LED Component Lifecycle Document - Revision 3 - Release Date 2013-11-15 - English Technical Specification

1. Product Overview

This technical document provides the formal lifecycle and revision control information for a specific electronic component, identified here as an LED for contextual purposes. The core information conveyed is the establishment of a definitive revision state, designated as Revision 3. This revision carries a permanent status, indicated by an "Expired Period" of "Forever," signifying that this version of the specification is intended to remain valid and referenceable indefinitely without planned obsolescence. The official point of release for this revision was precisely timestamped on November 15, 2013, at 08:38:52.0. The repetitive nature of the provided data underscores a standardized record-keeping or labeling process, likely applied across multiple units, batches, or document pages to ensure traceability and consistency.

2. Technical Parameter Deep Dive

While specific photometric, electrical, and thermal parameters are not enumerated in the provided snippet, the document's structure implies a rigorous technical foundation. A complete datasheet for an LED component would typically include the following sections, which are critical for design engineers:

2.1 Photometric Characteristics

This section would detail the light output properties. Key parameters include Luminous Flux (measured in lumens, lm), which defines the total perceived power of light emitted. Luminous Intensity (candelas, cd) describes the directional brightness. The dominant wavelength or correlated color temperature (CCT, in Kelvin) specifies the color of the emitted light, whether cool white, warm white, or a specific monochromatic color like red or blue. Color Rendering Index (CRI) is also a crucial metric, indicating how accurately the light source reveals the true colors of objects compared to a natural reference.

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 its nominal current. It varies with the semiconductor material (e.g., ~3.2V for typical InGaN blue/white LEDs, ~2.0V for AlGaInP red LEDs). The Forward Current (If) is the recommended operating current, often 20mA, 150mA, or higher for power LEDs. Reverse Voltage (Vr) specifies the maximum allowable voltage in the reverse direction before potential damage. Dynamic resistance may also be specified for modeling purposes.

2.3 Thermal Characteristics

LED performance and longevity are heavily dependent on thermal management. The Junction-to-Ambient Thermal Resistance (RθJA) is a critical parameter, expressed in °C/W. It quantifies how effectively heat can dissipate from the semiconductor junction to the surrounding environment. A lower RθJA value indicates better thermal performance. The maximum Junction Temperature (Tj max) defines the absolute upper limit for the semiconductor's operating temperature, beyond which rapid degradation or failure occurs. Proper heatsinking is essential to keep the operating Tj well below this maximum.

3. Binning System Explanation

Manufacturing variations necessitate a binning system to categorize components based on key performance parameters. This ensures consistency for end-users.

3.1 Wavelength / Color Temperature Binning

LEDs are sorted into bins based on their peak wavelength (for colored LEDs) or their correlated color temperature (for white LEDs). A typical white LED binning might group units into ranges like 2700K-3000K (warm white), 4000K-4500K (neutral white), and 6000K-6500K (cool white). Tight binning is essential for applications requiring uniform color appearance, such as display backlighting or architectural lighting.

3.2 Luminous Flux Binning

Components are also binned according to their light output at a specified test current. For example, bins may be defined in 5% or 10% increments of the nominal luminous flux. This allows designers to select LEDs that meet minimum brightness requirements or to match brightness levels across multiple units in an array.

3.3 Forward Voltage Binning

Sorting by forward voltage (Vf) helps in designing efficient driver circuits, especially when connecting multiple LEDs in series. Matching Vf bins can lead to more uniform current distribution and simplified power supply design.

4. Performance Curve Analysis

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

4.1 Current-Voltage (I-V) Characteristic Curve

The I-V curve is non-linear, showing a sharp increase in current once the forward voltage exceeds a threshold. This graph is essential for determining the operating point and for selecting appropriate current-limiting circuitry, such as constant current drivers.

4.2 Temperature Dependency

Several key plots illustrate temperature effects: Luminous Flux vs. Junction Temperature typically shows output decreasing as temperature rises. Forward Voltage vs. Junction Temperature usually shows a negative coefficient, meaning Vf decreases slightly with increasing temperature. These relationships are vital for predicting performance in real-world, non-ideal thermal environments.

4.3 Spectral Power Distribution

This plot shows the relative intensity of light emitted at each wavelength. For white LEDs (typically blue LED + phosphor), it shows the blue peak from the chip and the broader yellow/red emission from the phosphor. The shape of this curve determines the color quality metrics like CRI and CCT.

5. Mechanical and Packaging Information

Physical specifications ensure proper integration into the final product.

5.1 Dimensional Outline Drawing

A detailed mechanical drawing provides all critical dimensions: length, width, height, lens shape, and lead/pad spacing. Tolerances are specified for each dimension. Common package sizes include 2835 (2.8mm x 3.5mm), 5050 (5.0mm x 5.0mm), and 5730 (5.7mm x 3.0mm).

5.2 Pad Layout and Solder Mask Design

The recommended footprint for PCB layout is provided, including pad size, shape, and solder mask opening. Adhering to these recommendations is crucial for achieving reliable solder joints and proper thermal conduction away from the LED.

5.3 Polarity Identification

Clear markings indicate the anode (+) and cathode (-) terminals. This may be a notch, a dot, a cut corner, or differently shaped leads. Incorrect polarity will prevent the LED from illuminating and may damage it.

6. Soldering and Assembly Guidelines

Proper handling ensures reliability and prevents damage during manufacturing.

6.1 Reflow Soldering Profile

A detailed temperature vs. time profile is specified, including preheat, soak, reflow peak temperature, and cooling rates. The maximum peak temperature (typically 260°C for a few seconds) must not be exceeded to avoid damaging the LED's internal structure, lens, or phosphor.

6.2 Precautions and Handling

Guidelines include warnings against applying mechanical stress to the lens, using ESD (Electrostatic Discharge) precautions during handling, and avoiding contamination of the optical surface. Recommendations for cleaning agents compatible with the LED materials may also be provided.

6.3 Storage Conditions

To maintain solderability and prevent moisture absorption (which can cause "popcorning" during reflow), LEDs should be stored in a controlled environment, typically below 30°C and 60% relative humidity. If the moisture sensitivity level (MSL) is specified, baking may be required before use if exposure limits are exceeded.

7. Packaging and Ordering Information

This section covers logistics and identification.

7.1 Packaging Specifications

Details include the quantity per reel (e.g., 2000 pieces), reel dimensions, and tape-and-reel specifications (carrier tape width, pocket size). This information is necessary for automated pick-and-place assembly equipment.

7.2 Labeling and Identification

The information on the reel label typically includes the part number, quantity, lot/batch number, date code, and binning codes. The lot number is key for traceability, linking back to the specific manufacturing data.

7.3 Part Numbering System

The part number is a code that encapsulates the product's key attributes. It may include fields representing the package size, color, flux bin, voltage bin, color temperature bin, and special features. Decoding this system allows precise ordering of the required component variant.

8. Application Recommendations

8.1 Typical Application Circuits

Schematics for basic drive circuits are often included. For low-current LEDs, a simple series resistor is sufficient. For higher-power LEDs, constant current drivers (switch-mode or linear) are recommended to ensure stable light output and long life. Protection elements like transient voltage suppressors (TVS) may be suggested for automotive or industrial environments.

8.2 Design Considerations

Critical design factors include thermal management (PCB copper area, thermal vias, possible external heatsink), optical design (lens selection, reflectors, diffusers), and electrical layout (minimizing loop area, proper grounding) to ensure performance, reliability, and EMI compliance.

9. Technical Comparison

While not explicitly comparing to other products, the specifications themselves define this component's position. A component with a "Forever" lifecycle phase suggests it is a mature, stable product intended for long-term availability, contrasting with parts that have planned end-of-life dates. Its 2013 release date indicates it is based on established, proven technology rather than the latest cutting-edge efficiency, which may appeal to designs requiring long-term supply chain stability.

10. Frequently Asked Questions (FAQ)

Q: What does "LifecyclePhase: Revision" mean?
A: It indicates the document/component is in a state of being revised or updated. "Revision: 3" specifies this is the third official version of the document.

Q: What is the implication of "Expired Period: Forever"?
A: This denotes that this revision of the document has no planned expiration or end-of-life date. It is intended to remain the valid reference indefinitely, which is crucial for products with long lifecycles.

Q: Why is the Release Date important?
A: It provides a definitive timestamp for when this specific revision became official. This is essential for version control, traceability, and ensuring all parties in the supply chain are referencing the same specifications.

11. Practical Use Case

Consider a designer working on a commercial lighting fixture intended for a 10-year product lifecycle. Selecting a component documented with "Revision 3, Forever Expired Period" provides confidence that the technical specifications will not become obsolete during the product's manufacturing and support period. The designer can reliably base thermal, optical, and electrical designs on this datasheet, knowing the parameters are fixed. The 2013 release date further suggests the component has a long track record in the field, potentially with known reliability data.

12. Principle Introduction

An LED is a semiconductor diode. When a forward voltage is applied, electrons recombine with holes within the device, releasing energy in the form of photons. The color of the light is determined by the energy band gap of the semiconductor material used (e.g., Gallium Nitride for blue/UV, Aluminum Gallium Indium Phosphide for red/yellow/green). White LEDs are typically created by coating a blue LED chip with a phosphor material that absorbs some of the blue light and re-emits it as yellow light; the mixture of blue and yellow light is perceived as white.

13. Development Trends

The LED industry continuously evolves. Key trends include increasing luminous efficacy (more lumens per watt), improving color quality (higher CRI with full-spectrum or violet-pump phosphors), and greater reliability. Miniaturization continues with smaller packages delivering higher flux density. Smart and connected lighting, integrating sensors and controls, is a major application driver. Furthermore, there is a strong focus on human-centric lighting, tuning spectral output to support circadian rhythms. The concept of a "Forever" lifecycle document, as seen here, reflects the maturity of certain foundational package technologies that become industry standards.