5515-RGB020AH-AM SMD RGB LED Datasheet - 5.5x1.5mm - Red/Green/Blue - 20mA - Automotive Grade

1. Product Overview

The 5515-RGB020AH-AM is a high-performance, surface-mount (SMD) LED component integrating red, green, and blue (RGB) emitters within a single 5.5mm x 1.5mm package. It is specifically engineered and qualified for demanding automotive electronic environments. Its core advantages include high luminous output, a wide 120-degree viewing angle, and robust construction meeting stringent automotive reliability standards such as AEC-Q102. The primary target market is automotive interior lighting systems, including ambient lighting, switch backlighting, and other decorative or functional illumination applications where color mixing and reliability are critical.

2. In-Depth Technical Parameter Analysis

2.1 Photometric & Optical Characteristics

The LED's performance is characterized at a standard test current of 20mA and a thermal pad temperature of 25°C. The typical luminous intensity values are 1120 millicandelas (mcd) for the red chip, 2800 mcd for the green chip, and 450 mcd for the blue chip. These values represent the peak brightness achievable under standard conditions. The dominant wavelengths, which define the perceived color, are typically 621nm for red, 527nm for green, and 467nm for blue. All three colors share a consistent, wide viewing angle (2φ) of 120 degrees, ensuring uniform light distribution. Measurement tolerances are ±8% for luminous intensity and ±1nm for dominant wavelength.

2.2 Electrical & Thermal Parameters

The forward voltage (V_F) at 20mA is typically 2.00V for red, 2.75V for green, and 3.00V for blue. The maximum continuous forward current (I_F) ratings differ: 50mA for red and 30mA for both green and blue. This difference is primarily due to the varying efficiency and thermal characteristics of the different semiconductor materials. The absolute maximum power dissipation ratings are 137.5mW (Red), 105mW (Green), and 112.5mW (Blue). Thermal management is crucial; the junction-to-solder point thermal resistance (R_thJS) is specified with both real (measured) and electrical (calculated) values. For instance, the real thermal resistance is up to 52 K/W for red and 85 K/W for green/blue, indicating the need for adequate PCB thermal design to maintain performance and longevity.

2.3 Absolute Maximum Ratings and Reliability

The device is rated for an operating temperature range of -40°C to +110°C, suitable for the harsh environment inside a vehicle. The maximum allowable junction temperature is 125°C. It features Electrostatic Discharge (ESD) protection rated at 2kV (Human Body Model), which is essential for handling during manufacturing. The product is compliant with RoHS, REACH, and halogen-free regulations (Br/Cl < 900ppm, Br+Cl < 1500ppm). It also meets Corrosion Robustness Class B1, indicating a degree of resistance to corrosive atmospheres, and has a Moisture Sensitivity Level (MSL) of 3.

3. Performance Curve Analysis

The datasheet provides several key graphs that are vital for circuit design and performance prediction.

3.1 Forward Current vs. Forward Voltage (I-V Curve)

The I-V curve shows the relationship between the current flowing through the LED and the voltage across it. Each color has a distinct curve due to different semiconductor bandgaps. The red LED has the lowest forward voltage, followed by green, then blue. Designers use this graph to select appropriate current-limiting resistors or constant-current driver settings to ensure the LED operates within its specified voltage range for a desired current.

3.2 Relative Luminous Intensity vs. Forward Current

This graph illustrates how light output changes with drive current. Typically, luminous intensity increases with current but not always linearly, especially at higher currents where efficiency may drop due to heating. This information is critical for designing dimming circuits or achieving specific brightness levels.

3.3 Temperature Dependency Graphs

Three key graphs show performance variation with junction temperature (T_j):
1. Relative Luminous Intensity vs. Junction Temperature: Light output generally decreases as temperature increases. The rate of decrease varies by color, affecting color balance in RGB applications if temperatures are not controlled.
2. Relative Forward Voltage vs. Junction Temperature: Forward voltage typically decreases with increasing temperature. This characteristic can be used for temperature sensing but must be considered in constant-voltage drive schemes.
3. Dominant Wavelength Shift vs. Junction Temperature: The emitted color wavelength shifts slightly with temperature. While the shift is usually small (a few nanometers over the operating range), it can be important for color-critical applications.

3.4 Forward Current Derating Curves

Separate curves for red and for green/blue show the maximum allowable continuous forward current as a function of the solder pad temperature (T_S). As the PCB temperature rises, the maximum safe current decreases to prevent the junction temperature from exceeding 125°C. For example, the red LED's maximum current derates from 50mA at 103°C solder point temperature to 35mA at 110°C. These curves are essential for ensuring reliable operation in real-world applications with varying ambient temperatures.

3.5 Spectral Distribution and Radiation Pattern

The relative spectral distribution graph shows the intensity of light emitted across the wavelength spectrum for each color. It confirms the narrowband nature of the LEDs, with peaks at their respective dominant wavelengths. The typical radiation diagram (not fully detailed in the excerpt) would visually represent the 120-degree viewing angle, showing how intensity falls off at angles away from the center (perpendicular to the LED surface).

4. Binning Information

The datasheet includes a dedicated section for binning information. In LED manufacturing, "binning" is the process of sorting LEDs based on measured parameters like luminous intensity (brightness), forward voltage (V_F), and dominant wavelength (color). This is necessary due to inherent minor variations in the semiconductor production process. The binning tables (referenced in the contents) define the specific ranges or codes for each parameter bin. For designers, understanding the binning is crucial for ensuring color consistency and electrical performance matching when using multiple LEDs in a single assembly, such as in an ambient light strip. The typical values listed in the characteristics table represent the center of the expected distribution, but actual purchased parts will fall into specific bins as per the ordering code.

5. Mechanical & Packaging Information

5.1 Mechanical Dimensions

The component uses a 5515 package footprint, which denotes a body size of approximately 5.5mm in length and 1.5mm in width. The detailed mechanical drawing (Section 7) specifies all critical dimensions including overall height, lead spacing, pad sizes, and tolerances. This drawing is essential for PCB layout designers to create the correct footprint in their CAD software.

5.2 Recommended Solder Pad Layout & Polarity

Section 8 provides a recommended land pattern (solder pad design) for the PCB. Using the recommended pad geometry ensures proper solder joint formation during reflow, good mechanical strength, and optimal thermal transfer from the LED's thermal pad to the PCB. The diagram also clearly indicates the polarity or pin-1 marking, which is critical for correct electrical connection of the red, green, and blue anodes and the common cathode (assuming a common-cathode configuration, which is typical for RGB LEDs).

5.3 Packaging Information

The LEDs are supplied on tape and reel for automated pick-and-place assembly. Section 10 details the packaging specifications, including reel dimensions, tape width, pocket spacing, and orientation. This information is necessary for programming the assembly equipment correctly.

6. Soldering & Assembly Guidelines

6.1 Reflow Soldering Profile

Section 9 specifies the recommended reflow soldering profile. This is a time-temperature graph that defines how the PCB assembly should be heated to melt the solder paste and form reliable connections without damaging the LED. Key parameters include preheat slope, soak time and temperature, peak temperature (not to exceed 260°C for 30 seconds, as per the absolute maximum ratings), and cooling rate. Adhering to this profile is vital for yield and long-term reliability.

6.2 Precautions for Use

Section 11 lists important handling and usage precautions. These likely include warnings about:
- Avoiding mechanical stress on the LED lens.
- Protecting the device from excessive electrostatic discharge (ESD) during handling, despite its 2kV rating.
- Ensuring the PCB and assembly process are clean to prevent contamination.
- Following the current derating guidelines based on operating temperature.
- Using appropriate current-limiting methods (resistors or drivers) to prevent over-current.

6.3 Sulfur Resistance Test Criteria

Section 12 mentions sulfur test criteria. Certain environments, especially some automotive interiors or industrial settings, may contain sulfurous gases that can corrode silver-based LED components. This test verifies the LED's robustness against such corrosive atmospheres, which is part of its automotive-grade qualification.

7. Application Suggestions & Design Considerations

7.1 Typical Application Scenarios

Primary Application: Automotive interior ambient lighting for door panels, footwells, dashboard accents, and center consoles.
Secondary Applications: Backlighting for buttons, switches, and control panels; decorative lighting in consumer electronics where automotive-grade reliability is desired.

7.2 Critical Design Considerations

1. Drive Circuitry: Use constant-current drivers for optimal color consistency and brightness control, especially for PWM dimming. If using simple resistor current limiting, calculate resistors separately for each color channel due to their different forward voltages.
2. Thermal Management: The thermal resistance values necessitate a PCB design with adequate thermal relief. Use thermal vias under the LED's thermal pad connected to a ground plane or a dedicated copper pour to dissipate heat.
3. Color Mixing & Control: To achieve a wide gamut of colors (including white), independent pulse-width modulation (PWM) control of each color channel is highly recommended. The different luminous intensities (Red: 1120mcd, Green: 2800mcd, Blue: 450mcd) mean the drive current or PWM duty cycle for each channel must be calibrated to achieve a desired white point or color balance.
4. Optical Design: The 120° viewing angle is suitable for diffuse, wide-area illumination. For more focused light, secondary optics (lenses or light guides) would be required. The side-view form factor is designed to emit light parallel to the PCB surface, ideal for edge-lighting light guides.

8. Technical Comparison & Differentiation

While the PDF does not compare directly to other parts, key differentiators of this component can be inferred:
- Automotive Qualification (AEC-Q102): This is a significant differentiator from commercial-grade LEDs, involving rigorous testing for temperature cycling, humidity, high-temperature operation, and other stressors specific to automotive environments.
- High Luminous Intensity: The green and red outputs are particularly high for a 20mA drive current, potentially reducing the number of LEDs needed for a given brightness level.
- Integrated RGB in Side-View Package: Combines three colors in a compact, low-profile package suitable for space-constrained backlighting applications, eliminating the need to place three separate LEDs.
- Corrosion & Sulfur Resistance: Meets specific standards for harsh environments, which many standard LEDs do not.

9. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED with a 5V supply?
A: Yes, but you must use current-limiting resistors. For example, for the blue LED (V_F typ. 3.0V @20mA), the resistor value would be R = (5V - 3.0V) / 0.020A = 100 Ohms. Always use the maximum V_F from the datasheet for a robust design.

Q: Why are the maximum currents different for red vs. green/blue?
A: This is due to differences in semiconductor material efficiency and thermal characteristics. The red chip (likely AlInGaP) can typically handle higher current densities than the green/blue chips (likely InGaN) within the same package thermal constraints.

Q: How do I create white light with this RGB LED?
A: White light is created by mixing the three primary colors. Due to the different luminous intensities, you cannot simply drive all three at the same current. You must adjust the relative intensity of each channel (via different resistor values or PWM duty cycles) to mix to a specific white point (e.g., D65). This requires calibration.

Q: What is the meaning of MSL 3?
A: Moisture Sensitivity Level 3 means the packaged LEDs can be exposed to factory floor conditions (≤30°C/60% RH) for up to 168 hours (7 days) before they must be soldered. If exceeded, they require baking to remove absorbed moisture that could cause "popcorning" (package cracking) during reflow soldering.

10. Practical Design Case Study

Scenario: Designing an automotive door panel ambient light strip using ten 5515-RGB020AH-AM LEDs.
Steps:
1. PCB Layout: Place LEDs with recommended pad layout. Connect the thermal pad to a large copper area with multiple thermal vias to an internal ground plane for heat sinking. Ensure traces for the three anodes and common cathode are adequately sized.
2. Drive Circuit: Select a 3-channel constant-current LED driver IC designed for automotive use. Set the driver's current limit to 20mA per channel per LED. Since ten LEDs are in parallel on each channel, the driver must supply 200mA per color channel. Alternatively, wire LEDs in series for better current matching, but this requires a higher supply voltage.
3. Thermal Analysis: Calculate worst-case power dissipation: (10 LEDs * (2.0V*0.02A for Red)) + (10*(2.75V*0.02A for Green)) + (10*(3.0V*0.02A for Blue)) = 0.4W + 0.55W + 0.6W = 1.55W total. Using the thermal resistance, estimate the temperature rise and ensure it stays within the derating curve limits for the expected cabin ambient temperature (e.g., 85°C).
4. Color Control: Use a microcontroller to generate PWM signals for the driver IC's dimming inputs. Program look-up tables to produce desired colors (e.g., brand-specific ambient colors). Calibrate the PWM ratios for red, green, and blue in the final assembly to account for binning variations and achieve consistent white light across all doors.

11. Operating Principle Introduction

An LED (Light Emitting Diode) is a semiconductor device that emits light when an electric current passes through it. This phenomenon is called electroluminescence. The 5515-RGB020AH-AM contains three separate semiconductor chips (dice) within one package:
- The red chip is typically made from Aluminum Indium Gallium Phosphide (AlInGaP) material.
- The green and blue chips are typically made from Indium Gallium Nitride (InGaN) material.
Each chip has a p-n junction. When a forward voltage exceeding the chip's characteristic threshold is applied, electrons and holes recombine at the junction, releasing energy in the form of photons (light). The specific wavelength (color) of the light is determined by the bandgap energy of the semiconductor material. The light is then emitted through a molded epoxy lens which also provides mechanical protection and shapes the beam (120° angle). The three chips share a common cathode connection to simplify the external circuit.

12. Technology Trends

The development of LEDs like the 5515-RGB020AH-AM is driven by several clear trends in the industry:
1. Increased Integration and Miniaturization: Combining multiple colors (RGB, RGBW) into ever-smaller packages while maintaining or increasing light output.
2. Higher Efficiency (Lumens per Watt): Ongoing improvements in semiconductor epitaxy and chip design lead to more light output for the same electrical input, reducing power consumption and thermal load.
3. Enhanced Reliability and Robustness: Stricter standards for automotive, industrial, and outdoor applications drive improvements in materials (e.g., more robust lenses, corrosion-resistant finishes) and packaging to withstand higher temperatures, humidity, and thermal cycling.
4. Improved Color Quality and Consistency: Tighter binning tolerances and the development of LEDs with specific spectral characteristics to meet high-color-rendering-index (CRI) requirements for premium lighting.
5. Smart and Connected Lighting: LEDs are increasingly designed to be paired with integrated drivers and communication interfaces (like I2C or LIN in automotive) for dynamic, addressable color control, moving beyond simple analog dimming.