SMD5050 RGB Full-Color LED Datasheet - Dimensions 5.0x5.0x1.6mm - Voltage 2.2-3.4V - Power 0.846W - English Technical Document

1. Product Overview

The SMD5050-RGB is a high-performance, surface-mount, full-color LED designed for applications requiring vibrant color mixing and reliable operation. This device integrates red, green, and blue LED chips within a single 5.0mm x 5.0mm package, enabling the generation of a wide spectrum of colors through pulse-width modulation (PWM) or analog current control. Its primary applications include decorative lighting, architectural accent lighting, backlighting for displays, signage, and consumer electronics where dynamic color effects are desired.

The core advantage of this LED lies in its compact form factor that houses three distinct emitters, simplifying PCB design and assembly compared to using three separate discrete LEDs. It offers a typical wide viewing angle of 120 degrees, ensuring good color uniformity and visibility from various perspectives. The package is designed for compatibility with standard SMT (Surface Mount Technology) assembly processes, including reflow soldering.

2. Technical Parameters and Specifications

2.1 Absolute Maximum Ratings (Ta=25°C)

The following parameters define the stress limits beyond which permanent damage to the device may occur. Operation under or at these limits is not guaranteed.

• Forward Current (IF): 90 mA (continuous)
• Forward Pulse Current (IFP): 120 mA (Pulse width ≤10ms, Duty cycle ≤1/10)
• Power Dissipation (PD): 846 mW
• Operating Temperature (Topr): -40°C to +80°C
• Storage Temperature (Tstg): -40°C to +80°C
• Junction Temperature (Tj): 125°C
• Soldering Temperature (Tsld): 200°C or 230°C for 10 seconds (reflow profile)

2.2 Electro-Optical Characteristics (Ta=25°C)

These parameters define the typical performance under standard test conditions.

• Forward Voltage (Red, VF_R): Typical 2.2V, Maximum 2.6V (at IF=60mA)
• Forward Voltage (Green, VF_G): Typical 3.2V, Maximum 3.4V (at IF=60mA)
• Forward Voltage (Blue, VF_B): Typical 3.2V, Maximum 3.4V (at IF=60mA)
• Reverse Voltage (VR): 5 V
• Reverse Current (IR): Maximum 10 µA
• Viewing Angle (2θ1/2): 120 degrees

2.3 Wavelength Binning

The LEDs are classified into specific wavelength bins to ensure color consistency within an application. The dominant wavelength bins are as follows:

• Red (R): R1 (620-625nm), R2 (625-630nm)
• Green (G): G5 (519-522.5nm), G6 (522.5-526nm), G7 (526-530nm)
• Blue (B): B1 (445-450nm), B2 (450-455nm), B3 (455-460nm), B4 (460-465nm)

This binning allows designers to select LEDs with precise chromaticity coordinates for applications demanding specific color points or tight color matching across multiple units.

3. Performance Curves and Analysis

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

The I-V characteristic is fundamental for driver design. The red LED chip exhibits a lower forward voltage (typically ~2.2V) compared to the green and blue chips (typically ~3.2V), which is consistent with the different semiconductor materials used (e.g., AlInGaP for red vs. InGaN for green/blue). This disparity necessitates careful circuit design, often involving separate current-limiting resistors or independent constant-current channels for each color to achieve balanced brightness and proper color mixing. The curve shows a sharp turn-on, typical of diode behavior.

3.2 Relative Spectral Power vs. Junction Temperature

The spectral output of an LED shifts with changes in junction temperature. Generally, as the junction temperature increases, the dominant wavelength for InGaN-based LEDs (green/blue) tends to shift to longer wavelengths (red-shift), while the optical output power decreases. For AlInGaP-based red LEDs, the wavelength may also shift, and efficiency drops. This graph is crucial for applications operating in varying ambient temperatures or where thermal management is challenging, as it can affect the perceived color and light output. Proper heat sinking and thermal design are essential to maintain stable color performance.

4. Mechanical and Packaging Information

4.1 Dimensions and Outline Drawing

The package dimensions are 5.0mm (L) x 5.0mm (W) x 1.6mm (H). The drawing includes critical tolerances: .X dimensions have a tolerance of ±0.10mm, and .XX dimensions have a tolerance of ±0.05mm. The LED features six terminals (anode and cathode for each of the three color chips).

4.2 Recommended Footprint and Stencil Design

A recommended PCB land pattern (footprint) and solder paste stencil design are provided to ensure reliable solder joint formation during reflow. The footprint includes thermal relief patterns and appropriate pad sizes to facilitate good solder wetting and mechanical stability. Adhering to this recommended layout helps prevent tombstoning, misalignment, and insufficient solder joints.

5. Assembly, Handling, and Application Guidelines

5.1 Moisture Sensitivity and Baking

The SMD5050 package is moisture-sensitive (MSL classified per IPC/JEDEC J-STD-020C). If the original moisture barrier bag is opened and the components are exposed to ambient humidity beyond specified limits, absorbed moisture can vaporize during reflow soldering, potentially causing internal delamination or cracking ("popcorning").

• Storage: Store unopened bags at <30°C/<85% RH. After opening, store at <30°C/<60% RH and use within 12 hours.
• Baking: If exposure exceeds limits or the humidity indicator card shows high humidity, bake at 60°C for 24 hours before soldering. Do not exceed 60°C. Use within 1 hour after baking or store in a dry cabinet (<20% RH).

5.2 Electrostatic Discharge (ESD) Protection

LEDs are semiconductor devices susceptible to ESD damage, particularly the green, blue, and white (not applicable here) varieties. ESD can cause immediate failure (catastrophic) or latent damage leading to reduced lifetime and performance degradation.

• Precautions: Implement a full ESD control program: use grounded wrist straps, anti-static mats, ionizers, and conductive floorings. Handle LEDs only at ESD-protected workstations.
• Packaging: Use conductive or dissipative materials for transport and storage.

5.3 Circuit Design Recommendations

Proper drive circuitry is critical for performance and longevity.

• Current Limiting: Always use a series current-limiting resistor for each color channel. This stabilizes the current against variations in supply voltage and forward voltage (Vf) between individual LEDs.
• Driver Type: Constant-current drivers are strongly recommended over constant-voltage drivers for optimal stability and to prevent thermal runaway.
• Connection Polarity: Verify anode/cathode polarity before applying power. Reverse connection can damage the LED.
• Power Sequencing: When connecting, first connect the driver output to the LED, then apply input power to the driver to avoid voltage transients.

The datasheet illustrates two circuit configurations: one with a single resistor per parallel string (less ideal due to current imbalance if Vf varies) and one with an individual resistor for each LED (preferred for better current control).

5.4 Handling Precautions

Avoid direct handling of the LED lens with bare fingers. Skin oils can contaminate the silicone lens, causing optical degradation and reducing light output. Use vacuum pick-up tools or clean tweezers designed for component handling. Excessive mechanical force with tweezers can damage the wire bonds or the semiconductor die inside the package.

6. Ordering Information and Model Numbering

The product follows a specific part number coding system: T5A003FA. While the full decoding details for each segment are provided in the document (covering flux code, color temperature, internal code, chip count, lens code, and package outline), the key identifier "5050" confirms the package size, and "RGB" or "F" indicates the full-color (Red, Green, Blue) type.

7. Application Notes and Design Considerations

7.1 Thermal Management

Although the maximum junction temperature is 125°C, operating at lower temperatures significantly extends lifespan and maintains color stability. Ensure the PCB has adequate copper area for heat spreading. For high-power or high-density arrays, consider using metal-core PCBs (MCPCBs) or active cooling.

7.2 Color Mixing and Control

To achieve a specific white point or saturated color, precise control of the current ratio between the red, green, and blue channels is necessary. This is typically done via PWM dimming, which is more effective for color control than analog dimming, as it maintains the LED's optimal forward voltage and color characteristics. The different forward voltages require separate driver channels or carefully calculated resistor values for each color if using a common voltage supply with resistors.

7.3 Optical Design

The 120-degree viewing angle provides a wide, Lambertian-like emission pattern. For applications requiring directed light, secondary optics such as lenses or reflectors can be mounted above the LED. The silicone lens material is relatively soft; care must be taken not to scratch it during assembly.

8. Comparison and Differentiation

Compared to using three separate SMD LEDs (e.g., 3528 package), the integrated SMD5050 RGB offers a more compact solution, simplifies pick-and-place assembly (one component vs. three), and ensures precise spatial alignment of the three color points, which is critical for good color mixing at short distances. Compared to earlier RGB LED packages, the 5050 often provides higher light output and better thermal performance due to its larger footprint.

9. Frequently Asked Questions (FAQs)

9.1 Can I drive all three colors in parallel with one resistor?

No, this is not recommended. The forward voltages (Vf) of the red, green, and blue chips are different. Connecting them in parallel with a single resistor will cause severe current imbalance, with most current flowing through the channel with the lowest Vf (typically red), leading to incorrect colors and potential over-current in some chips.

9.2 Why is baking necessary, and can I use a higher temperature to bake faster?

Baking removes absorbed moisture to prevent damage during reflow. Do not exceed 60°C. Higher temperatures can degrade the internal materials (silicone, phosphors if present, adhesives) and the tape-and-reel packaging itself.

9.3 What is the typical lifespan of this LED?

The LED's lifespan (often defined as L70 - time to 70% of initial luminous flux) is highly dependent on operating conditions, primarily drive current and junction temperature. Operating at or below the recommended current (60mA per chip) and maintaining a low junction temperature through good thermal design can result in tens of thousands of hours of operation.

10. Practical Application Example

Scenario: Design of a color-changing LED strip.

1. Layout: Multiple SMD5050 RGB LEDs are placed along a flexible PCB strip at a defined pitch (e.g., 30 LEDs/meter).
2. Circuitry: Each LED's R, G, and B anodes are connected to common power rails (Vcc_R, Vcc_G, Vcc_B) via individual current-limiting resistors on the strip. The cathodes are connected to the drain of N-channel MOSFETs controlled by a microcontroller.
3. Control: The microcontroller generates PWM signals for each color channel of each LED group (often grouped in 3-LED segments for addressable strips like WS2812B, which integrates a controller chip). This allows independent color and brightness control for each segment.
4. Power: A 5V or 12V constant-voltage supply is used. The voltage and resistor values are chosen to provide the desired 60mA per chip, accounting for voltage drop along the strip.
5. Assembly: The strip is assembled using SMT processes, following the moisture sensitivity and ESD guidelines. After soldering, a silicone coating is often applied for waterproofing.

11. Operating Principle

An LED is a semiconductor p-n junction diode. When a forward voltage exceeding the diode's threshold is applied, electrons from the n-type region recombine with holes from the p-type region within the active layer. This recombination 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 materials used in the active region. The SMD5050 RGB integrates three such junctions, made from different material systems (e.g., AlInGaP for red, InGaN for green and blue), into one package. The light from each chip mixes externally to produce the perceived color.

12. Technology Trends

The general trend in RGB LEDs is toward higher efficiency (more lumens per watt), improved color rendering (wider gamut), and higher reliability. There is also a move toward tighter color and flux binning to ensure consistency in mass production. Integration with control electronics (e.g., creating "smart LEDs" or addressable LEDs with built-in ICs) is becoming increasingly common, simplifying system design for dynamic lighting applications. Furthermore, advancements in packaging materials aim to provide better thermal performance and long-term resistance to environmental factors like humidity and UV exposure.