LED Component Technical Datasheet - Lifecycle Revision 2 - Release Date 2014-12-05 - English Technical Document

1. Product Overview

This technical document pertains to a specific electronic component, likely an LED (Light Emitting Diode) or a related optoelectronic device. The core information provided establishes the document's validity and revision status. The component is in the "Revision" phase of its lifecycle, indicating it is an updated version of a previous design. The revision number is 2. The document itself was released on December 5, 2014, at 11:55:06 AM. Notably, the "Expired Period" is listed as "Forever," which suggests this document version is intended to remain the definitive reference for this specific revision of the component and does not have a planned obsolescence date for its technical content. This is common for finalized product datasheets that define a specific, fixed version of a hardware component.

2. Technical Parameters Deep Objective Interpretation

While the provided PDF excerpt is limited to metadata, a comprehensive technical datasheet for such a component would typically include the following parameter categories. The values below are illustrative examples based on common industry standards for components from this era and should be verified against the full, original datasheet for the specific part number.

2.1 Photometric and Color Characteristics

These parameters define the light output and color of the device.

• Dominant Wavelength / Correlated Color Temperature (CCT): For colored LEDs (e.g., red, blue, green), the peak wavelength is specified (e.g., 625nm ± 5nm). For white LEDs, the color temperature is given (e.g., 4000K, 5000K, 6500K).
• Luminous Flux: The total visible light output, measured in lumens (lm). A typical mid-power LED from 2014 might offer 20-30 lumens at a standard test current.
• Luminous Efficacy: The efficiency of converting electrical power to visible light, measured in lumens per watt (lm/W). For 2014-era LEDs, efficacies in the range of 100-130 lm/W were common for high-quality white LEDs.
• Color Rendering Index (CRI): For white LEDs, this measures the quality of light and its ability to reveal the true colors of objects. A CRI above 80 is typical for general lighting, with high-CRI variants offering 90+.

2.2 Electrical Parameters

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

• Forward Voltage (Vf): The voltage drop across the LED when operating at its specified current. This is highly dependent on the LED chip technology and color. For example, a typical white LED might have a Vf of 2.8V to 3.4V at 350mA.
• Forward Current (If): The recommended operating current. Common values are 150mA, 350mA, or 700mA for power LEDs. Exceeding the maximum rated current can cause permanent damage.
• Reverse Voltage (Vr): The maximum voltage the LED can withstand when connected in reverse bias without breaking down. This is typically quite low (e.g., 5V).
• Power Dissipation: The maximum electrical power the package can handle, calculated as Vf * If, and limited by thermal constraints.

2.3 Thermal Characteristics

LED performance and lifespan are critically dependent on temperature management.

• Thermal Resistance, Junction-to-Case (RθJC): This indicates how effectively heat travels from the semiconductor junction to the component's case. A lower value (e.g., 5-10 °C/W) is better, meaning heat is removed more efficiently.
• Maximum Junction Temperature (Tj max): The absolute highest temperature the LED semiconductor material can withstand without risk of catastrophic failure or accelerated degradation. This is often 125°C or 150°C.
• Operating Temperature Range: The ambient temperature range over which the device is specified to operate reliably, typically from -40°C to +85°C or +105°C.

3. Binning System Explanation

Due to manufacturing variances, LEDs are sorted into performance bins. This ensures consistency within a production batch.

3.1 Wavelength / Color Temperature Binning

LEDs are measured and grouped into tight wavelength or CCT ranges (e.g., 1nm or 2nm steps for color, 100K or 200K steps for white). This is crucial for applications requiring uniform color appearance, such as display backlights or architectural lighting.

3.2 Luminous Flux Binning

LEDs are sorted based on their light output at a standard test current. They are grouped into flux bins (e.g., a range of 5-10 lumens per bin). This allows designers to select a consistent brightness level for their product.

3.3 Forward Voltage Binning

LEDs are also binned by their forward voltage drop. Grouping LEDs with similar Vf values helps in designing more efficient driver circuits, especially when multiple LEDs are connected in series, as it minimizes current imbalance.

4. Performance Curve Analysis

Graphical data is essential for understanding component behavior under varying conditions.

4.1 Current vs. Voltage (I-V) Curve

This curve shows the relationship between the forward current and the forward voltage. It is non-linear, with a characteristic "knee" voltage. The curve shifts with temperature; at higher temperatures, the same current will result in a slightly lower forward voltage.

4.2 Temperature Characteristics

Key graphs include Luminous Flux vs. Junction Temperature and Forward Voltage vs. Junction Temperature. Light output typically decreases as temperature increases. Understanding this derating is vital for thermal design to maintain target brightness.

4.3 Spectral Power Distribution

This graph plots the relative intensity of light emitted at each wavelength. For white LEDs (typically blue chip + 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 LED's color point and CRI.

5. Mechanical and Packaging Information

Physical specifications ensure proper integration into the final product.

5.1 Dimensional Outline Drawing

A detailed mechanical drawing showing all critical dimensions: length, width, height, lens shape, and any mounting features. Tolerances are always specified.

5.2 Pad Layout and Solder Pad Design

A recommended footprint (land pattern) for the PCB is provided. This includes the size, shape, and spacing of the copper pads to ensure reliable soldering and proper thermal connection.

5.3 Polarity Identification

Clear marking of the anode (+) and cathode (-) terminals is shown, often via a diagram indicating a notch, a cut corner, a marking on the package, or different pad sizes.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

A detailed temperature vs. time graph defines the acceptable reflow process. Key parameters include preheat ramp rate, soak time and temperature, peak temperature (typically not exceeding 260°C for 10 seconds for standard packages), and cooling rate. Adhering to this profile prevents thermal shock and damage.

6.2 Precautions and Handling

• ESD Sensitivity: LEDs are often sensitive to electrostatic discharge (ESD). Proper ESD-safe handling procedures (wrist straps, conductive mats) must be followed.
• Moisture Sensitivity Level (MSL): The package is assigned an MSL rating (e.g., MSL 3) indicating how long it can be exposed to ambient humidity before it must be baked and vacuum-sealed again to prevent "popcorning" during reflow.
• Cleaning: Recommendations for post-solder cleaning agents that are compatible with the LED lens and package material.

6.3 Storage Conditions

Recommended long-term storage environment: typically in a dry, dark place at temperatures between 5°C and 30°C, with relative humidity below 60%. For MSL-rated parts, storage in a moisture-barrier bag with desiccant is required.

7. Packaging and Ordering Information

7.1 Packaging Specifications

Describes the form of delivery: tape and reel (standard for SMD components), tube, or tray. Specifies the reel size, pocket count, orientation in the tape, and leader/trailer tape.

7.2 Labeling and Marking

Explains the markings on the component package (often a simple alphanumeric code) and the labels on the reel or box, which include part number, quantity, lot number, and date code.

7.3 Model Number Nomenclature

Breaks down the part number string to explain how it encodes key attributes like color, flux bin, voltage bin, color temperature bin, and package type. This allows precise ordering.

8. Application Suggestions

8.1 Typical Application Circuits

Schematics for basic constant current driver circuits, showing how to connect the LED with a current-limiting resistor (for low current) or a dedicated LED driver IC (for higher power or precise control).

8.2 Design Considerations

• Thermal Management: Emphasizes the necessity of a properly designed PCB with adequate thermal vias and possibly a heatsink to keep the junction temperature within safe limits for performance and longevity.
• Optical Design: Considerations for secondary optics (lenses, diffusers) to achieve the desired beam pattern and light distribution.
• Electrical Design: Importance of using a constant current source, not a constant voltage source, to drive LEDs. Discusses implications of series vs. parallel connections.

9. Technical Comparison

While a direct competitor comparison is not in the source PDF, the component's features can be contextualized. A 2014-revision LED would likely offer improvements over its predecessor (Revision 1) in areas such as higher luminous efficacy, better color consistency (tighter binning), or improved thermal performance. Compared to earlier generation LEDs (pre-2010), the advantages would be even more pronounced in terms of efficiency, reliability, and cost per lumen.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Why is my LED dimmer than expected?

A: The most common cause is excessive junction temperature. Check your thermal design. Also, verify you are driving it at the correct current and that the forward voltage bin matches your driver's output voltage range.

Q: Can I drive this LED directly with a 3.3V or 5V supply?

A: Not reliably without a current-limiting mechanism. The forward voltage varies with temperature and bin. You must use a series resistor or, preferably, a constant current driver to ensure stable and safe operation.

Q: What does "Revision 2" mean for me as a designer?

A: It indicates an update to the product. You must consult the full Revision 2 datasheet, as there may be changes to electrical parameters, binning codes, or mechanical tolerances that could affect your design. Always use the latest revision.

11. Practical Use Case

Scenario: Designing a LED Panel Light for Office Illumination.

A designer selects this LED based on its efficacy and color temperature (e.g., 4000K, CRI >80). They design a metal-core PCB (MCPCB) to manage heat, placing multiple LEDs in a series-parallel configuration. They choose LEDs from the same flux and color bins to ensure uniform brightness and color across the panel. A constant-current LED driver with power factor correction (PFC) is selected to meet efficiency regulations. The reflow profile from section 6.1 is programmed into the assembly line oven. The final product meets target lumens, efficiency (lm/W), and color quality specifications for the office lighting market.

12. Principle of Operation

An LED is a semiconductor diode. When a forward voltage is applied across the p-n junction, electrons and holes recombine within the semiconductor material. This recombination process releases energy in the form of photons (light). The specific wavelength (color) of the emitted light is determined by the bandgap energy of the semiconductor material used (e.g., Gallium Nitride for blue, Aluminum Gallium Indium Phosphide for red). White LEDs are typically created by coating a blue LED chip with a yellow phosphor; some of the blue light is converted to yellow, and the mixture of blue and yellow light is perceived as white. Other methods use red, green, and blue (RGB) chips combined.

13. Development Trends

As of the document's 2014 release date, key trends in LED technology were:

Increased Efficacy: Continuous improvement in lm/W through better chip design, phosphors, and packaging.

Improved Color Quality: Development of high-CRI and tunable white LEDs for premium lighting applications.

Miniaturization: Development of smaller, more powerful packages like the 2835 (2.8mm x 3.5mm) which began replacing the older 3528 package.

Cost Reduction: Economies of scale and manufacturing improvements driving down cost per lumen, accelerating LED adoption in general lighting.

Smart Lighting: Early integration of control electronics and communication protocols (like DALI) for dimming and color tuning, paving the way for connected lighting systems.