LED Component Datasheet - Revision 3 - Lifecycle Information - English Technical Document

1. Product Overview

This technical datasheet provides comprehensive information for an LED component, focusing on its lifecycle management and revision history. The document is essential for engineers, procurement specialists, and quality assurance teams to ensure the correct version of the component is used in design and production. The core advantage of this detailed lifecycle tracking is traceability and consistency in long-term projects, ensuring that specifications remain unchanged or are properly documented when revisions occur. The target market includes consumer electronics, automotive lighting, industrial indicators, and general illumination applications where component reliability and documentation are critical.

2. Lifecycle and Revision Information

The provided PDF content repeatedly indicates a consistent lifecycle status for the component.

2.1 Lifecycle Phase

The LifecyclePhase is documented as Revision: 3. This signifies that the component is in an active revision state, specifically the third major revision of its product documentation or specifications. A revision indicates updates to parameters, performance data, recommended usage, or packaging information from previous versions. It is crucial for users to reference this specific revision to ensure their designs align with the latest tested and validated data.

2.2 Validity and Release

The Expired Period is noted as Forever. This term typically indicates that this particular revision of the datasheet does not have a planned obsolescence date and is intended to remain valid indefinitely for reference purposes, unless superseded by a newer revision. The Release Date is precisely recorded as 2014-12-05 13:13:10.0. This timestamp provides an exact point of reference for when this third revision was officially issued and became the active document for the component.

3. Technical Parameters Deep Objective Interpretation

While the provided snippet focuses on lifecycle data, a complete LED datasheet would contain the following critical technical parameters. The values below are illustrative examples based on common industry standards for a mid-power LED; designers must consult the full, official datasheet for absolute values.

3.1 Photometric and Color Characteristics

These parameters define the light output and quality of the LED.

• Dominant Wavelength / Correlated Color Temperature (CCT): Specifies the perceived color of the light. For white LEDs, this is given in Kelvin (K), e.g., 2700K (Warm White), 4000K (Neutral White), 6500K (Cool White). For colored LEDs, it is given in nanometers (nm), e.g., 630nm (Red), 525nm (Green), 450nm (Blue).
• Luminous Flux: The total perceived power of light emitted, measured in lumens (lm). This is typically specified at a standard test current (e.g., 65mA, 150mA) and junction temperature (e.g., 25°C).
• Luminous Efficacy: The efficiency of the LED, calculated as lumens per watt (lm/W). Higher efficacy indicates better energy conversion from electrical power to visible light.
• Color Rendering Index (CRI): For white LEDs, CRI (Ra) measures the ability to reveal the colors of objects faithfully compared to a natural light source. A CRI above 80 is good for general lighting, while above 90 is excellent for applications requiring high color fidelity.

3.2 Electrical Parameters

These define the operating conditions and electrical limits of the LED.

• Forward Voltage (Vf): The voltage drop across the LED when operating at a specified forward current. It varies with current and temperature. Typical values range from 2.8V to 3.4V for white and blue LEDs, and 1.8V to 2.2V for red and amber LEDs.
• Forward Current (If): The recommended continuous DC operating current, e.g., 65mA, 150mA, 300mA. Exceeding the maximum rated current can cause permanent damage.
• Reverse Voltage (Vr): The maximum voltage that can be applied in the reverse direction without damaging the LED. This value is usually low (e.g., 5V).
• Power Dissipation: The maximum electrical power the package can handle, calculated as Vf * If, and limited by thermal constraints.

3.3 Thermal Characteristics

LED performance and lifespan are heavily dependent on thermal management.

• Thermal Resistance (Rth_j-s or Rth_j-c): The resistance to heat flow from the LED junction to the solder point (s) or case (c), measured in °C/W. A lower value indicates better heat dissipation capability.
• Maximum Junction Temperature (Tj_max): The highest allowable temperature at the semiconductor junction. Continuous operation above this limit drastically reduces lifetime and can cause immediate failure. Typical Tj_max is 120°C to 150°C.
• Temperature Coefficient of Forward Voltage: The rate at which Vf changes with junction temperature, typically around -2mV/°C to -4mV/°C.

4. Binning System Explanation

Manufacturing variations lead to slight differences between individual LEDs. Binning groups LEDs with similar characteristics to ensure consistency in mass production.

4.1 Wavelength / Color Temperature Binning

LEDs are sorted into bins based on their dominant wavelength (color) or CCT. For white LEDs, bins may represent steps of 100K or 200K within a nominal CCT range (e.g., 6500K ± 300K). Using LEDs from a single bin or adjacent bins is critical for applications requiring uniform color appearance.

4.2 Luminous Flux Binning

LEDs are binned according to their light output at a standard test condition. Bins are defined as minimum flux values or percentage ranges (e.g., Bin A: 100-105 lm, Bin B: 105-110 lm). This allows designers to select the brightness grade suitable for their cost and performance targets.

4.3 Forward Voltage Binning

Sorting by forward voltage (Vf) at a specific current helps in designing efficient driver circuits, especially when connecting multiple LEDs in series. Matching Vf bins can improve current balance in parallel strings.

5. Performance Curve Analysis

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

5.1 Current-Voltage (I-V) Characteristic Curve

This curve shows the relationship between forward current (If) and forward voltage (Vf). It is non-linear, with a sharp increase in current once the voltage exceeds the diode's threshold. The curve shifts with temperature. This graph is essential for driver design to ensure stable current control.

5.2 Temperature Characteristics

Key graphs include Luminous Flux vs. Junction Temperature and Forward Voltage vs. Junction Temperature. Luminous flux typically decreases as temperature increases. Understanding this derating is vital for thermal design to maintain target light output in the application's operating environment.

5.3 Spectral Power Distribution (SPD)

The SPD graph shows the relative intensity of light emitted at each wavelength. For white LEDs, it reveals the blend of the blue pump LED and phosphor emissions. This graph is used for precise color analysis and calculating metrics like CRI and CCT.

6. Mechanical and Packaging Information

Physical specifications ensure proper PCB design and assembly.

6.1 Dimensional Outline Drawing

A detailed diagram showing the LED package's exact dimensions, including length, width, height, and any lens curvature. Critical tolerances are indicated. Common package sizes include 2835 (2.8mm x 3.5mm), 3535, 5050, etc.

6.2 Pad Layout Design

The recommended solder pad pattern on the PCB, including pad size, shape, and spacing. Following this layout ensures good solder joint reliability, proper heat sinking, and prevents tombstoning during reflow.

6.3 Polarity Identification

Clear marking of the anode (+) and cathode (-) terminals on the LED package, typically via a notch, cut corner, or marker on the cathode side. The datasheet will illustrate this marking.

7. Soldering and Assembly Guidelines

7.1 Reflow Soldering Profile

A recommended time-temperature profile for reflow soldering, including preheat, soak, reflow, and cooling zones. Maximum peak temperature (usually 260°C for a few seconds) and time above liquidus (TAL) are specified to prevent thermal damage to the LED package and internal materials.

7.2 Precautions

• Avoid mechanical stress on the LED lens.
• Use no-clean or mildly activated fluxes suitable for LEDs.
• Do not clean with ultrasonic methods as they can damage the phosphor layer.
• Prevent electrostatic discharge (ESD) during handling.

7.3 Storage Conditions

LEDs should be stored in a dry, dark environment at recommended temperature and humidity (e.g., <40°C, <60% RH). They are often shipped in moisture-sensitive device (MSD) packaging with a humidity indicator card. If exposed, baking may be required before reflow to prevent "popcorning."

8. Packaging and Ordering Information

8.1 Packaging Specifications

Details on reel type (e.g., 12mm, 16mm), reel dimensions, pocket quantity, and orientation. Tape-and-reel specifications follow standards like EIA-481.

8.2 Label Explanation

Information on the reel label, including part number, quantity, lot number, date code, and bin codes for flux, color, and Vf.

8.3 Model Numbering Rule

Explanation of the part number structure, which typically encodes key attributes like package size, color/CCT, flux bin, voltage bin, and sometimes special features (e.g., high CRI).

9. Application Recommendations

9.1 Typical Application Scenarios

• General Lighting: LED bulbs, tubes, panels, downlights.
• Backlighting: TV, monitor, laptop, and signage backlight units.
• Automotive: Interior lighting, daytime running lights (DRLs), signal lights.
• Indicators & Signage: Status indicators, exit signs, channel letters.

9.2 Design Considerations

• Thermal Management: Design PCB with adequate thermal vias and copper area. Consider the thermal path to the heatsink.
• Driver Selection: Use a constant current driver matched to the LED's Vf and If requirements. Consider dimming method (PWM, analog) if needed.
• Optical Design: Select appropriate secondary optics (lenses, reflectors) to achieve the desired beam angle and distribution.
• Color Consistency: Specify tight binning requirements or use color mixing techniques for applications demanding high uniformity.

10. Technical Comparison

Compared to previous generations (e.g., Revision 2), Revision 3 of this datasheet may include updated performance data reflecting manufacturing process improvements, such as higher typical luminous flux or efficacy at the same current. It may also feature expanded or clarified maximum ratings, revised test conditions, or more detailed application notes. The primary differentiation from generic or competitor parts lies in the specific combination of performance parameters (efficacy, CRI, reliability), package robustness, and the depth and accuracy of the provided technical data, which enables more precise and reliable design.

11. Frequently Asked Questions (FAQs)

11.1 What does "LifecyclePhase: Revision 3" mean?

It indicates this is the third officially released version of the component's datasheet. Any technical changes from previous revisions are documented here. Always use the latest revision for new designs.

11.2 How should I interpret "Expired Period: Forever"?

This datasheet revision is considered permanently valid for reference unless explicitly replaced by a newer revision (e.g., Revision 4). It does not mean the component itself is in production forever.

11.3 Can I mix LEDs from different flux or color bins in my product?

It is not recommended for final products as it will cause visible brightness and color differences. For prototyping, ensure bins are documented. For production, specify a single bin or mixing rules from your supplier.

11.4 What happens if I operate the LED above the maximum junction temperature?

Operating above Tj_max accelerates lumen depreciation (light output loss) and can lead to catastrophic failure through mechanisms like phosphor degradation or bond wire failure. Proper heatsinking is non-negotiable.

12. Practical Use Case

Case Study: Designing a Linear LED Fixture
An engineer is designing a 4-foot LED tube light for office lighting. Using this datasheet (Revision 3), they select a neutral white (4000K) LED with a high CRI (Ra>90) from a specific flux bin to meet the target lumens per fixture. The I-V curve and thermal resistance data are used to design a series-parallel array and select a suitable constant current driver. The mechanical drawing ensures the PCB layout has correct pad sizes. The reflow profile is programmed into the SMT machine. By adhering to the storage and handling precautions, they achieve a high first-pass yield during manufacturing. The fixture's performance is consistent and meets the specified lifetime (L70) because the thermal management design keeps the junction temperature well below the maximum rating under all operating conditions.

13. 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. White LEDs are typically created by combining a blue or ultraviolet LED chip with a phosphor coating that converts some of the emitted light to longer wavelengths (yellow, red), resulting in a broad spectrum perceived as white light. The efficiency, color, and longevity of an LED are influenced by the semiconductor materials, chip architecture, phosphor composition, and package design.

14. Development Trends

The LED industry continues to evolve with several clear trends. Efficiency (lm/W) is steadily increasing, reducing energy consumption for the same light output. There is a strong focus on improving color quality, including higher CRI values and better consistency in color rendering across different spectra (e.g., R9 for reds). Miniaturization of packages while maintaining or increasing light output is ongoing. Smart and connected lighting, integrating drivers with control circuitry for tunable white (CCT adjustment) and full-color capabilities, is becoming more prevalent. Furthermore, reliability and lifetime under high-temperature operating conditions are constantly being enhanced through improved materials and packaging technologies. The industry also sees a push towards standardization of performance reporting and testing conditions to allow for more accurate comparisons between products from different manufacturers.