RGB SMD LED Specification - Size 2.05x2.15x1.9mm - Voltage 1.7-3.4V - Power 0.02-0.068W - English Technical Document

1. Product Overview

This document details the specifications for a high-performance, full-color RGB (Red, Green, Blue) Surface Mount Device (SMD) LED. The device is designed with a common anode configuration and features an all-black matte surface finish to enhance contrast, making it particularly suitable for applications where high visual impact is required. Its compact footprint and robust design enable reliable operation in a variety of demanding environments.

1.1 Core Advantages

The primary advantages of this LED include its extremely wide viewing angle of 110 degrees, which ensures uniform light distribution. It offers high luminous intensity with low power dissipation, contributing to energy efficiency and long operational life. The device is rated for water resistance (IPX6), has a Moisture Sensitivity Level (MSL) of 5a, and is compliant with RoHS standards, making it suitable for modern, environmentally conscious manufacturing processes. Its design supports lead-free reflow soldering.

1.2 Target Market

This product is primarily targeted at the display and decorative lighting markets. Its key applications include outdoor full-color video screens, indoor and outdoor decorative lighting systems, amusement and entertainment products, and other general-purpose applications requiring vibrant, full-color illumination.

2. In-Depth Technical Parameter Analysis

The following sections provide a detailed, objective analysis of the device's key technical parameters as defined in the specification.

2.1 Electrical & Optical Characteristics

All measurements are specified at a standard junction temperature (Ts) of 25°C.

• Forward Voltage (V_F): The voltage drop across the LED when operating. For the Red channel at 15mA, V_F ranges from 1.7V (min) to 2.4V (max). For the Green and Blue channels, V_F ranges from 2.7V to 3.4V at their respective test currents (15mA for Green, 10mA for Blue). This variance must be accounted for in driver circuit design to ensure consistent current and color output.
• Luminous Intensity (I_V): A measure of the perceived power of light. The Red channel has an average intensity of 420 mcd, Green 740 mcd, and Blue 115 mcd. The specified Binning Range for intensity is 1:1.3 for all colors, meaning the maximum intensity in a bin will not exceed 1.3 times the minimum. This is crucial for achieving color uniformity in display arrays.
• Dominant Wavelength (λ_D): Defines the perceived color. Red: 617-628 nm (5nm binning). Green: 520-540 nm (3nm binning). Blue: 460-475 nm (3nm binning). Tighter binning (3nm) for Green and Blue indicates a greater emphasis on color purity and consistency in these channels for accurate color mixing.
• Spectral Bandwidth (Δλ): The width of the emitted spectrum at half its maximum power. Values are Red: 24 nm, Green: 38 nm, Blue: 30 nm. A narrower bandwidth generally indicates a more saturated, pure color.
• Reverse Current (I_R): Maximum leakage current of 6 μA at a reverse voltage (V_R) of 5V for all channels.
• Viewing Angle (2θ_1/2): The full angle at which luminous intensity is half of the maximum intensity. This device has a very wide 110-degree angle, ideal for applications requiring broad visibility.

2.2 Absolute Maximum Ratings

These are stress limits beyond which permanent damage may occur. Operation at or near these limits is not recommended.

• Forward Current (I_F): Red: 20 mA, Green: 15 mA, Blue: 15 mA. Exceeding these values can cause catastrophic failure due to overheating.
• Reverse Voltage (V_R): 5 V for all channels. Applying a higher reverse voltage can break down the LED junction.
• Operating Temperature (T_OPR): -30°C to +85°C. The device is rated to function within this ambient temperature range.
• Storage Temperature (T_STG): -40°C to +100°C. The device can be stored without applied power within this range.

2.3 Thermal Considerations

While not explicitly detailed with thermal resistance (R_th) values, the maximum ratings for current and temperature are the primary thermal constraints. The power dissipation for each channel can be approximated as P = V_F * I_F. At typical operating points, this results in approximately 0.036W for Red, 0.051W for Green, and 0.027W for Blue. Proper PCB thermal design, including adequate copper pads and possible thermal vias, is essential to maintain the junction temperature within safe limits, especially during continuous operation or in high ambient temperatures, to ensure longevity and stable optical performance.

3. Binning System Explanation

The specification outlines a binning system critical for production consistency.

3.1 Wavelength / Color Binning

The dominant wavelength is sorted into bins. The Red LED uses a 5nm binning step (e.g., 617-622nm, 622-627nm, etc.), while Green and Blue use a tighter 3nm binning step. This allows manufacturers to select LEDs from specific bins to achieve a desired target white point or color gamut when the RGB channels are mixed, minimizing color variation across a display or lighting fixture.

3.2 Luminous Intensity Binning

The luminous intensity is binned with a ratio of 1:1.3. This means that within a single production bin, the brightest LED will be no more than 1.3 times brighter than the dimmest LED. Using LEDs from the same intensity bin is paramount for achieving uniform brightness in an array, preventing visible "hot" or "cold" spots in a display.

3.3 Forward Voltage Binning

While not explicitly defined with bin codes, the specification provides minimum and maximum V_F values. In practice, LEDs are often further binned by forward voltage to simplify constant-current driver design and improve efficiency across a batch of devices.

4. Performance Curve Analysis

The specification references typical optical characteristic curves. While the exact graphs are not reproduced here, their general implications are analyzed.

4.1 Current vs. Voltage (I-V) Curve

The I-V curve for each color channel (Red, Green, Blue) would show the exponential relationship between forward current and forward voltage. The different turn-on voltages (lower for Red, higher for Green/Blue) are evident. Designers use this curve to select appropriate driving voltages for their constant-current circuits.

4.2 Temperature Characteristics

Typical curves would illustrate how key parameters shift with temperature. Generally, forward voltage (V_F) decreases as temperature increases. Luminous intensity also typically decreases with rising junction temperature. Understanding these relationships is vital for designing systems that maintain consistent color and brightness over the entire operating temperature range, often requiring temperature compensation in the driver circuitry.

4.3 Spectral Distribution

Spectral distribution plots show the relative power emitted at each wavelength. The dominant wavelength and spectral bandwidth values provided are derived from such plots. The shape and purity of these spectra directly influence the color rendering and mixing capabilities of the LED.

5. Mechanical & Package Information

5.1 Dimension Drawings

The device has a compact footprint measuring 2.05mm (length) x 2.15mm (width) x 1.9mm (height). All dimensional tolerances are ±0.1mm unless otherwise specified. The package features a low profile suitable for slim designs.

5.2 Pad Design & Polarity Identification

The recommended soldering pad pattern is provided to ensure proper mechanical attachment and thermal performance. The device uses a common anode configuration. Pin 1 is the common anode (+). Pins 2, 3, and 4 are the cathodes for the Red, Green, and Blue LEDs, respectively. Clear polarity marking (a dot or chamfer) is indicated on the top of the package to prevent assembly errors.

5.3 Encapsulation and Glue Filling

For applications requiring additional environmental protection or optical effects, the specification provides guidance for glue filling. It is recommended that the filling height be greater than or equal to 0.75mm to adequately cover the wire bonds and chip structures.

6. Soldering & Assembly Guidelines

6.1 SMT Reflow Soldering Parameters

The device is suitable for lead-free reflow soldering processes. While a specific reflow profile is not detailed, standard JEDEC profiles for lead-free assembly should be followed. The maximum peak temperature and time above liquidus must be controlled to prevent damage to the LED epoxy, wire bonds, or chip. The Moisture Sensitivity Level (MSL) of 5a mandates that the device must be baked before soldering if the sealed moisture barrier bag has been opened for more than 168 hours (7 days) under factory floor conditions (30°C/60%RH).

6.2 Handling and Storage Conditions

Proper storage is essential. Devices should be kept in their original moisture barrier bags with desiccant in a dry environment. The storage temperature range is -40°C to +100°C. Anti-static precautions should be observed during handling to prevent damage from electrostatic discharge (ESD), although the specification does not list a specific ESD rating.

7. Packaging & Ordering Information

7.1 Packaging Specification

The LEDs are typically supplied in carrier tape and reel packaging for automated assembly. Detailed dimensions for the carrier tape pockets and the reel are specified to ensure compatibility with standard pick-and-place equipment.

7.2 Moisture Resistant Packing

As per the MSL 5a rating, the devices are packed in moisture barrier bags with a humidity indicator card and desiccant to protect them from ambient moisture during storage and transport.

8. Application Recommendations

8.1 Typical Application Scenarios

• Outdoor Full-Color Video Screens: The high contrast black surface, wide viewing angle, and good luminous intensity make this LED well-suited for pixel pitches used in outdoor displays. The IPX6 rating provides protection against water jets.
• Indoor/Outdoor Decorative Lighting: The full-color capability allows for dynamic RGB color mixing, suitable for architectural accent lighting, signage, and mood lighting.
• Amusement & Entertainment: Ideal for integration into games, rides, and interactive installations where vibrant, reliable lighting is needed.

8.2 Design Considerations

• Driver Circuit: Use a constant-current driver for each color channel (or a combined driver with individual channel control) to ensure stable color and brightness. Account for the different forward voltages of the RGB channels.
• Thermal Management: Design the PCB with sufficient copper area for the LED pads to act as a heat sink. For high-density arrays or high ambient temperatures, consider additional thermal management strategies.
• Optical Design: The wide 110-degree viewing angle may require secondary optics (lenses, diffusers) if a more focused beam is desired. The matte black surface helps reduce unwanted reflections.
• Reverse Voltage Protection: Although the LED can tolerate up to 5V in reverse, it is good practice to include protection in the circuit (e.g., using a series diode for each channel in parallel with the LED) if there is any risk of reverse voltage being applied, such as in multiplexed driving schemes or due to wiring errors.

9. Technical Comparison & Differentiation

Compared to generic RGB LEDs, this device offers several differentiating advantages relevant to professional applications:

• High Contrast Design: The all-black matte surface significantly improves contrast ratio in display applications, especially under high ambient light conditions, resulting in darker blacks and more vivid colors.
• Defined Binning: The specification of wavelength and intensity binning (1:1.3 ratio, 3nm/5nm steps) provides a level of consistency and predictability that is essential for high-quality display manufacturing, reducing post-production calibration effort.
• Environmental Robustness: The combination of an IPX6 water resistance rating and an MSL 5a rating indicates a package designed to withstand more challenging environmental conditions during both assembly and operation than standard commercial-grade LEDs.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Why are the test currents different for the Red (15mA), Green (15mA), and Blue (10mA) channels?

A: This reflects typical operating points to achieve a target white balance or specific relative brightness levels between colors. The lower current for Blue is common because blue LEDs often have higher luminous efficacy (more light output per mA) or are driven at lower currents to balance the overall color output and system power.

Q: What does a Binning Range of 1:1.3 mean for luminous intensity?

A: It means that within a single purchased bin, the brightest LED will be no more than 30% brighter than the dimmest LED. For example, if the minimum I_V in a Red bin is 265 mcd, the maximum will be ≤ 345 mcd. This tight control is crucial for display uniformity.

Q: The device is MSL 5a. What does this mean for my assembly process?

A: Moisture Sensitivity Level 5a indicates the device can be exposed to factory floor conditions (≤ 30°C / 60% RH) for up to 168 hours (7 days) after the bag is opened. If not soldered within this time, it must be baked according to the specified conditions (e.g., 125°C for 24 hours) to remove absorbed moisture before reflow soldering to prevent "popcorn" cracking.

Q: Can I drive the Red LED at 20mA continuously?

A: The Absolute Maximum Rating for Red I_F is 20mA. Continuous operation at this maximum rating is not advised as it stresses the device and will likely reduce its lifespan. For reliable long-term operation, it is standard practice to derate the current, often operating at 50-75% of the maximum rating (e.g., 10-15mA for Red). Always refer to the recommended operating conditions in the design.

11. Practical Use Case Example

Scenario: Designing a Fine-Pitch Indoor LED Video Wall Module.

A designer is creating a P2.5 (2.5mm pixel pitch) indoor display module. They select this RGB LED for its compact 2.05x2.15mm size, which fits the pixel layout. To ensure color uniformity, they work with the supplier to specify tight bins for dominant wavelength (e.g., Red: 622-627nm, Green: 528-531nm, Blue: 466-469nm) and request LEDs from a single luminous intensity bin. The PCB layout follows the recommended soldering pad pattern to ensure good solder joint formation and thermal conduction. A constant-current driver IC with PWM dimming for each color channel is selected. The wide 110-degree viewing angle ensures good visibility for audiences standing at various angles to the screen. The matte black surface of the LED helps improve the module's contrast ratio in the brightly lit indoor environment.

12. Operating Principle Introduction

This is a semiconductor light-emitting device. Each color (Red, Green, Blue) is produced by a separate semiconductor chip made from different material systems (e.g., AlInGaP for Red, InGaN for Green and Blue). When a forward voltage exceeding the chip's bandgap energy is applied, electrons and holes recombine within the semiconductor material, releasing energy in the form of photons (light). The wavelength (color) of the emitted light is determined by the bandgap energy of the semiconductor material. The common anode configuration means all three chips share a single positive electrical connection, simplifying the external drive circuitry to three cathode connections (one for each color).

13. Technology Trends

The market for full-color SMD LEDs continues to evolve. General trends observable in devices like this one include:

• Increased Efficiency: Ongoing improvements in epitaxial growth and chip design lead to higher luminous efficacy (more lumens per watt), allowing for brighter displays or lower power consumption.
• Miniaturization: The drive for finer pixel pitches in displays pushes package sizes smaller while maintaining or improving optical output.
• Enhanced Reliability: Improvements in packaging materials, wire bonding, and encapsulation techniques lead to longer lifetimes and better performance in harsh environments (higher temperature, humidity).
• Tighter Binning & Consistency: As display quality demands increase, the need for tighter control over color and brightness parameters becomes more critical, leading to more sophisticated binning systems and production controls.
• Integrated Solutions: A trend towards combining the LED with driver ICs or control logic into more integrated packages to simplify system design and improve performance.