LED Component Technical Datasheet - Revision 3 - Lifecycle Phase - Release Date 2014-12-15 - English Technical Documentation

1. Product Overview

This technical datasheet provides comprehensive information for an LED component currently in the Revision 3 lifecycle phase. The document was officially released on December 15, 2014, and is designated with an indefinite expiration period, indicating its status as a stable, long-term reference specification. The core advantage of this component lies in its mature and well-documented revision status, ensuring consistency and reliability for design and manufacturing processes. It is targeted at applications requiring dependable, standardized lighting solutions where long-term availability and stable technical parameters are critical.

2. Technical Parameters Deep Objective Interpretation

While the provided excerpt focuses on document metadata, a complete datasheet for an LED component in Revision 3 would typically include detailed technical parameters. These are interpreted below based on standard industry practices for such components.

2.1 Photometric and Color Characteristics

The photometric characteristics define the light output and quality. Key parameters include luminous flux, measured in lumens (lm), which indicates the total perceived power of light emitted. The correlated color temperature (CCT), measured in Kelvin (K), specifies whether the light appears warm, neutral, or cool white. Color Rendering Index (CRI) is a measure of a light source's ability to reveal the colors of various objects faithfully in comparison to a natural light source. Dominant wavelength or peak wavelength, measured in nanometers (nm), defines the perceived color for monochromatic LEDs. For a Revision 3 product, these values are tightly controlled and specified within defined bins to ensure color and brightness consistency across production batches.

2.2 Electrical Parameters

Electrical parameters are crucial for circuit design. The forward voltage (Vf) is the voltage drop across the LED when operating at a specified forward current (If). It is typically specified at a standard test current (e.g., 20mA, 150mA, 350mA) and can have a range (e.g., 2.9V to 3.4V). The forward current is the recommended operating current for achieving the specified luminous output. Maximum ratings for reverse voltage (Vr), peak forward current, and power dissipation are also defined to prevent device failure. The stable revision indicates these parameters have been validated and are not subject to frequent change.

2.3 Thermal Characteristics

LED performance and lifespan are heavily influenced by temperature. The junction temperature (Tj) is the temperature at the semiconductor chip itself. The thermal resistance, junction-to-ambient (RθJA), measured in °C/W, indicates how effectively heat is transferred from the chip to the surrounding environment. A lower value signifies better heat dissipation. The maximum allowable junction temperature (Tj max) is a critical limit; exceeding it can lead to rapid lumen depreciation and reduced operational life. Proper heatsinking is essential to maintain Tj within safe limits.

3. Binning System Explanation

A binning system is used to categorize LEDs based on slight variations in manufacturing, grouping them into performance bands to ensure consistency for the end-user.

3.1 Wavelength/Color Temperature Binning

LEDs are sorted into bins based on their dominant wavelength (for colored LEDs) or correlated color temperature (for white LEDs). For example, white LEDs might be binned into 3000K, 4000K, and 5000K groups, each with a permissible range of +/- a few hundred Kelvin. This allows designers to select the precise color required for their application.

3.2 Luminous Flux Binning

LEDs are also binned according to their luminous flux output at a standard test current. Bins are defined by minimum and maximum lumen values. This ensures that products requiring a specific brightness level can be reliably sourced with components from the same flux bin.

3.3 Forward Voltage Binning

Forward voltage bins group LEDs with similar Vf characteristics. This is particularly important for designs where multiple LEDs are connected in series, as mismatched Vf values can lead to uneven current distribution and brightness variations.

4. Performance Curve Analysis

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

4.1 Current vs. Voltage (I-V) Curve

The I-V curve illustrates the relationship between the forward current and the forward voltage drop. It is non-linear, showing a threshold voltage below which very little current flows. The curve's slope in the operating region relates to the dynamic resistance of the LED. This graph is essential for designing the current-limiting circuitry.

4.2 Temperature Characteristics

Graphs typically show how forward voltage and luminous flux change with junction temperature. Forward voltage generally decreases with increasing temperature (negative temperature coefficient). Luminous flux output decreases as temperature rises; this relationship is plotted as relative luminous flux vs. junction temperature. Understanding this derating is key for thermal management design.

4.3 Spectral Power Distribution

For white LEDs, the SPD graph shows the intensity of light emitted at each wavelength across the visible spectrum. It reveals the peaks of the blue pump LED and the broad phosphor emission, helping to understand the light's color quality and CRI.

5. Mechanical and Package Information

The physical dimensions and construction of the LED package are defined here.

5.1 Outline Dimensions Drawing

A detailed mechanical drawing provides the exact length, width, height, and curvature of the LED package. It includes tolerances for all critical dimensions to ensure compatibility with automated placement equipment and optical systems.

5.2 Pad Layout and Solder Pad Design

The recommended footprint (land pattern) for the PCB is specified. This includes the size, shape, and spacing of the copper pads to which the LED's terminals will be soldered. Adhering to this design ensures proper solder joint formation, mechanical stability, and thermal conduction.

5.3 Polarity Identification

The method for identifying the anode (+) and cathode (-) terminals is clearly indicated. This is often done via a marking on the package (such as a notch, dot, or cut corner), a longer lead (for through-hole), or a specific pad shape/silkscreen on the PCB layout.

6. Soldering and Assembly Guidelines

Proper handling and soldering are vital for reliability.

6.1 Reflow Soldering Profile

A recommended reflow temperature profile is provided, including preheat, soak, reflow (peak temperature), and cooling stages. Maximum temperature limits and time-above-liquidus are specified to prevent thermal damage to the LED package, lens, or internal die attach materials.

6.2 Precautions and Handling

Guidelines cover protection from electrostatic discharge (ESD), which can damage the semiconductor junction. Recommendations for storage conditions (temperature, humidity) and shelf life are included. Instructions against applying mechanical stress to the lens are also typical.

6.3 Storage Conditions

LEDs should be stored in a controlled environment, typically at temperatures between 5°C and 30°C and at low humidity, often in moisture-barrier bags with desiccant if they are moisture-sensitive devices (MSD).

7. Packaging and Ordering Information

7.1 Packaging Specifications

The unit packaging (e.g., tape and reel for surface-mount devices, tubes, or trays) is described, including reel dimensions, pocket spacing, and orientation. Quantities per reel, tube, or bag are specified.

7.2 Labeling Information

The information printed on the packaging label is explained, which may include part number, bin code, lot number, date code, and quantity.

7.3 Part Numbering System

The model naming convention is decoded. A typical part number may include codes for the package type, color, flux bin, color temperature bin, voltage bin, and other special features, allowing precise ordering of the required specification.

8. Application Suggestions

8.1 Typical Application Circuits

Schematics for basic drive circuits are often included, such as a simple series resistor current limiter for low-power applications or constant current driver circuits for higher-power or precision applications. Considerations for series/parallel connections are discussed.

8.2 Design Considerations

Key design advice includes thermal management strategies (PCB copper area, thermal vias, external heatsinks), optical design (lens selection, spacing), and electrical design (matching drivers to LED forward voltage and current, inrush current protection, dimming compatibility).

9. Technical Comparison

While direct comparison requires a specific competitor, the advantages of a mature Revision 3 product generally include proven reliability, extensive field history, stable supply chain, comprehensive documentation, and well-understood performance characteristics. Potential trade-offs might include slightly less advanced performance metrics (e.g., lower lumens per watt) compared to the latest-generation components, but this is offset by predictability and lower risk in design.

10. Frequently Asked Questions

Q: What does "Lifecycle Phase: Revision 3" mean?
A: It indicates this is the third major revision of the product's documentation and specifications. The product design is stable, and changes are minimal, focusing on clarifications or minor improvements rather than fundamental redesigns.

Q: What is the implication of "Expired Period: Forever"?
A: This document does not have a planned obsolescence date. The specifications are intended to remain valid indefinitely, supporting long-term product designs and maintenance.

Q: Can I mix LEDs from different bins in the same product?
A: It is strongly discouraged for applications requiring uniform color or brightness. Mixing bins can lead to visible differences. Always specify and use LEDs from the same bin for consistent results.

Q: How critical is thermal management for this LED?
A: It is paramount for all power LEDs. Exceeding the maximum junction temperature will significantly reduce light output and operational lifespan. Always follow the thermal resistance guidelines and design an adequate heatsinking solution.

11. Practical Use Cases

Case 1: Architectural Linear Lighting: A Revision 3 LED is ideal for long-run cove lighting or facade illumination where color consistency from one end of the run to the other is critical. The stable binning and mature technology ensure minimal color shift over the lifetime of the installation.

Case 2: Industrial Panel Indicators: For status lights on machinery or control panels, reliability and long-term availability are key. Using a Revision 3 component ensures that replacement LEDs will have identical characteristics years later, maintaining the system's integrity.

Case 3: Retrofit LED Modules: When designing a module to replace traditional lighting (e.g., halogen MR16), the well-defined electrical and thermal parameters of a Revision 3 LED allow for precise driver matching and heatsink design, ensuring safe and efficient operation within enclosed fixtures.

12. Principle Introduction

Light Emitting Diodes (LEDs) are semiconductor devices that emit light when an electric current passes through them. This phenomenon, called electroluminescence, occurs when electrons recombine with electron 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. White LEDs are typically created by using a blue or ultraviolet LED chip coated with a phosphor material. The phosphor absorbs a portion of the chip's light and re-emits it at longer wavelengths (yellow, red), mixing with the remaining blue light to produce white. The specific materials, chip architecture, and phosphor formulation define the LED's efficiency, color quality, and reliability.

13. Development Trends

The solid-state lighting industry continues to evolve. Key trends include increasing luminous efficacy (lumens per watt), pushing the theoretical limits of semiconductor materials. There is a strong focus on improving color quality, with high-CRI (90+) and full-spectrum LEDs becoming more common for applications where accurate color rendering is essential. Miniaturization persists, enabling higher density and new form factors. Smart lighting integration, featuring built-in control and sensing, is a growing field. Furthermore, research into novel materials like perovskites and quantum dots promises future leaps in performance and color tuning capabilities. The trend also emphasizes sustainability, with goals for higher efficiency, longer lifespan, and reduced use of critical raw materials.