LED Component Lifecycle Document - Revision 4 - Release Date 2013-06-10 - English Technical Specification

1. Product Overview

This technical document provides comprehensive information regarding the lifecycle status and revision history of a specific LED (Light Emitting Diode) component. The core focus is on the formal declaration of the component's current revision phase, its release timeline, and the associated validity period. Understanding this information is critical 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 establishes a single source of truth for the component's approved technical state at the time of release.

The primary advantage conveyed by this document is clarity and traceability. By explicitly stating the Lifecycle Phase as \"Revision 4\" and providing a precise Release Date, it eliminates ambiguity about which version of the component's specifications is current and valid. The declaration of an \"Expired Period: Forever\" indicates that this revision does not have a predetermined end-of-life date, suggesting its specifications are intended to remain stable and available for the foreseeable future, barring any fundamental technological or safety-related changes. This stability is a significant benefit for long-term product designs and supply chain planning.

2. Technical Parameter Deep Objective Interpretation

While the provided PDF excerpt focuses on administrative and lifecycle data, a complete technical document for an LED component would typically include several key parameter sections. These sections provide the objective, measurable data necessary for circuit design and system integration.

2.1 Photometric and Color Characteristics

This section details the light output and color properties of the LED. Key parameters include Luminous Flux, measured in lumens (lm), which quantifies the perceived power of light. The correlated Color Temperature (CCT), measured in Kelvin (K), defines whether the light appears warm (lower K, e.g., 2700K) or cool (higher K, e.g., 6500K). For colored LEDs, the Dominant Wavelength is specified in nanometers (nm). Chromaticity coordinates (e.g., CIE x, y) provide a precise, objective definition of the color point on the standard color space diagram. These parameters are typically presented with minimum, typical, and maximum values under specified test conditions (e.g., forward current, junction temperature).

2.2 Electrical Parameters

The electrical characteristics define the operating boundaries and performance under electrical stress. The most critical parameter is the Forward Voltage (Vf), specified at a given test current (e.g., 20mA, 150mA). This voltage drop across the LED is essential for designing the current-limiting circuitry, such as resistor values or constant-current driver specifications. The Reverse Voltage (Vr) rating indicates the maximum voltage the LED can withstand in the non-conducting direction before breakdown occurs. Other parameters may include the maximum Continuous Forward Current and the Peak Forward Current for pulsed operation.

2.3 Thermal Characteristics

LED performance and longevity are heavily influenced by temperature. The key parameter here is the Thermal Resistance, Junction-to-Ambient (RθJA), expressed in degrees Celsius per watt (°C/W). This value indicates how effectively heat generated at the LED's semiconductor junction is dissipated to the surrounding environment. A lower RθJA signifies better heat dissipation. The Maximum Junction Temperature (Tj max) is the absolute highest temperature the semiconductor material can endure without permanent degradation or failure. Proper heat sinking is calculated based on these values to ensure Tj remains within safe limits during operation.

3. Binning System Explanation

Due to inherent variations in semiconductor manufacturing, LEDs are sorted into performance bins. This system ensures consistency for the end-user.

3.1 Wavelength/Color Temperature Binning

LEDs are binned according to their dominant wavelength or CCT. For white LEDs, this is often a MacAdam ellipse step system (e.g., 3-step, 5-step), defining how closely grouped the color points are on the chromaticity diagram. A smaller step number indicates tighter color consistency.

3.2 Luminous Flux Binning

LEDs are categorized based on their light output at a standard test current. Bins are defined by a minimum and maximum luminous flux value (e.g., Bin A: 100-110 lm, Bin B: 111-120 lm). This allows designers to select components that meet specific brightness requirements.

3.3 Forward Voltage Binning

To aid in circuit design and power supply sizing, LEDs may also be binned by their forward voltage drop at a specified current. This helps in predicting power consumption and ensuring uniform brightness in arrays powered by a common voltage source.

4. Performance Curve Analysis

Graphical data provides a deeper understanding of LED behavior beyond single-point specifications.

4.1 Current-Voltage (I-V) Characteristic Curve

This curve plots the forward current against the forward voltage. It shows the non-linear relationship where the LED begins to conduct significantly (the \"knee\" voltage). The curve's slope in the operating region relates to the dynamic resistance. This graph is essential for designing drivers that operate efficiently across a range of conditions.

4.2 Temperature Dependency

Curves typically show how forward voltage decreases with increasing junction temperature (for a constant current) and how luminous flux degrades as temperature rises. Understanding this thermal derating is crucial for designing systems that maintain consistent performance in different ambient conditions.

4.3 Spectral Power Distribution (SPD)

This graph plots the relative intensity of light emitted across the visible spectrum (and sometimes beyond). For white LEDs, it reveals the blend of the blue pump LED and the phosphor emission. The SPD determines the Color Rendering Index (CRI) and the precise color quality of the light.

5. Mechanical and Packaging Information

This section provides the physical dimensions and assembly details.

5.1 Outline Dimensions Drawing

A detailed mechanical drawing shows the LED package's exact length, width, height, and any critical features like lens shape or mounting tabs. All dimensions include tolerances.

5.2 Pad Layout and Footprint Design

The recommended printed circuit board (PCB) land pattern (footprint) is provided. This includes the size, shape, and spacing of the copper pads to which the LED's terminals will be soldered, ensuring proper mechanical attachment and thermal connection.

3.3 Polarity Identification

The method for identifying the anode (+) and cathode (-) terminals is clearly indicated, often through a diagram showing a notch, a cut corner, a marking on the package, or different lead lengths.

6. Soldering and Assembly Guidelines

Proper handling ensures reliability.

6.1 Reflow Soldering Profile

A time-temperature graph specifies the recommended reflow profile, including preheat, soak, reflow peak temperature, and cooling rates. Maximum temperature limits are given to prevent damage to the LED package or internal materials.

6.2 Precautions and Handling

Instructions cover electrostatic discharge (ESD) protection requirements, as LEDs are sensitive to voltage spikes. Guidelines for cleaning agents compatible with the package material may also be included.

6.3 Storage Conditions

Recommended temperature and humidity ranges for long-term storage of unused components are specified to prevent moisture absorption (which can cause \"popcorning\" during reflow) or other degradation.

7. Packaging and Ordering Information

Details on how the components are supplied.

7.1 Packaging Specifications

Describes the carrier medium, such as tape-and-reel dimensions, reel quantities, or tray specifications. This information is vital for automated assembly equipment setup.

7.2 Labeling Information

Explains the data printed on the packaging labels, which typically includes part number, quantity, lot/batch code, and date code for traceability.

7.3 Part Numbering System

Decodes the part number structure, showing how different fields correspond to attributes like color, flux bin, voltage bin, packaging type, and special features. This allows for precise ordering.

8. Application Recommendations

Guidance for implementing the component.

8.1 Typical Application Circuits

Schematics for basic drive circuits are often provided, such as a simple series resistor circuit for low-current applications or connections to constant-current driver ICs for higher-power or precision applications.

8.2 Design Considerations

Key points include the necessity of current regulation (not voltage regulation) for stable light output, the importance of thermal management through PCB copper area or external heatsinks, and optical considerations like viewing angle for the intended application.

9. Technical Comparison

While a specific datasheet may not list competitors, the inherent advantages of the component technology can be discussed. For instance, the LED documented here, being at a stable \"Revision 4\" lifecycle phase, offers the advantage of mature, well-characterized performance and predictable long-term availability compared to a brand-new, unproven revision (Rev 0 or 1). This reduces design risk and qualification effort for the end customer.

10. Frequently Asked Questions (FAQ)

Based on common technical parameter inquiries.

Q: What does \"LifecyclePhase: Revision\" mean?
A: It indicates the component is in a state of having undergone updates or corrections to its specification. \"Revision 4\" is the fourth such version, implying a mature and iteratively improved design.

Q: What is the implication of \"Expired Period: Forever\"?
A: This suggests the manufacturer does not currently plan to declare this specific revision obsolete or end its life. The specifications are intended to remain valid indefinitely, supporting long-term product designs. However, \"Forever\" is a commercial term and may be subject to change with significant notice.

Q: How critical is the Release Date?
A: Very. It establishes a baseline. Any components ordered or designs created after this date should reference this revision. It is a key element for version control and ensuring all parties in the supply chain are aligned on the exact specification in use.

11. Practical Use Cases

A component with a stable, long-life revision status is ideal for applications requiring long-term support and minimal requalification. Examples include industrial control panel indicators, emergency exit signs, infrastructure lighting (e.g., in bridges or tunnels), and medical device status lights. In these fields, product lifecycles can span decades, and the ability to source the exact same component years later is paramount for maintenance, repair, and regulatory compliance.

12. Principle Introduction

A Light Emitting Diode (LED) is a semiconductor device that emits light when an electric current passes through it. 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 coating a blue or ultraviolet LED with a phosphor material, which absorbs some of the LED's light and re-emits it at different wavelengths, creating a broad-spectrum white light.

13. Development Trends

The solid-state lighting industry continues to evolve with several clear trends. Efficiency, measured in lumens per watt (lm/W), continues to improve, reducing energy consumption for the same light output. Color quality metrics, like Color Rendering Index (CRI) and newer measures such as TM-30, are becoming more stringent, driving improvements in phosphor technology and multi-chip designs. Miniaturization persists, enabling new form factors in displays and ultra-compact lighting. Finally, smart and connected lighting, integrating sensors and communication protocols, is expanding the functionality of LEDs beyond simple illumination into areas of data transmission, human-centric lighting, and IoT integration.