SMD RGB LED with Embedded IC - 5.0x5.0x1.6mm - Voltage 4.2-5.5V - Power 99mW - English Technical Datasheet

1. Product Overview

This document details the specifications for a surface-mount device (SMD) LED that integrates red, green, and blue (RGB) semiconductor chips with an embedded 8-bit driver integrated circuit (IC) within a single package. This integrated solution is designed to simplify constant current applications for designers, eliminating the need for external current-limiting resistors or complex driver circuits for each color channel.

1.1 Core Advantages and Product Positioning

The primary advantage of this component is its high level of integration. By combining the control logic and RGB emitters, it forms a complete, addressable pixel point. This architecture is particularly beneficial for applications requiring multiple LEDs, such as LED strips, matrix displays, and decorative lighting, as it significantly reduces component count, board space, and system complexity. The device is packaged in a standard EIA-compliant footprint, making it compatible with automated pick-and-place and infrared reflow soldering processes, which is crucial for high-volume manufacturing.

1.2 Target Applications and Markets

This LED is engineered for a broad spectrum of electronic equipment where space, efficiency, and color control are paramount. Its key application areas include:

• Full-Color Modules and Soft Lighting: Ideal for creating dynamic color-changing effects in lamp strips, architectural accent lighting, and mood lighting systems.
• Indoor Displays and Signage: Suitable for irregular video displays, informational signs, and decorative panels where individual pixel control is required.
• Consumer Electronics: Can be used for status indicators, front panel backlighting, or aesthetic lighting in devices such as networking equipment, home appliances, and computer peripherals.
• Industrial & Office Equipment: Applicable for status signaling and operator interface illumination in various industrial and office automation contexts.

2. Technical Parameters: In-Depth Objective Analysis

The following sections provide a detailed, objective breakdown of the device's key performance characteristics as defined in the datasheet.

2.1 Absolute Maximum Ratings and Operating Limits

These parameters define the stress limits beyond which permanent damage to the device may occur. They are not intended for normal operation.

• Power Dissipation (P_D): 99 mW. This is the maximum total power the package can dissipate as heat. Exceeding this limit risks overheating and failure.
• Supply Voltage Range (V_DD): +4.2V to +5.5V. The embedded IC requires a regulated supply within this range for reliable operation. Applying voltage outside this range can damage the control circuitry.
• Total Forward Current (I_F): 18 mA. This is the maximum sum of currents flowing through the Red, Green, and Blue chips simultaneously.
• Temperature Ranges: The device is rated for operation from -40°C to +85°C and can be stored in environments from -40°C to +100°C.

2.2 Optical Characteristics

Measured at an ambient temperature (T_a) of 25°C with a supply voltage (V_DD) of 5V and all color channels set to maximum brightness (8'b11111111).

• Luminous Intensity (I_V): This is the perceived brightness of the light output. The typical values are: Red: 100-200 mcd, Green: 250-500 mcd, Blue: 50-120 mcd. The green chip typically exhibits the highest luminous intensity.
• Viewing Angle (2θ_1/2): 120 degrees. This wide viewing angle, characteristic of a diffused lens, means the LED emits light over a broad area, making it suitable for applications where visibility from multiple angles is important.
• Dominant Wavelength (λ_d): This parameter defines the perceived color of the light. The specified ranges are: Red: 615-630 nm, Green: 520-535 nm, Blue: 460-475 nm. These ranges place the colors within standard visible spectral bands for red, green, and blue.

2.3 Electrical Characteristics

Defined for an ambient temperature range of -20°C to +70°C, V_DD from 4.2V to 5.5V, and V_SS at 0V.

• IC Output Current (I_F): 5 mA (typical). This is the constant current supplied by the embedded driver IC to each individual Red, Green, and Blue LED chip. This constant current design ensures stable color output and protects the LEDs from current spikes.
• Input Logic Levels: For the data input (DIN) pin, a logic high (V_IH) is recognized at 2.7V minimum up to V_DD. A logic low (V_IL) is recognized at 1.0V maximum. This is compatible with 3.3V and 5V microcontroller logic.
• IC Quiescent Current (I_DD): 0.8 mA (typical) when all LED data is set to '0' (off). This is the power consumed by the embedded IC itself when the LEDs are not illuminated.

3. Data Transmission Protocol and Control

The device features a single-wire, cascadable communication protocol, allowing multiple units to be daisy-chained and controlled from a single microcontroller pin.

3.1 Protocol Fundamentals

Data is transmitted as a sequence of high and low pulses on the DIN pin. Each bit ('0' or '1') is encoded by a specific timing pattern within a nominal period of 1.2 µs (±300ns).

• '0' Bit: High time (T_0H) = 300 ns ±150ns, followed by Low time (T_0L) = 900 ns ±150ns.
• '1' Bit: High time (T_1H) = 900 ns ±150ns, followed by Low time (T_1L) = 300 ns ±150ns.

The timing tolerance allows for some variation in microcontroller clock speeds but requires precise software or hardware timing for reliable communication.

3.2 Data Frame Structure

Each LED requires 24 bits of data to set its color. The data is sent in the order: Green (8 bits), Red (8 bits), Blue (8 bits). Each 8-bit value controls the brightness of that specific color channel with 256 steps (0-255). This allows for the creation of 16,777,216 (256^3) possible color combinations.

3.3 Cascading and Reset

Data sent into the DIN pin of the first LED is shifted through its internal register and then output on its DOUT pin after 24 bits. This DOUT can be connected to the DIN of the next LED in the chain, allowing an unlimited number of LEDs to be controlled serially. A low signal on the DIN pin lasting longer than 250 µs (RESET time) causes all LEDs in the chain to latch the data currently in their registers and display it, then prepare to receive new data starting with the first LED in the chain.

4. Color Binning System

The datasheet provides a CIE 1931 chromaticity diagram-based binning table to categorize the color output of the white diffused LED. The bin codes (A, B, C, D) define quadrilaterals on the (x, y) color coordinate plane, each with a tolerance of ±0.01. This system allows manufacturers and designers to select LEDs with consistent color characteristics for applications where color uniformity across multiple units is critical, such as in large displays or lighting panels.

5. Performance Curve Analysis

The datasheet includes graphical representations of key performance relationships.

5.1 Relative Intensity vs. Wavelength (Spectral Distribution)

This curve shows the emission spectrum of each color chip (Red, Green, Blue). It typically displays distinct peaks corresponding to the dominant wavelengths. The width of these peaks indicates the spectral purity; narrower peaks suggest more saturated colors. The overlap between color spectra, particularly in the green-yellow region, will influence the quality and range of mixed colors (e.g., creating a pure yellow from red and green).

5.2 Forward Current vs. Ambient Temperature Derating Curve

This graph is crucial for thermal management. It shows the maximum allowable forward current per LED chip as a function of the ambient temperature. As temperature increases, the maximum safe current decreases. For example, at 25°C, the maximum current might be near the rated 18mA, but at 85°C, the maximum permissible current is significantly lower. Designers must ensure the operating current, especially when all three colors are at full brightness, does not exceed the derated limit at the highest expected ambient temperature to ensure long-term reliability.

5.3 Spatial Distribution (Radiation Pattern)

This polar plot illustrates how light intensity varies with the viewing angle relative to the LED's central axis. The provided 120-degree viewing angle (2θ_1/2) is the point where intensity drops to 50% of the on-axis value. The diffused lens creates a Lambertian-like pattern, providing even illumination over a wide area rather than a focused beam.

6. Mechanical and Packaging Information

6.1 Package Dimensions and Configuration

The device has a nominal footprint of 5.0 mm x 5.0 mm with a height of 1.6 mm. All dimensional tolerances are ±0.2 mm unless otherwise specified. A top-view diagram identifies the four pins: 1 (VDD - Power), 2 (DIN - Data Input), 3 (VSS - Ground), and 4 (DOUT - Data Output).

6.2 Recommended PCB Attachment Pad Layout

A land pattern diagram is provided to guide PCB design. Adhering to these recommended pad dimensions and spacing is essential for achieving reliable solder joints during the reflow process and ensuring proper mechanical stability.

7. Assembly and Handling Guidelines

7.1 Soldering Process

The device is compatible with infrared (IR) reflow soldering processes suitable for lead-free (Pb-free) solder. The datasheet references a profile according to the J-STD-020B standard. Key parameters in such a profile include preheat, soak, reflow peak temperature (which must not exceed the device's maximum temperature rating), and cooling rate. Following the recommended profile is critical to prevent thermal shock, solder joint defects, or damage to the LED package and internal IC.

7.2 Cleaning

If post-assembly cleaning is necessary, the recommended method is to immerse the assembled board in ethyl alcohol or isopropyl alcohol at room temperature for less than one minute. The use of unspecified or aggressive chemical cleaners is prohibited as they may damage the plastic lens or the package material.

8. Packaging and Ordering

The LEDs are supplied on 8mm wide embossed carrier tape wound onto 7-inch (178mm) diameter reels. Standard packing quantity is 4000 pieces per reel. The tape and reel specifications conform to ANSI/EIA 481 standards, ensuring compatibility with automated assembly equipment. Detailed dimensional drawings for the tape pockets and the reel are provided for logistics and machine setup purposes.

9. Application Design Considerations

9.1 Power Supply Design

A stable, low-noise power supply within the 4.2V to 5.5V range is essential. The total current demand for a string of LEDs must be calculated: I_total = (Number of LEDs) * (I_{DD_quiescent}) + (Number of Lit Pixels) * (I_{F_R} + I_{F_G} + I_{F_B}). For large installations, consider voltage drop along the power lines, which may require power injection at multiple points.

9.2 Data Signal Integrity

For long daisy chains or in electrically noisy environments, signal integrity on the data line (DIN/DOUT) can degrade. Strategies to mitigate this include using a lower data rate (if timing allows), adding a small series resistor (e.g., 100-470 Ω) at the microcontroller output to reduce ringing, and ensuring a solid, low-impedance ground connection throughout the system.

9.3 Thermal Management

While the constant current driver provides inherent protection, the power dissipated as heat (P = V_f * I_f for each chip, plus IC loss) must be managed. Ensure adequate ventilation or heatsinking if LEDs are operated at high brightness levels or in high ambient temperatures, especially in densely packed arrays. Refer to the derating curve in section 5.2.

10. Technical Comparison and Differentiation

The key differentiator of this component is the embedded constant current driver IC. Compared to a standard RGB LED which requires three external current-limiting resistors and an external multiplexing or PWM driver circuit, this integrated solution offers significant advantages:

• Simplified Design: Reduces Bill of Materials (BOM) and PCB layout complexity.
• Improved Consistency: The on-chip constant current source provides identical drive conditions for each color in every unit, leading to better color uniformity across a production run.
• Cascadability: The single-wire protocol allows control of hundreds of LEDs from one microcontroller pin, vastly simplifying wiring and control software for large installations.
• High Color Depth: 8-bit (256-step) control per color channel enables smooth gradients and a vast color palette, which is superior to simpler multiplexed or analog-controlled solutions.

11. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I power this LED directly from a 3.3V microcontroller supply?
A: No. The absolute minimum supply voltage (V_DD) is 4.2V. A 3.3V supply is below the operating range and will not power the embedded IC correctly. You need a separate 5V (or 4.2-5.5V) power rail for the LEDs.

Q: How do I calculate the current required for my project with 100 of these LEDs?
A: You must consider two components: 1) Quiescent current for the ICs: 100 LEDs * 0.8 mA = 80 mA. 2) LED current: This depends on the colors displayed. In the worst-case scenario (all LEDs showing full-brightness white), each LED draws ~15 mA (3 colors * 5 mA). So, 100 LEDs * 15 mA = 1500 mA. Total worst-case current ≈ 1580 mA or 1.58A at 5V. Your power supply must be rated for this.

Q: What happens if the data signal timing is slightly outside the specified tolerance?
A: The device may misinterpret the data, leading to incorrect colors being displayed or a complete failure of communication down the chain. It is critical to generate the data signal with timing as close to the typical values as possible, staying within the ±150ns allowances.

Q: Is a heatsink required?
A: It depends on the operating conditions. At room temperature and moderate brightness, the 99mW power dissipation rating is likely sufficient. However, if operating in a high ambient temperature enclosure or at maximum brightness continuously, thermal analysis should be performed. The derating curve in section 5.2 shows that maximum current must be reduced as temperature rises, which is an indirect form of thermal management.

12. Practical Application Example

Scenario: Designing a 10x10 RGB LED Matrix Panel for an Art Installation.

Design Steps:
1. Layout: Arrange 100 LEDs in a grid. Connect all VDD pins to a common 5V power plane and all VSS pins to a common ground plane.
2. Power: Calculate peak power: 100 LEDs * (0.015A * 5V) = 7.5W. Select a 5V, 8A (40W) power supply with ~20% headroom. Plan for power injection from multiple sides of the panel to minimize voltage drop.
3. Data Chain: Connect the DOUT of each LED in a row to the DIN of the next LED in the same row. At the end of each row, the DOUT can be connected to the DIN of the first LED in the next row, creating a single long chain of 100 LEDs.
4. Control: A microcontroller (e.g., ESP32, Arduino) generates the data stream. The software must send 2400 bits (100 LEDs * 24 bits) of color data, followed by a reset pulse >250 µs to make the LEDs update. Libraries exist to simplify this protocol.
5. Thermal: Mount the LEDs on an aluminum PCB or ensure the panel has ventilation, as 7.5W of heat in a confined space will raise the ambient temperature, triggering the need for current derating.

13. Operational Principle

The device operates on a simple but effective principle. The embedded IC contains a shift register and constant current sinks. Serial data clocked into the DIN pin is shifted through the internal 24-bit register. Once a reset signal is received, the IC latches this data. Each 8-bit segment of the latched data controls a Pulse Width Modulation (PWM) generator for one color channel (Red, Green, Blue). The PWM signal then drives a constant current sink connected to the corresponding LED chip. A value of 255 (8'b11111111) results in a 100% duty cycle (fully on), while a value of 127 results in a ~50% duty cycle, thereby controlling brightness. The constant current sink ensures the LED receives a stable current regardless of minor forward voltage (V_f) variations between chips or with temperature.

14. Technology Trends and Context

This component represents a clear trend in LED technology: increased integration and intelligence at the package level. Moving driver functionality onto the same substrate as the emitter (a concept often called \"LEDs with integrated circuits\" or \"smart LEDs\") addresses several industry challenges. It reduces system cost and complexity for end-users, improves performance consistency, and enables new applications like easily scalable, high-resolution addressable displays. This trend is evolving towards LEDs with more advanced integrated circuits capable of higher data rates (e.g., for video), built-in memory for patterns, and even sensors for ambient light or temperature feedback, paving the way for more autonomous and adaptive lighting systems.