White LED Specification - 3.0x3.0x0.55mm EMC Package - 3.1V - ~1.1W - English Technical Document

1. Product Overview

This document details the specifications for a high-brightness white light-emitting diode (LED) designed for demanding applications. The product utilizes a blue LED chip combined with phosphor to produce white light, encapsulated in a robust Epoxy Molding Compound (EMC) package. With dimensions of 3.0mm x 3.0mm x 0.55mm, it represents a compact yet powerful lighting solution.

Core Advantages: The primary advantages of this LED include its exceptional reliability afforded by the EMC material, which offers superior resistance to heat and UV degradation compared to traditional plastics. It features an extremely wide 120-degree viewing angle, making it suitable for applications requiring broad illumination. Furthermore, it is fully qualified for automotive use according to the stringent AEC-Q102 stress test guidelines.

Target Market: The primary target application is automotive lighting, encompassing both interior and exterior functions. This includes, but is not limited to, interior ambient lighting, dashboard indicators, and various exterior signal lights where high reliability and performance are non-negotiable.

2. In-Depth Technical Parameter Analysis

The electrical and optical characteristics are defined at a standard junction temperature (Ts) of 25°C. It is crucial to understand that these parameters can vary with operating temperature.

2.1 Electro-Optical Characteristics

The typical forward voltage (VF) is 3.1V when driven at the standard test current of 350mA, with a range from 2.8V to 3.4V. At this current, the luminous flux output has a typical value of 125 lumens (lm), with a minimum of 105 lm and a maximum of 144 lm. The device exhibits a very wide viewing angle (2θ1/2) of 120 degrees, providing diffuse, wide-area illumination.

2.2 Absolute Maximum Ratings and Limits

Adherence to absolute maximum ratings is critical for device longevity. The maximum continuous forward current (IF) is 420 mA. A higher peak forward current (IFP) of 700 mA is permissible but only under pulsed conditions (1/10 duty cycle, 10ms pulse width). The maximum power dissipation (PD) is 1428 mW. The device can withstand a reverse voltage (VR) of up to 5V and has an ESD tolerance (Human Body Model) of 8000V. The operating and storage temperature range is -40°C to +125°C, with a maximum junction temperature (Tj) of 150°C.

2.3 Thermal Characteristics

The thermal resistance from the junction to the solder point (RthJ-S) is specified as a maximum of 14 °C/W. This parameter is vital for thermal management design. A lower thermal resistance indicates more efficient heat transfer from the LED chip to the circuit board, helping to maintain lower junction temperatures for improved performance and lifespan. Exceeding the maximum junction temperature is a primary cause of LED failure.

3. Binning System Explanation

To ensure consistency in production, LEDs are sorted into bins based on key parameters. This allows designers to select parts that meet specific requirements for their application.

3.1 Forward Voltage Binning

The forward voltage is categorized into six bins: G1 (2.8-2.9V), G2 (2.9-3.0V), H1 (3.0-3.1V), H2 (3.1-3.2V), I1 (3.2-3.3V), and I2 (3.3-3.4V). This information is essential for designing driver circuits and predicting power consumption.

3.2 Luminous Flux Binning

The luminous flux output at 350mA is sorted into three bins: SA (105-117 lm), SB (117-130 lm), and TA (130-144 lm). Selection depends on the required brightness level for the application.

3.3 Chromaticity Binning

The color of the white light is defined by its coordinates on the CIE chromaticity diagram. The provided chart and table (e.g., VM1, VM2, VM3) define specific quadrilateral regions on this diagram. LEDs are binned based on which region their color coordinates fall into, ensuring color consistency within a batch.

4. Performance Curve Analysis

While specific graphical curves are referenced in the document (Typical Optical Characteristics Curves), their implications are critical. Typically, such curves would illustrate the relationship between forward current and voltage (IV curve), forward current and luminous flux, and the effect of junction temperature on light output. Understanding these curves allows designers to optimize drive conditions. For instance, driving the LED above the typical current increases light output but also increases heat and can accelerate lumen depreciation. The dependence of light output on temperature underscores the importance of effective heat sinking.

5. Mechanical and Package Information

The package is a surface-mount device (SMD) with precise dimensions critical for PCB layout.

5.1 Dimensioned Drawings

The specification includes top, side, and bottom views. Key dimensions are: 3.00mm length, 3.00mm width, and 0.55mm height. The bottom view shows the anode and cathode pad layout, which is asymmetrical to aid in correct orientation.

5.2 Polarity Identification

Polarity is clearly marked. The cathode side is typically indicated by a marking or a chamfered corner on the top of the package. Correct polarity must be observed during assembly to prevent damage.

5.3 Recommended Solder Pad Pattern

A land pattern design is provided to ensure reliable soldering and optimal thermal performance. The recommended pattern includes pads for the electrical contacts, with specific dimensions (e.g., 2.40mm x 1.55mm for the main pad) to facilitate good solder fillets and mechanical stability.

6. Soldering and Assembly Guidelines

6.1 SMT Reflow Soldering Instructions

The product is suitable for all standard SMT assembly processes. It is supplied on tape and reel for compatibility with automated pick-and-place equipment. The moisture sensitivity level (MSL) is rated as Level 2. This means the devices can be exposed to factory floor conditions (≤ 30°C/60% RH) for up to one year before they require baking. If exceeded, baking is necessary prior to reflow to prevent popcorn cracking during soldering.

6.2 Handling and Storage Precautions

Despite a high ESD rating (8000V HBM), standard ESD precautions should be followed during handling. The maximum operating current must be determined based on the actual thermal conditions of the application to ensure the junction temperature does not exceed 150°C. Power dissipation must not exceed the absolute maximum rating.

7. Packaging and Ordering Information

The LEDs are packaged in embossed carrier tape on reels for automated assembly. Detailed dimensions for the carrier tape pockets and the reel itself are provided to ensure compatibility with manufacturing equipment. The packaging includes moisture barrier bags with desiccant for MSL Level 2 compliance. Labels on the reel and box contain critical information such as part number, quantity, lot number, and bin codes.

8. Application Recommendations

Typical Application Scenarios: This LED is explicitly designed for automotive lighting. This makes it ideal for interior applications like footwell lighting, dashboard backlighting, and switch illumination. For exterior use, it can be employed in daytime running lights (DRLs), side marker lights, center high-mount stop lights (CHMSL), and other signal functions where its reliability and brightness are assets.

Design Considerations: The wide 120-degree viewing angle eliminates the need for secondary optics in many diffuse lighting applications, simplifying design. However, for focused beams, a primary optic (lens) will be required. Thermal management is the foremost design priority. The PCB should use thermal vias and, if necessary, a metal-core board to effectively transfer heat away from the LED solder pads. The driver circuit should be designed to account for the forward voltage binning range and include appropriate current regulation or limiting.

9. Technical Comparison and Differentiation

The key differentiating factor of this product is its EMC (Epoxy Molding Compound) package. Compared to LEDs in standard PPA (Polyphthalamide) or other plastic packages, EMC offers significantly better thermal performance, higher temperature resistance, and superior resistance to yellowing from UV exposure and thermal aging. This directly translates to longer lifespan and more stable light output over time, which is paramount in automotive applications where product lifetimes of 10-15 years are expected. The AEC-Q102 qualification provides a standardized assurance of reliability under automotive stress conditions, which is not universally offered by commercial-grade LEDs.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED at 700mA continuously?

A: No. The absolute maximum continuous current is 420 mA. The 700mA rating is for pulsed operation only under specific conditions (10ms pulse, 1/10 duty cycle). Continuous operation at 700mA would exceed the maximum power dissipation and junction temperature, leading to rapid failure.

Q: What does a thermal resistance of 14 °C/W mean?

A: It means that for every watt of power dissipated in the LED chip, the temperature difference between the chip (junction) and the solder point will increase by 14°C. For example, at 3.1V and 350mA (≈1.085W), the temperature rise from the board to the junction would be approximately 15.2°C (1.085W * 14°C/W).

Q: How do I select the right voltage bin (G1, H1, etc.)?

A: Your selection depends on your driver design. If using a constant-voltage source with a current-limiting resistor, a tighter voltage bin (e.g., just H1) will result in more consistent current and brightness across all LEDs. For constant-current drivers, the voltage bin is less critical for performance but may affect power consumption slightly.

11. Real-World Design Case

Consider designing an automotive interior map light. The requirement is for soft, diffuse white illumination. The wide 120-degree viewing angle of this LED makes it an excellent choice, as it can illuminate a wide area without hotspots, potentially eliminating the need for a diffuser lens. A designer would select a luminous flux bin (e.g., SB for medium brightness) and likely a specific chromaticity bin (e.g., VM2) for a desired white color tone. The LED would be driven by a simple constant-current driver circuit set to 350mA. The PCB layout would incorporate the recommended solder pad pattern with thermal vias connecting to a larger copper pour to act as a heat spreader, ensuring the junction temperature remains well below 125°C during operation.

12. Operating Principle

The white light is generated using a phosphor-conversion method. The core of the device is a semiconductor chip that emits blue light when electrical current passes through it. This blue chip is coated with a layer of yellow (or a mix of green and red) phosphor. A portion of the blue light from the chip is absorbed by the phosphor, which then re-emits it as light of longer wavelengths (yellow). The combination of the remaining unabsorbed blue light and the emitted yellow light is perceived by the human eye as white light. The specific ratio of blue to yellow and the types of phosphors used determine the correlated color temperature (CCT) of the white light (e.g., cool white, neutral white, warm white).

13. Industry Trends and Developments

The trend in automotive LED lighting is towards higher power density, greater efficiency (lumens per watt), and increased integration. Packages are becoming smaller while delivering more light, enabling sleeker and more compact lamp designs. There is a strong focus on improving reliability and longevity to meet automotive standards, which drives the adoption of robust packaging materials like EMC and ceramics. Furthermore, advanced features like adaptive driving beam (ADB) headlights and dynamic signal lights are pushing the integration of control electronics closer to or directly with the LED package itself. The demand for precise and consistent color rendering is also increasing, especially for interior ambient lighting where specific mood lighting effects are desired.