SMD Middle Power Yellow LED 67-21S Specification - PLCC-2 Package - 150mA - 2.8V - 590-600nm - English Technical Document

1. Product Overview

This document details the specifications for a surface-mount device (SMD) middle power light-emitting diode (LED) in a PLCC-2 package format. The device is characterized by its yellow light emission, achieved through an AlGaInP chip material encapsulated in water-clear resin. It is designed for general lighting applications requiring a balance of performance, efficiency, and compact form factor.

The core advantages of this LED include high luminous efficacy, moderate power consumption suitable for mid-power applications, and a wide viewing angle of 120 degrees, ensuring uniform light distribution. The product adheres to modern environmental and safety standards, being lead-free (Pb-free), compliant with the Restriction of Hazardous Substances (RoHS) directive, EU REACH regulations, and halogen-free requirements (Br<900ppm, Cl<900ppm, Br+Cl<1500ppm). Its compact design makes it an ideal component for space-constrained lighting solutions.

1.1 Target Applications

The primary application areas for this LED are diverse, leveraging its color and performance characteristics. Key markets include Decorative and Entertainment Lighting, where consistent yellow output is desirable for aesthetic effects. It is also suitable for Agriculture Lighting applications, potentially for specific growth stages or supplemental lighting. Finally, its balanced performance profile makes it applicable for General Use lighting in various consumer and commercial products.

2. Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device's operational limits are defined under conditions where the soldering point temperature (T_Soldering) is 25°C. Exceeding these ratings may cause permanent damage.

• Forward Current (I_F): 150 mA (Continuous).
• Peak Forward Current (I_FP): 300 mA, permissible under pulsed conditions with a duty cycle of 1/10 and a pulse width of 10ms.
• Power Dissipation (P_d): 420 mW.
• Electrostatic Discharge (ESD) Human Body Model (HBM): 2000 V. The component is sensitive to static electricity, and proper ESD handling precautions are mandatory. This rating is for reference.
• Operating Temperature (T_opr): -40°C to +85°C.
• Storage Temperature (T_stg): -40°C to +100°C.
• Thermal Resistance, Junction to Soldering Point (R_{th J-S}): 50 °C/W. This parameter is critical for thermal management design.
• Maximum Junction Temperature (T_j): 115 °C.
• Soldering Temperature: The device can withstand reflow soldering at 260°C for 10 seconds or hand soldering at 350°C for 3 seconds.

2.2 Electro-Optical Characteristics

Typical performance is measured at T_Soldering = 25°C and I_F = 150 mA.

• Luminous Flux (Φ): Ranges from a minimum of 11 lm to a maximum of 27 lm, with a typical tolerance of ±11%.
• Forward Voltage (V_F): Ranges from 1.8 V to 2.8 V at the specified current, with a typical tolerance of ±0.1V.
• Viewing Angle (2θ_1/2): 120 degrees, typical.
• Reverse Current (I_R): Maximum of 50 µA when a reverse voltage (V_R) of 5V is applied.

3. Binning System Explanation

To ensure consistency in production, LEDs are sorted into bins based on key performance parameters. This allows designers to select components that meet specific application requirements for brightness and electrical characteristics.

3.1 Luminous Flux Binning

LEDs are categorized by their light output measured at I_F=150mA. The bin codes (e.g., L2, L3, M3, N3) define a minimum and maximum luminous flux range. For example, bin L2 covers 11-12 lm, while bin N3 covers 24-27 lm. The tolerance within each bin is ±11%.

3.2 Forward Voltage Binning

Devices are also binned according to their forward voltage drop at I_F=150mA. Bin codes from 25 to 34 represent voltage ranges in 0.1V steps, starting from 1.8-1.9V (Bin 25) up to 2.7-2.8V (Bin 34). The tolerance is ±0.1V.

3.3 Dominant Wavelength Binning

This defines the perceived color of the yellow light. Two bins are specified: Y53 (590-595 nm) and Y54 (595-600 nm). The measurement tolerance for dominant/peak wavelength is ±1 nm.

4. Performance Curve Analysis

The datasheet provides several graphs illustrating the device's behavior under varying conditions.

4.1 Spectral Distribution

A graph shows the relative luminous intensity across wavelengths from approximately 520 nm to 680 nm. The curve peaks in the yellow region (around 590-600 nm), confirming the dominant wavelength bins, with minimal emission in other parts of the visible spectrum.

4.2 Thermal and Electrical Characteristics

• Forward Voltage vs. Junction Temperature (Fig.1): Shows how V_F decreases linearly with increasing junction temperature (T_j), a common characteristic of LEDs. This is important for constant-current drive design.
• Relative Radiometric Power vs. Forward Current (Fig.2): Illustrates the sub-linear relationship between light output and drive current. Efficiency typically decreases at very high currents.
• Relative Luminous Flux vs. Junction Temperature (Fig.3): Demonstrates the reduction in light output as T_j increases, highlighting the importance of thermal management to maintain brightness.
• Forward Current vs. Forward Voltage (Fig.4): The standard I-V curve for a diode, showing the exponential relationship.
• Max. Driving Forward Current vs. Soldering Temperature (Fig.5): A derating curve indicating that the maximum allowable continuous forward current must be reduced as the ambient/soldering point temperature increases to prevent exceeding T_j(max).
• Radiation Diagram (Fig.6): A polar plot depicting the spatial distribution of light intensity, confirming the wide 120-degree viewing angle with a near-Lambertian pattern.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED is housed in a standard PLCC-2 (Plastic Leaded Chip Carrier) surface-mount package. The dimensional drawing specifies the length, width, height, lead spacing, and other critical mechanical features. Unless otherwise noted, the dimensional tolerance is ±0.15 mm. The package is designed for compatibility with automated pick-and-place and reflow soldering processes.

6. Soldering and Assembly Guidelines

6.1 Soldering Parameters

The device is rated for standard soldering processes: Reflow soldering at a peak temperature of 260°C for a duration of 10 seconds, or hand soldering at 350°C for 3 seconds. Adherence to these profiles is necessary to prevent package damage or degradation of internal materials.

6.2 Storage and Handling Precautions

• ESD Sensitivity: The product is sensitive to electrostatic discharge. Proper ESD-safe handling procedures must be followed during all stages of assembly and testing.
• Moisture Sensitivity: The components are packaged in moisture-resistant materials (aluminum moisture-proof bags with desiccant). The bag should not be opened until the products are ready for use in a production environment. If exposed, baking may be required per industry standards (though specific conditions are not detailed here).
• Current Protection: An external current-limiting resistor or constant-current driver is mandatory. LEDs exhibit a sharp rise in current with a small increase in voltage beyond their forward voltage, which can lead to thermal runaway and failure if not properly controlled.

7. Packaging and Ordering Information

7.1 Reel and Tape Specifications

The LEDs are supplied on embossed carrier tape wound onto reels for automated assembly. Key specifications include reel dimensions, tape width, pocket spacing, and the progressive direction. A standard reel contains 4000 pieces. Detailed drawings for the reel, carrier tape, and cover tape dimensions are provided, with tolerances typically ±0.1 mm.

7.2 Label Explanation

The packaging label includes several codes: CPN (Customer's Product Number), P/N (Product Number), QTY (Packing Quantity), CAT (Luminous Intensity Rank, corresponding to flux bin), HUE (Dominant Wavelength Rank), REF (Forward Voltage Rank), and LOT No (Lot Number for traceability).

8. Application Suggestions and Design Considerations

8.1 Design Considerations

• Thermal Management: With a thermal resistance (R_{th J-S}) of 50 °C/W, effective heat sinking from the soldering pads is crucial, especially when operating at or near the maximum current of 150 mA. The derating curve (Fig.5) must be consulted for high ambient temperature applications.
• Drive Circuitry: Always use a constant-current source or a voltage source with a series resistor to set the current. The forward voltage has both a range (1.8-2.8V) and a negative temperature coefficient, making voltage-driven designs unstable.
• Optical Design: The wide 120-degree viewing angle is beneficial for applications requiring broad illumination without secondary optics. For focused beams, appropriate primary optics (lenses) must be selected.

8.2 Binning for Application Consistency

For applications where color or brightness uniformity is critical (e.g., multi-LED arrays in decorative lighting), specifying tight bins for luminous flux (Φ), forward voltage (V_F), and dominant wavelength is essential. Using LEDs from the same manufacturing lot can further enhance consistency.

9. Reliability and Quality Assurance

A comprehensive set of reliability tests is performed to ensure product longevity and robustness under various environmental stresses. The tests are conducted with a confidence level of 90% and a Lot Tolerance Percent Defective (LTPD) of 10%. Sample size for each test is 22 pieces, with an Accept/Reject criterion of 0/1.

9.1 Reliability Test Items

The test regimen includes: Reflow Soldering Resistance, Thermal Shock, Temperature Cycling, High Temperature/Humidity Storage, High Temperature/Humidity Operation, Low Temperature Storage, High Temperature Storage, and multiple High/Low Temperature Operation Life tests under different current and temperature conditions (e.g., 150mA at 25°C, 55°C, and 90mA at 85°C). These tests simulate real-world operating conditions and accelerated aging.

10. Technical Comparison and Positioning

As a middle power LED in a PLCC-2 package, this device occupies a specific niche. Compared to low-power LEDs (e.g., 0603, 0805 packages), it offers significantly higher light output, making it suitable for primary illumination rather than just indicators. Compared to high-power LEDs (e.g., 1W, 3W packages on metal-core PCBs), it operates at lower currents and has a simpler thermal management requirement, often dissipating heat through the PCB traces alone. Its key differentiators are the combination of good efficacy, a compact and standardized package, wide viewing angle, and compliance with stringent environmental regulations.

11. Frequently Asked Questions (Based on Technical Parameters)

11.1 What is the typical operating current?

The electro-optical characteristics are specified at 150 mA, which is also the maximum continuous forward current. This is the standard test and recommended operating point for achieving the rated luminous flux.

11.2 Why is a constant current driver necessary?

The forward voltage (V_F) has a production spread (1.8-2.8V) and decreases with temperature. Driving with a fixed voltage would cause large variations in current and thus light output, potentially exceeding the absolute maximum rating and causing failure. A constant current source ensures stable brightness and protects the LED.

11.3 How do I interpret the bin codes in an order?

The full part number includes codes for luminous flux (e.g., L8), forward voltage (e.g., 28), and dominant wavelength (e.g., Y54). This specifies a device with flux between 17-18 lm, V_F between 2.1-2.2V, and a wavelength between 595-600 nm. Designers should select bins that match their circuit design (for voltage) and application requirements (for brightness and color).

11.4 What are the storage conditions before use?

The components are moisture-sensitive. They must be stored in their original, unopened moisture-proof bags. Once opened, they should be used within a specified time frame or baked according to relevant industry standards (e.g., IPC/JEDEC standards) to remove absorbed moisture before reflow soldering, to prevent \"popcorning\" or delamination.

12. Practical Design and Usage Case

Scenario: Designing a decorative yellow LED string light. A designer needs 50 LEDs per string. To ensure uniform appearance, they specify a tight luminous flux bin (e.g., L7: 16-17 lm) and a single dominant wavelength bin (Y54). They design a driver circuit providing a constant 150 mA. Considering the 50 °C/W thermal resistance, they ensure the PCB has sufficient copper area under the LED pads to act as a heat spreader, especially if the lights will be used in enclosed fixtures. They calculate the total voltage drop for the series string based on the maximum V_F bin (e.g., Bin 34: 2.8V) to size the power supply appropriately. The wide 120-degree viewing angle is perfect for creating a diffuse, glowing effect without hotspots.

13. Operational Principle

Light is generated through electroluminescence. When a forward voltage exceeding the diode's built-in potential is applied, electrons and holes are injected into the active region of the semiconductor chip (composed of AlGaInP). These charge carriers recombine, releasing energy in the form of photons. The specific composition of the AlGaInP alloy determines the bandgap energy, which in turn defines the wavelength (color) of the emitted light—in this case, yellow (590-600 nm). The water-clear resin encapsulation protects the chip, provides mechanical stability, and shapes the light output pattern.

14. Industry Trends and Context

Mid-power LEDs in packages like PLCC-2 have become the workhorse for general lighting applications due to their excellent balance of cost, efficacy (lumens per watt), and reliability. The trend in this segment is towards ever-higher efficacy, allowing for lower energy consumption or higher light output from the same form factor. There is also a continuous drive for improved color consistency (tighter binning) and higher maximum operating temperature ratings. Furthermore, compliance with evolving environmental regulations (RoHS, REACH, halogen-free) is now a standard requirement, not a differentiator. The technology is mature, with focus on manufacturing optimization and integration into smarter, connected lighting systems.