White LED RF-A1P14-W892-A11 Specification - 2.20x1.40x1.30mm - 2.8V - 93mW - English Technical Document

1. Product Overview

This document details the specifications for a white light-emitting diode (LED) designed for surface-mount technology (SMT) applications. The device utilizes a blue LED chip combined with a phosphor coating to produce white light, encapsulated in a compact PLCC2 (Plastic Leaded Chip Carrier) package.

1.1 General Description

The LED is fabricated using a blue semiconductor chip and a phosphor conversion system. The final product is housed in a package measuring 2.20 mm in length, 1.40 mm in width, and 1.30 mm in height. This form factor is standardized for automated pick-and-place assembly processes.

1.2 Core Features and Advantages

• Package Type: Industry-standard PLCC2 package for reliable SMT assembly.
• Viewing Angle: Features an extremely wide viewing angle, providing uniform light distribution.
• Assembly Compatibility: Fully compatible with standard SMT assembly and solder reflow processes.
• Packaging: Supplied on tape and reel for automated manufacturing.
• Moisture Sensitivity: Rated at Moisture Sensitivity Level (MSL) 2.
• Environmental Compliance: Compliant with RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations.
• Quality Standards: The product qualification test plan follows the guidelines of AEC-Q101, the stress test qualification standard for automotive-grade discrete semiconductors.

1.3 Target Market and Application

The primary application for this LED is Automotive Lighting Interior. This includes dashboard illumination, switch backlighting, ambient lighting, and other interior lighting functions where reliability, compact size, and consistent white light output are critical.

2. In-Depth Technical Parameter Analysis

2.1 Electrical and Optical Characteristics

The following parameters are specified at an ambient temperature (Ts) of 25°C.

• Forward Voltage (VF): Typically 2.8V, with a range from 2.5V to 3.1V when driven at a forward current (IF) of 5mA. The measurement tolerance is ±0.1V.
• Reverse Current (IR): Maximum of 10 µA when a reverse voltage (VR) of 5V is applied.
• Luminous Intensity (IV): Typically 53 millicandelas (mcd), ranging from 43 mcd to 65 mcd at IF=5mA. The measurement tolerance is ±10%.
• Viewing Angle (2θ1/2): Typically 120 degrees, indicating a very broad emission pattern.
• Thermal Resistance (RθJ-S): Junction-to-solder point thermal resistance is a maximum of 300 °C/W. This parameter is crucial for thermal management design.

2.2 Absolute Maximum Ratings

These ratings define the limits beyond which permanent damage to the device may occur. Operation at or near these limits is not recommended.

• Power Dissipation (PD): 93 mW.
• Continuous Forward Current (IF): 30 mA.
• Peak Forward Current (IFP): 100 mA (pulsed, 1/10 duty cycle, 10ms pulse width).
• Reverse Voltage (VR): 5 V.
• Electrostatic Discharge (ESD) Withstand: 8000 V (Human Body Model). Over 90% yield is guaranteed at this level, but ESD protection during handling is still required.
• Operating Temperature (TOPR): -40°C to +100°C.
• Storage Temperature (TSTG): -40°C to +100°C.
• Maximum Junction Temperature (TJ): 120°C. The operating current must be derated to ensure the junction temperature does not exceed this limit.

3. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins based on key parameters.

3.1 Forward Voltage (VF) Binning

At a test current of 5mA, LEDs are categorized into six voltage bins: E2 (2.5-2.6V), F1 (2.6-2.7V), F2 (2.7-2.8V), G1 (2.8-2.9V), G2 (2.9-3.0V), H1 (3.0-3.1V). This allows designers to select LEDs with tighter voltage tolerances for applications requiring uniform current distribution in parallel strings.

3.2 Luminous Intensity (IV) Binning

At IF=5mA, luminous intensity is binned into two groups: E1 (43-53 mcd) and E2 (53-65 mcd). This binning helps achieve consistent brightness levels in an assembly.

3.3 Chromaticity Coordinate Binning

The white light color is defined by its coordinates on the CIE 1931 chromaticity diagram. Three primary bins are defined (TG1, TG2, TG3), each specifying a quadrilateral area on the chart. The coordinates for the corners of these areas are provided in a table. This system ensures the white point falls within a controlled, predictable region, critical for applications where color matching is important.

4. Performance Curve Analysis

4.1 Forward Voltage vs. Forward Current (IV Curve)

The characteristic curve shows the relationship between forward voltage (Vf) and forward current (If). It is non-linear, typical of a diode. The curve indicates that at the typical operating point of 5mA, the voltage is around 2.8V. Designers use this curve to determine the necessary drive voltage for a desired current, which is essential for designing constant-current LED drivers.

4.2 Relative Luminous Intensity vs. Forward Current

This curve demonstrates how light output increases with drive current. The relationship is generally linear at lower currents but may saturate at higher currents due to thermal and efficiency effects. It helps in selecting the appropriate drive current to achieve target brightness while maintaining efficiency and longevity.

4.3 Solder Temperature vs. Relative Intensity

This graph (partially shown) is critical for understanding the LED's resilience during the reflow soldering process. It likely shows the change in light output before and after exposure to high soldering temperatures. A stable curve indicates good package integrity and phosphor stability, ensuring performance is not degraded by the assembly process.

5. Mechanical and Package Information

5.1 Package Dimensions and Tolerances

The LED package has precise dimensions: 2.20mm (L) x 1.40mm (W) x 1.30mm (H). All dimensional tolerances are ±0.20mm unless otherwise specified. Detailed top, side, and bottom views are provided in the specification, showing the lens shape, lead frame, and marking.

5.2 Polarity Identification and Soldering Pattern

The cathode (negative terminal) is clearly marked on the package. A recommended soldering land pattern (footprint) is provided for PCB design. Adhering to this pattern ensures proper solder joint formation, alignment, and thermal performance during reflow.

6. Soldering and Assembly Guidelines

6.1 SMT Reflow Soldering Instructions

A dedicated section outlines the procedures for SMT reflow soldering. While specific temperature profiles are not detailed in the provided excerpt, this section typically includes recommendations for preheating, peak temperature, time above liquidus, and cooling rates compatible with the PLCC2 package and MSL 2 rating. Following these guidelines is essential to prevent thermal shock, delamination, or solder defects.

6.2 Handling Precautions

General handling precautions are emphasized. Key points include:

• ESD Protection: Despite a high ESD withstand rating, proper ESD controls (grounded workstations, wrist straps) are mandatory during handling to prevent latent damage.
• Moisture Sensitivity: As an MSL 2 device, the LEDs must be baked if the moisture barrier bag is opened and the components are exposed to ambient conditions for longer than the specified floor life (typically 1 year at <10% RH, or 1 week at <60% RH) before reflow.
• Mechanical Stress: Avoid applying excessive force to the lens or leads.
• Contamination: Keep the lens clean and free from flux residues or other contaminants that can affect light output.

7. Packaging and Reliability

7.1 Packaging Specification

The LEDs are supplied on embossed carrier tape wound onto reels. The specification includes detailed dimensions for the carrier tape pockets, reel diameter, and hub size to ensure compatibility with standard SMT placement equipment. A label form specification ensures traceability with lot codes, part numbers, and quantities.

7.2 Moisture Resistant Packing and Storage

The reels are packaged in moisture barrier bags with desiccant and a humidity indicator card to maintain the MSL 2 rating during storage and transport.

7.3 Reliability Test Items and Conditions

A list of reliability tests is referenced, based on AEC-Q101. These tests likely include High Temperature Operating Life (HTOL), Temperature Cycling (TC), High Temperature High Humidity Reverse Bias (H3TRB), and others. These tests validate the LED's performance and longevity under harsh automotive environmental conditions.

7.4 Criteria for Judging Damage

Clear pass/fail criteria are defined for post-reliability-test inspection. This typically involves checking for catastrophic failures (no light output), significant parametric shifts (e.g., luminous intensity drop > 50%, Vf shift > 10%), and visual defects (cracks, discoloration, delamination).

8. Application Design Considerations

8.1 Thermal Management

With a thermal resistance of 300 °C/W and a maximum junction temperature of 120°C, effective heat sinking is crucial. The PCB layout must provide adequate thermal relief, especially when operating at currents above 5mA. The maximum forward current should be determined by measuring the actual package temperature in the application to ensure Tj < 120°C. Exceeding Tj max drastically reduces lifetime.

8.2 Current Driving

For stable and long-life operation, driving the LED with a constant current source is strongly recommended, not a constant voltage. This compensates for the negative temperature coefficient of Vf and ensures consistent light output. The driver should be designed based on the IV curve and the desired brightness level.

8.3 Optical Design

The 120-degree viewing angle makes this LED suitable for applications requiring wide, diffuse illumination rather than a focused beam. For more directional light, secondary optics (lenses, reflectors) would be required. The small package size allows for high-density lighting arrays.

9. Technical Comparison and Differentiation

This LED differentiates itself through its automotive-grade qualification (AEC-Q101). While many PLCC2 white LEDs exist, those qualified to automotive standards undergo more rigorous testing for temperature extremes, humidity, vibration, and long-term reliability. This makes it a preferred choice for automotive interior applications where failure is not an option. The combination of a wide viewing angle, compact size, and proven reliability in a harsh environment forms its core competitive advantage over commercial-grade components.

10. Frequently Asked Questions (FAQ)

10.1 What is the recommended operating current?

While the absolute maximum continuous current is 30mA, the typical test and characterization data is provided at 5mA. The optimal operating current depends on the required brightness, thermal design, and lifetime targets. For most applications, operating between 5mA and 20mA provides a good balance of output, efficiency, and longevity. Always refer to the derating curves based on ambient temperature.

10.2 How do I interpret the voltage bin codes?

Voltage bins (E2, F1, F2, etc.) allow you to select LEDs with similar forward voltages. This is particularly important when connecting multiple LEDs in parallel. Using LEDs from the same or adjacent voltage bins helps ensure more uniform current sharing between them, leading to consistent brightness and preventing one LED from hogging current.

10.3 Is a heatsink required?

For low-current operation (e.g., 5mA indicator use), a dedicated heatsink is often not necessary if the PCB provides some copper pour for heat spreading. For higher current operation or high ambient temperatures, thermal analysis is mandatory. The high thermal resistance (300°C/W) means that even a few tens of milliwatts of power dissipation can cause a significant temperature rise at the junction. Proper PCB thermal design is the primary heatsink.

11. Practical Design and Usage Case

Case: Dashboard Illumination Cluster

A designer is creating backlighting for an automotive instrument cluster. They need small, reliable white LEDs for illuminating icons and gauges. They select this LED for its AEC-Q101 qualification and wide viewing angle. They design a PCB with a copper pad under the LED's thermal pad for heat dissipation. They drive groups of 3 LEDs in series with a constant current driver set to 15mA per string, achieving the desired brightness. They specify LEDs from the same luminous intensity bin (E2) and chromaticity bin (TG2) to ensure uniform color and brightness across the entire cluster. The tape-and-reel packaging allows for fully automated assembly on their SMT line.

12. Operating Principle Introduction

This is a phosphor-converted white LED. The core is a semiconductor chip made of materials like indium gallium nitride (InGaN) that emits blue light when electrical current passes through it (electroluminescence). This blue chip is coated with a layer of yellow phosphor (often based on yttrium aluminum garnet, or YAG). Part of the blue light from the chip is absorbed by the phosphor and re-emitted as yellow light. The remaining blue light mixes with the yellow light, and the human eye perceives this combination as white light. The exact shade of white (cool, neutral, warm) is determined by the ratio of blue to yellow light, which is controlled by the phosphor composition and thickness.

13. Technology Trends

The trend in SMD LEDs for automotive and general lighting continues towards:

Higher Efficiency (lm/W): Reducing energy consumption for the same light output.

Improved Color Rendering (CRI): Achieving more natural and accurate color reproduction under the LED light.

Higher Reliability and Power Density: Pushing the limits of operating temperature and current density while maintaining long lifetimes, especially for under-hood or exterior automotive applications.

Miniaturization: Even smaller package sizes (e.g., 1.0mm x 0.5mm) for space-constrained designs.

Integrated Solutions: LEDs with built-in current-limiting resistors, Zener diodes for reverse voltage protection, or even IC drivers for simplified circuit design. The component described here represents a mature, reliable solution in this evolving landscape.