. Modern LEDs often offer higher efficacy (lumens per watt), improved color consistency with tighter binning, higher maximum allowable junction temperatures, and better reliability. The principles outlined in this datasheet—regarding electrical driving, thermal management, and careful attention to specifications—remain foundational. The "Revision" lifecycle phase documented here is a universal process in electronics, ensuring continuous improvement and traceability from legacy components to the latest generations.

12. Frequently Asked Questions (FAQ)

Q: What does "LifecyclePhase: Revision" mean for my design?
A: It means you are using a specific, documented version of the component. You must ensure your Bill of Materials (BOM) specifies "Revision 1" to guarantee you receive the exact part with the performance characteristics outlined in this datasheet. Using a different revision could alter performance.

Q: Why is the "Expired Period" listed as "Forever"?
A> This indicates the manufacturer has no current plans to obsolete this specific revision. However, "Forever" is an administrative term and does not guarantee perpetual availability; market forces or technological shifts can eventually lead to an End-of-Life notice, even for revisions with this designation.

Q: How do I use the release date information?
A: The release date is vital for traceability. If a field failure is investigated, knowing the revision and its release date allows you to identify which production batches used this component and narrow down potential root causes related to a specific component version.

Q: The PDF shows minimal data. Where are the full technical specs?
A: The provided snippet is likely a header or cover page from a larger document. The complete technical datasheet would contain all the sections detailed above (electrical, optical, thermal specs, graphs, mechanical drawings). Always refer to the full document for design purposes.