LED Component Technical Datasheet - Revision 2 - Lifecycle: Forever - Release Date: 2014-11-28 - English Technical Documentation

1. Product Overview

This document provides comprehensive technical specifications and application guidelines for a specific LED component. The core information establishes the document's validity and revision status. The lifecycle phase is confirmed as Revision 2, indicating this is the second official revision of the component's technical data. The release date for this revision is November 28, 2014, at 10:08:02. Crucially, the expired period is marked as Forever, signifying that the specifications contained within this revision are considered permanently valid and are not subject to scheduled obsolescence or automatic supersession by a newer revision date. This permanence is a key characteristic for long-term design and manufacturing planning.

The component is designed for reliability and consistent performance. Its target market includes applications requiring stable, long-term optical output, such as general lighting, indicator lights, backlighting for displays, and automotive interior lighting. The core advantage lies in the frozen specification set, allowing engineers to design systems with confidence that the component's key parameters will not change unexpectedly in future production batches.

2. In-Depth Technical Parameter Analysis

While the provided excerpt focuses on document metadata, a complete technical datasheet for an LED component would contain detailed objective parameters. The following sections outline the critical data typically included and their significance.

2.1 Photometric and Color Characteristics

The photometric properties define the light output of the LED. Key parameters include:

• Luminous Flux (Φ_v): Measured in lumens (lm), this indicates the total perceived power of light emitted. Datasheets often provide typical and minimum values at a specified test current (e.g., 20mA, 60mA) and junction temperature (T_j).
• Luminous Intensity (I_v): Measured in millicandelas (mcd), this describes the luminous power per unit solid angle. It is crucial for directional lighting applications. The viewing angle is specified alongside this parameter (e.g., 120°).
• Dominant Wavelength (λ_D) or Correlated Color Temperature (CCT): For colored LEDs (Red, Green, Blue, Amber), the dominant wavelength defines the perceived color. For white LEDs, the Correlated Color Temperature (measured in Kelvin, K) specifies whether the light appears warm (e.g., 2700K), neutral (e.g., 4000K), or cool (e.g., 6500K).
• Color Rendering Index (CRI - R_a): For white LEDs, CRI indicates how accurately the light source reveals the colors of objects compared to a natural light source. A higher CRI (closer to 100) is better for applications where color discrimination is important.

2.2 Electrical Parameters

These parameters govern the electrical drive requirements and power consumption.

• Forward Voltage (V_F): The voltage drop across the LED when operating at a specified forward current (I_F). It is typically given as a range (e.g., 2.8V to 3.4V at 20mA). This parameter is essential for designing the current-limiting circuitry or selecting an appropriate driver.
• Forward Current (I_F): The recommended continuous operating current. Exceeding the maximum rated forward current can drastically reduce lifespan or cause immediate failure.
• Reverse Voltage (V_R): The maximum voltage the LED can withstand when connected in reverse bias. Exceeding this voltage can cause irreversible damage.

2.3 Thermal Characteristics

LED performance and longevity are highly dependent on temperature management.

• Junction Temperature (T_j): The temperature at the semiconductor chip itself. The maximum allowable T_j (e.g., 125°C) is a critical design limit.
• Thermal Resistance (R_θJA): Measured in °C/W, this indicates how effectively heat travels from the LED junction to the ambient air. A lower value means better heat dissipation, which is vital for maintaining light output and lifespan.
• Storage Temperature Range: The allowable temperature range for the component when not powered.

3. Binning System Explanation

Due to manufacturing variations, LEDs are sorted into performance bins. This ensures customers receive components within a specified tolerance.

• Wavelength/Color Temperature Binning: LEDs are grouped based on their measured dominant wavelength or CCT. A bin code (e.g., "3A") corresponds to a specific wavelength range (e.g., 525-530nm).
• Luminous Flux Binning: LEDs are sorted according to their light output at a standard test condition. This allows designers to select components that meet minimum brightness requirements for their application.
• Forward Voltage Binning: Sorting by V_F range helps in designing more uniform current distribution when multiple LEDs are connected in series.

4. Performance Curve Analysis

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

• I-V (Current-Voltage) Curve: This graph shows the relationship between forward current and forward voltage. It is non-linear, characteristic of a diode. The curve helps in understanding the dynamic resistance of the LED.
• Temperature Characteristics: Graphs typically show how luminous flux or forward voltage changes with increasing junction temperature. Luminous flux generally decreases as temperature rises.
• Relative Spectral Power Distribution: This plot shows the intensity of light emitted at each wavelength. It defines the color characteristics and can show the presence of secondary peaks (e.g., in phosphor-converted white LEDs).

5. Mechanical and Package Information

Physical specifications are critical for PCB design and assembly.

• Package Dimensions: Detailed mechanical drawings specifying the length, width, height, and any lens curvature. Tolerances are always provided.
• Pad Layout (Footprint): The recommended copper pad pattern on the PCB for soldering. This includes pad size, shape, and spacing to ensure proper solder joint formation and mechanical stability.
• Polarity Identification: Clear marking of the anode (+) and cathode (-) terminals. This is usually indicated by a notch, a cut corner, a mark on the lens, or different lead lengths.

6. Soldering and Assembly Guidelines

Proper handling ensures reliability.

• Reflow Soldering Profile: A time-temperature graph specifying the recommended preheat, soak, reflow, and cooling phases. Critical parameters include peak temperature (typically 260°C maximum for a few seconds) and time above liquidus.
• Handling Precautions: Instructions regarding ESD (Electrostatic Discharge) sensitivity, moisture sensitivity level (MSL), and recommendations for storage (often in dry cabinets if MSL > 1).
• Cleaning: Compatibility with common PCB cleaning solvents.

7. Packaging and Ordering Information

Information for procurement and logistics.

• Packaging Specification: Describes the carrier tape width, pocket dimensions, reel diameter, and quantity per reel (e.g., 4000 pieces per 13-inch reel).
• Labeling: Explains the information printed on the reel label, including part number, quantity, date code, and bin codes.
• Part Numbering System: Decodes the part number to indicate key attributes like color, brightness bin, voltage bin, and package type.

8. Application Recommendations

Guidance for implementing the component effectively.

• Typical Application Circuits: Schematics showing constant current driver circuits, series/parallel resistor calculations, and protection elements like transient voltage suppressors.
• Design Considerations: Advice on thermal management (PCB copper area, heatsinking), optical design (lens selection for desired beam pattern), and derating guidelines for high-temperature environments.
• Typical Use Cases:

  Based on the permanent revision status and common LED characteristics, this component is suitable for products with long lifecycles or where design stability is paramount. Examples include:

  • Industrial Control Panels: Status indicators on machinery that may be in service for decades.
  • Infrastructure Lighting: Exit signs, emergency lighting, or architectural accents where maintenance and part replacement are difficult.
  • Consumer Appliances: Power-on indicators or backlights for controls on devices like refrigerators or ovens.
  • Automotive Interior Lighting: Map lights, dashboard backlighting, or switch illumination where color and brightness consistency are important over the vehicle's lifespan.

  9. Technical Comparison and Differentiation

  The primary differentiator highlighted by the provided data is the "Forever" expired period. Many electronic components have datasheets tied to a specific revision that may be updated frequently. This component's documentation is declared permanently valid (Revision 2). This offers significant advantages:

  • Long-Term Supply Assurance: Manufacturers can stockpile or plan long production runs without fear of specification changes.
  • Design Stability: Products designed around this component will not require re-validation or re-certification due to a datasheet change.
  • Reduced Risk: Eliminates the risk of subtle performance shifts between revisions affecting end-product quality or compliance.

  Compared to components with frequently updated datasheets, this one prioritizes absolute consistency over potential incremental performance improvements.

  10. Frequently Asked Questions (Based on Technical Parameters)

  Q: What does "LifecyclePhase: Revision" mean?
  A: It indicates the document's stage in its control process. "Revision" means this is an updated version (Revision 2) of a previously released datasheet, containing potentially corrected or enhanced information.

  Q: The release date is 2014. Is this component obsolete?
  A: Not necessarily. The "Expired Period: Forever" explicitly states the specifications are permanently valid. The component may still be in active production. Its relevance depends on whether its technical parameters meet current application needs.

  Q: How should I drive this LED?
  A> You must use a constant current source or a voltage source with a series current-limiting resistor. The exact circuit depends on the forward voltage (V_F) and forward current (I_F) specifications, which would be detailed in the full datasheet. Never connect an LED directly to a voltage source without current control.

  Q: Why is thermal management important for LEDs?
  A> High junction temperature accelerates the degradation of the semiconductor material and the phosphor (in white LEDs), leading to a permanent decrease in light output (lumen depreciation) and a potential shift in color. It can also cause catastrophic failure. Proper heatsinking is essential for performance and longevity.

  11. Practical Design and Usage Case Study

  Scenario: Designing a long-life industrial status indicator panel.

  An engineer is designing a control panel for industrial equipment expected to have a 20-year service life. The panel requires red, green, and yellow status LEDs. Consistency and reliability are critical.

  Selection Rationale: The engineer selects this specific LED component (Revision 2, Forever valid) for the following reasons:

  1. Specification Guarantee: The permanent datasheet ensures that LEDs purchased for initial production and for spare parts/service kits in year 15 will have identical performance specifications, maintaining panel uniformity.
  2. Supply Chain Planning: The company can make a long-term purchase agreement with the distributor, confident that the part won't be "improved" in a way that requires a redesign.
  3. Design Implementation: Using the detailed V_F and I_F data, the engineer designs a simple resistor-based drive circuit for each LED color on the PCB. The thermal resistance (R_θJA) data is used to calculate that the small amount of heat generated will be safely dissipated by the PCB copper, ensuring the junction temperature remains well below the maximum rating even in the equipment's 50°C ambient environment.
  4. Result: The final product benefits from stable, predictable indicator performance throughout its entire operational life, reducing warranty claims and maintenance complexity.

  12. Operating Principle Introduction

  An LED (Light Emitting Diode) is a semiconductor device that emits light when an electric current passes through it. The core principle is electroluminescence.

  1. A semiconductor chip contains a p-n junction, where p-type material (with electron holes) meets n-type material (with free electrons).
  2. When a forward voltage is applied (positive to the p-side, negative to the n-side), electrons from the n-region gain enough energy to cross the junction and recombine with holes in the p-region.
  3. This recombination process releases energy. In standard diodes, this energy is released as heat. In LEDs, the semiconductor materials (like Gallium Nitride for blue/white, or Gallium Arsenide Phosphide for red/yellow) are chosen so that this energy is released primarily as photons (light particles).
  4. The wavelength (color) of the emitted light is determined by the energy band gap of the semiconductor material. A larger band gap produces higher-energy photons (shorter wavelength, like blue light). White LEDs typically use a blue LED chip coated with a yellow phosphor; some of the blue light is converted to yellow, and the mixture is perceived as white.

  13. Technology Trends and Developments

  The LED industry continues to evolve, though a component with a permanently frozen datasheet represents a mature, stabilized technology point. General trends observable in the broader market include:

  • Increased Efficiency (lm/W): Ongoing improvements in internal quantum efficiency and light extraction techniques lead to more lumens per watt of electrical input, reducing energy consumption for the same light output.
  • Improved Color Quality: Development of new phosphor systems for white LEDs leads to higher Color Rendering Index (CRI) values and more consistent color temperature across production bins.
  • Miniaturization: Continued reduction in package size (e.g., from 3528 to 2016 to 1010 metric codes) enabling higher-density lighting arrays and integration into smaller devices.
  • Higher Power Density: Development of high-power LED packages capable of handling currents of 1A, 3A, or more, often requiring sophisticated active cooling solutions.
  • Smart and Connected Lighting: Integration of control electronics, sensors, and communication interfaces (like Zigbee or Bluetooth) directly into LED modules, moving beyond simple components towards intelligent lighting systems.

  The component described in this document, with its permanent revision, sits as a reliable, well-characterized building block within this evolving technological landscape, chosen for applications where proven consistency outweighs the latest performance metrics.

  LED Specification Terminology

  Complete explanation of LED technical terms

  Photoelectric Performance

  Term	Unit/Representation	Simple Explanation	Why Important
  Luminous Efficacy	lm/W (lumens per watt)	Light output per watt of electricity, higher means more energy efficient.	Directly determines energy efficiency grade and electricity cost.
  Luminous Flux	lm (lumens)	Total light emitted by source, commonly called "brightness".	Determines if the light is bright enough.
  Viewing Angle	° (degrees), e.g., 120°	Angle where light intensity drops to half, determines beam width.	Affects illumination range and uniformity.
  CCT (Color Temperature)	K (Kelvin), e.g., 2700K/6500K	Warmth/coolness of light, lower values yellowish/warm, higher whitish/cool.	Determines lighting atmosphere and suitable scenarios.
  CRI / Ra	Unitless, 0–100	Ability to render object colors accurately, Ra≥80 is good.	Affects color authenticity, used in high-demand places like malls, museums.
  SDCM	MacAdam ellipse steps, e.g., "5-step"	Color consistency metric, smaller steps mean more consistent color.	Ensures uniform color across same batch of LEDs.
  Dominant Wavelength	nm (nanometers), e.g., 620nm (red)	Wavelength corresponding to color of colored LEDs.	Determines hue of red, yellow, green monochrome LEDs.
  Spectral Distribution	Wavelength vs intensity curve	Shows intensity distribution across wavelengths.	Affects color rendering and quality.

  Electrical Parameters

  Term	Symbol	Simple Explanation	Design Considerations
  Forward Voltage	Vf	Minimum voltage to turn on LED, like "starting threshold".	Driver voltage must be ≥Vf, voltages add up for series LEDs.
  Forward Current	If	Current value for normal LED operation.	Usually constant current drive, current determines brightness & lifespan.
  Max Pulse Current	Ifp	Peak current tolerable for short periods, used for dimming or flashing.	Pulse width & duty cycle must be strictly controlled to avoid damage.
  Reverse Voltage	Vr	Max reverse voltage LED can withstand, beyond may cause breakdown.	Circuit must prevent reverse connection or voltage spikes.
  Thermal Resistance	Rth (°C/W)	Resistance to heat transfer from chip to solder, lower is better.	High thermal resistance requires stronger heat dissipation.
  ESD Immunity	V (HBM), e.g., 1000V	Ability to withstand electrostatic discharge, higher means less vulnerable.	Anti-static measures needed in production, especially for sensitive LEDs.

  Thermal Management & Reliability

  Term	Key Metric	Simple Explanation	Impact
  Junction Temperature	Tj (°C)	Actual operating temperature inside LED chip.	Every 10°C reduction may double lifespan; too high causes light decay, color shift.
  Lumen Depreciation	L70 / L80 (hours)	Time for brightness to drop to 70% or 80% of initial.	Directly defines LED "service life".
  Lumen Maintenance	% (e.g., 70%)	Percentage of brightness retained after time.	Indicates brightness retention over long-term use.
  Color Shift	Δu′v′ or MacAdam ellipse	Degree of color change during use.	Affects color consistency in lighting scenes.
  Thermal Aging	Material degradation	Deterioration due to long-term high temperature.	May cause brightness drop, color change, or open-circuit failure.

  Packaging & Materials

  Term	Common Types	Simple Explanation	Features & Applications
  Package Type	EMC, PPA, Ceramic	Housing material protecting chip, providing optical/thermal interface.	EMC: good heat resistance, low cost; Ceramic: better heat dissipation, longer life.
  Chip Structure	Front, Flip Chip	Chip electrode arrangement.	Flip chip: better heat dissipation, higher efficacy, for high-power.
  Phosphor Coating	YAG, Silicate, Nitride	Covers blue chip, converts some to yellow/red, mixes to white.	Different phosphors affect efficacy, CCT, and CRI.
  Lens/Optics	Flat, Microlens, TIR	Optical structure on surface controlling light distribution.	Determines viewing angle and light distribution curve.

  Quality Control & Binning

  Term	Binning Content	Simple Explanation	Purpose
  Luminous Flux Bin	Code e.g., 2G, 2H	Grouped by brightness, each group has min/max lumen values.	Ensures uniform brightness in same batch.
  Voltage Bin	Code e.g., 6W, 6X	Grouped by forward voltage range.	Facilitates driver matching, improves system efficiency.
  Color Bin	5-step MacAdam ellipse	Grouped by color coordinates, ensuring tight range.	Guarantees color consistency, avoids uneven color within fixture.
  CCT Bin	2700K, 3000K etc.	Grouped by CCT, each has corresponding coordinate range.	Meets different scene CCT requirements.

  Testing & Certification

  Term	Standard/Test	Simple Explanation	Significance
  LM-80	Lumen maintenance test	Long-term lighting at constant temperature, recording brightness decay.	Used to estimate LED life (with TM-21).
  TM-21	Life estimation standard	Estimates life under actual conditions based on LM-80 data.	Provides scientific life prediction.
  IESNA	Illuminating Engineering Society	Covers optical, electrical, thermal test methods.	Industry-recognized test basis.
  RoHS / REACH	Environmental certification	Ensures no harmful substances (lead, mercury).	Market access requirement internationally.
  ENERGY STAR / DLC	Energy efficiency certification	Energy efficiency and performance certification for lighting.	Used in government procurement, subsidy programs, enhances competitiveness.