White LED PLCC-2 Specification - Size 2.8x3.5x0.7mm - Voltage 3.15V - Power 0.594W - English Technical Document

1. Product Overview

This document provides a comprehensive technical specification for a high-performance white light-emitting diode (LED) designed for general illumination applications. The device utilizes a blue LED chip combined with a phosphor coating to produce white light, a common and efficient method in solid-state lighting technology. The product is housed in a PLCC-2 (Plastic Leaded Chip Carrier) surface-mount package, which is widely adopted in the industry for its reliability and compatibility with automated assembly processes. The LED is characterized by its broad viewing angle and consistent optical performance, making it suitable for a variety of indoor lighting solutions where uniform light distribution is required.

1.1 Features

• PLCC-2 package design for robust mechanical structure and good thermal management.
• Extremely wide viewing angle, typically 120 degrees, ensuring broad illumination coverage.
• Fully compatible with standard SMT (Surface Mount Technology) assembly and solder reflow processes, facilitating high-volume manufacturing.
• Available packaged on tape and reel for automated pick-and-place equipment.
• Moisture sensitivity level is classified as Level 3, indicating specific handling and storage requirements to prevent moisture-induced damage during reflow.
• Compliant with RoHS (Restriction of Hazardous Substances) directives, ensuring the product is free from specified hazardous materials.

1.2 Application

The primary application areas for this LED include indoor general lighting, retrofit bulb lighting, and various other indoor illumination scenarios. Its parameters are optimized for tasks requiring good color rendering and efficient light output, such as in residential lighting, commercial downlights, and decorative lighting fixtures. The combination of its form factor and performance makes it a versatile component for lighting designers and engineers.

2. Detailed Technical Parameters and Analysis

The following sections delve into the critical electrical, optical, and thermal parameters that define the LED\'s performance. Understanding these parameters is essential for proper circuit design and system integration to ensure longevity and optimal light output.

2.1 Electrical and Optical Characteristics

All measurements are specified at a solder point temperature (Ts) of 25°C. The key parameters are summarized below, with a detailed analysis of each.

• Forward Voltage (VF): At a test current (IF) of 150mA, the forward voltage has a minimum of 3.0V, a typical value of 3.15V, and a maximum of 3.3V. This parameter is crucial for driver design; a constant current source is recommended to ensure stable light output and prevent thermal runaway, as the forward voltage has a negative temperature coefficient.
• Reverse Current (IR): With a reverse voltage (VR) of 5V applied, the maximum reverse current is 10µA. This indicates the quality of the LED chip's p-n junction and its ability to withstand small reverse biases that may occur in circuit transients.
• Luminous Flux (Φ): The total light output, measured in lumens (lm), varies depending on the correlated color temperature (CCT) bin of the specific product variant. For example, for a warm white variant (CCT range 2580-2880K), the luminous flux is typically 58lm at 150mA. Cooler white variants (e.g., 5320-6090K) offer a typical flux of 66lm. This binning allows designers to select the appropriate brightness for their color temperature requirement.
• Viewing Angle (2θ_1/2): The full viewing angle at half intensity is typically 120 degrees. This wide angle is ideal for applications requiring diffuse, non-directional light, reducing the need for secondary optics in many general lighting fixtures.
• Color Rendering Index (CRI): The CRI is specified with a minimum of 80 and typical of 82. This metric indicates how accurately the LED light renders colors compared to a natural light source. A CRI above 80 is considered good for general indoor lighting, making this LED suitable for environments where color perception is important.
• Thermal Resistance (R_THJ-S)): The junction-to-solder point thermal resistance has a maximum value of 30°C/W. This is a critical parameter for thermal management. The lower this value, the more efficiently heat is conducted away from the LED junction. Proper PCB design with adequate thermal vias and copper area is necessary to maintain a low junction temperature, which directly impacts LED lifetime and luminous maintenance.
• Electrostatic Discharge (ESD) Protection: The device can withstand a Human Body Model (HBM) ESD pulse of up to 2000V. This level of protection is standard for most LEDs and helps prevent damage during handling and assembly, but standard ESD precautions should still be observed.

2.2 Absolute Maximum Ratings

Operating the device beyond these limits may cause permanent damage. The ratings are defined at an ambient temperature of 25°C.

• Power Dissipation (P_D)): 594mW. This is the maximum allowable power that can be dissipated as heat. Exceeding this limit risks overheating the junction.
• Forward Current (I_F)): 180mA continuous. This is the maximum DC current recommended for reliable long-term operation.
• Peak Forward Current (I_FP)): 240mA, but only under pulsed conditions (1/10 duty cycle, 10ms pulse width). This allows for brief overdrive in applications like dimming or sensing.
• Reverse Voltage (V_R)): 5V. Applying a higher reverse voltage can break down the junction.
• Operating and Storage Temperature: -40°C to +100°C. This wide range ensures reliability in various environmental conditions.
• Junction Temperature (T_J)): 125°C maximum. The actual junction temperature during operation must be calculated based on thermal resistance and power dissipation to ensure it stays below this limit for long-term reliability.

2.3 Bin Range System for Forward Voltage and Luminous Flux

To ensure consistency in mass production, LEDs are sorted into bins based on key parameters. This allows designers to select parts that meet specific system requirements for voltage drop and brightness.

• Forward Voltage Binning: At IF=150mA, the forward voltage is categorized into three bins: H1 (3.0-3.1V), H2 (3.1-3.2V), and I1 (3.2-3.3V). This helps in matching LEDs in series strings to prevent current imbalance.
• Luminous Flux Binning: The luminous flux is binned into four categories: SHA (55-60 lm), TEA (60-65 lm), TFA (65-70 lm), and TGA (70-75 lm). These bins are typically linked to the color temperature variant, as shown in the product parameters table.
• Color Coordinate Binning: The document includes a CIE chromaticity diagram with defined quadrilateral regions (e.g., A27, A30, A35 up to 65K) specifying the acceptable color coordinates (x, y) for each white point bin. This precise binning ensures tight color consistency within a batch of LEDs, which is critical for applications where multiple LEDs are used together and color mixing must be uniform.

2.4 Performance Curve Analysis

While the PDF references typical optical characteristics curves, the specific graphs for current vs. luminous flux (L-I curve), forward voltage vs. temperature, and spectral power distribution are not provided in the text. However, based on the parameters given, one can infer general performance trends. The luminous flux is approximately linear with current in the recommended operating range. The forward voltage will decrease as the junction temperature rises. The spectral output will depend on the phosphor blend used for the specific CCT bin, with warmer whites having more energy in the red part of the spectrum and cooler whites having more blue/green content. Designers should consult the manufacturer's full datasheet for graphical data to model system performance accurately.

3. Mechanical and Package Information

The physical dimensions and layout are critical for PCB footprint design and ensuring proper solder joint formation.

3.1 Package Dimensions and Drawings

The LED package has a body size of approximately 2.80mm in length, 3.50mm in width, and 0.70mm in height (excluding leads). All dimension tolerances are ±0.05mm unless otherwise noted. The package includes two leads for electrical connection.

3.2 Polarity Identification and Soldering Pattern

The anode (A, positive) and cathode (C, negative) are clearly marked. The recommended solder pad pattern on the PCB is provided to ensure a reliable mechanical and electrical connection while allowing for proper thermal relief. The pad design helps in achieving a good solder fillet during the reflow process.

4. Packaging, Handling, and Reliability

4.1 Packaging Specification

The LEDs are supplied on embossed carrier tape wound onto reels, suitable for automated SMT assembly. Detailed dimensions for the carrier tape pockets and the reel are specified to ensure compatibility with standard feeder systems. A label on the reel provides traceability information such as part number, quantity, and lot code.

4.2 Moisture Sensitivity and Storage

As a Level 3 moisture-sensitive device, the product must be stored in a dry environment (typically below 30°C/60% RH) in its original moisture barrier bag. Once the bag is opened, the components should be used within 168 hours (7 days) under factory floor conditions or be re-baked according to standard IPC/JEDEC guidelines before reflow soldering to prevent \"popcorn\" damage.

4.3 Reliability Test Overview

The product is subjected to a series of reliability tests to ensure performance under various stress conditions. Common tests include high-temperature storage, low-temperature storage, temperature cycling, humidity testing, and solder heat resistance. Specific conditions and pass/fail criteria (e.g., limits for changes in forward voltage or luminous intensity) are defined to guarantee a long operational lifetime, typically exceeding 50,000 hours under proper operating conditions.

5. SMT Reflow Soldering Instructions

To achieve reliable solder joints without damaging the LED, a controlled reflow profile must be used.

• Profile Type: A standard convection reflow profile is recommended.
• Peak Temperature: The maximum body temperature during reflow must not exceed the rated temperature (implied by the moisture sensitivity and package material limits, typically around 260°C for a few seconds).
• Preheat and Soak: A gradual preheat zone is necessary to activate the flux and slowly bring the entire assembly to a uniform temperature, minimizing thermal shock.
• Time Above Liquidous (TAL): The time the solder paste is in a molten state should be controlled to ensure good wetting without excessive intermetallic growth or component stress.
• It is critical to follow the specific profile recommendations, including ramp-up and cool-down rates, to prevent cracking of the plastic package or detachment of the silicone lens due to thermal expansion mismatches.

6. Application Guidelines and Design Considerations

6.1 Typical Application Scenarios

Beyond basic indoor lighting, this LED can be used in LED tubes, panel lights, candle bulbs, and other luminaires where a PLCC-2 form factor is standard. Its wide beam angle reduces the need for complex diffusers in many retrofit applications.

6.2 Driver Circuit Design

A constant current LED driver is essential. The driver output current should be set at or below the recommended 150mA for normal operation, considering the forward voltage bin to calculate the necessary driver voltage compliance. Thermal design on the PCB is paramount; using a board with a thermal pad connected through vias to an internal ground plane can significantly lower the thermal resistance from the LED solder point to the ambient.

6.3 Optical Design Considerations

For applications requiring specific beam patterns, secondary optics such as lenses or reflectors can be mounted above the LED. The wide inherent viewing angle provides a good starting point for optic design. The CRI and CCT bin should be selected based on the desired lighting ambiance and color accuracy requirements of the end application.

7. Technical Analysis, FAQs, and Trends

7.1 Operating Principle of White LEDs

This LED generates white light through a process called phosphor conversion. A semiconductor chip emitting blue light (typically based on InGaN) is coated with a yellow-emitting phosphor material (often YAG:Ce). Part of the blue light is absorbed by the phosphor and re-emitted as yellow light. The mixture of the remaining blue light and the converted yellow light appears white to the human eye. By adjusting the phosphor composition and concentration, different correlated color temperatures (CCT) from warm white to cool white can be achieved.

7.2 Frequently Asked Questions (FAQs)

• Q: What is the main cause of LED lifetime degradation? A: The primary factors are high junction temperature and drive current. Operating the LED within its specified temperature and current limits is crucial for long-term luminous maintenance and color stability.
• Q: Can multiple LEDs of different voltage bins be used in the same series string? A: It is not recommended. Differences in forward voltage will cause current imbalance, leading to uneven brightness and potentially overstressing LEDs with lower voltage. Use LEDs from the same or adjacent voltage bins for series connections.
• Q: How does ambient temperature affect light output? A: As the ambient (and thus junction) temperature increases, the luminous flux typically decreases. This thermal derating must be accounted for in the system's thermal design to ensure the desired light level is maintained in the operating environment.
• Q: Is a heatsink required for this LED? A: For low-power applications or when only a few LEDs are used on a well-designed PCB, an external heatsink might not be necessary. However, for arrays or high-power applications, proper thermal management via the PCB and/or an attached heatsink is essential to keep the junction temperature low.

7.3 Industry Trends and Comparison

The PLCC-2 package remains a cost-effective and reliable workhorse for mid-power LED applications. Compared to newer package types like COB (Chip-on-Board) or high-density mid-power packages, PLCC-2 offers a good balance of ease of use, proven reliability, and compatibility with existing manufacturing infrastructure. The trend in the industry is towards higher efficacy (more lumens per watt), better color uniformity, and higher CRI values. This particular LED, with its CRI >80 and multiple CCT options, aligns with the market demand for quality illumination in energy-efficient general lighting. Its compatibility with standard SMT processes gives it an advantage in terms of lower total assembly cost compared to packages requiring special handling.

7.4 Practical Design Case Study

Consider designing a simple LED downlight module using 12 of these LEDs. The designer would select a specific CCT bin (e.g., A40 for 4000K neutral white) and a luminous flux bin (e.g., TEA for 60-65lm). Wiring them in a 4-series-by-3-parallel configuration requires a driver with an output current of 450mA (3*150mA) and a voltage range covering 4 * (VF of the series string, considering the worst-case max VF). The PCB must be designed with sufficient copper area and thermal vias under each LED's solder pads to conduct heat to a metal core or a larger copper layer. By calculating the expected power dissipation (12 * 3.15V * 0.15A ≈ 5.67W) and the thermal resistance path, the designer can verify that the junction temperature remains well below 125°C, ensuring a long product life.