SMD Middle Power Blue LED 67-21S/B3C Datasheet - PLCC-2 Package - 3.2V Typ - 0.27W Max - English Technical Document

1. Product Overview

The 67-21S/B3C is a surface-mount device (SMD) middle power LED designed for general lighting applications. It utilizes a PLCC-2 (Plastic Leaded Chip Carrier) package, offering a compact form factor suitable for automated assembly processes. The primary emitted color is blue, achieved through InGaN chip technology, with a water-clear resin lens that provides a wide 120-degree viewing angle. This combination of features makes it an efficient and versatile light source.

Key advantages of this LED include its high luminous efficacy, which translates to good light output for its power consumption level. The package is lead-free and compliant with major environmental regulations including RoHS, EU REACH, and halogen-free requirements (Br<900ppm, Cl<900ppm, Br+Cl<1500ppm), ensuring it meets modern manufacturing and sustainability standards.

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

The device's operational limits are defined under specific conditions (soldering point temperature at 25°C). The maximum continuous forward current (I_F) is 75 mA. For pulsed operation, a peak forward current (I_FP) of 150 mA is allowed under a duty cycle of 1/10 and a pulse width of 10 ms. The maximum power dissipation (P_d) is 270 mW. The operating temperature range (T_opr) is from -40°C to +85°C, while storage can occur between -40°C and +100°C. The thermal resistance from the junction to the soldering point (R_{th J-S}) is 50 °C/W, and the maximum allowable junction temperature (T_j) is 115°C. Soldering must adhere to strict profiles: reflow soldering at 260°C for a maximum of 10 seconds, or hand soldering at 350°C for a maximum of 3 seconds. The device is sensitive to electrostatic discharge (ESD), requiring proper handling precautions.

2.2 Electro-Optical Characteristics

Measured at a soldering point temperature of 25°C and a forward current of 60 mA, the key performance parameters are defined. The luminous flux (I_v) has a typical range, with minimum and maximum values specified in the binning section. The forward voltage (V_F) typically falls between 2.9V and 3.6V at 60mA. The viewing angle (2θ_1/2) is 120 degrees, providing a broad emission pattern. The reverse current (I_R) is limited to a maximum of 50 µA at a reverse voltage (V_R) of 5V. Tolerances for luminous flux and forward voltage are ±11% and ±0.1V, respectively.

3. Binning System Explanation

To ensure consistency in application design, LEDs are sorted into bins based on key parameters.

3.1 Luminous Flux Binning

Luminous flux is categorized into bins D5, D6, and D7. Bin D5 covers 2.5 to 3.0 lumens, D6 covers 3.0 to 3.5 lumens, and D7 covers 3.5 to 4.0 lumens, all measured at I_F=60mA.

3.2 Forward Voltage Binning

Forward voltage is finely binned from code 36 to 42. Each bin represents a 0.1V step, starting from 2.9-3.0V (Bin 36) up to 3.5-3.6V (Bin 42), measured at I_F=60mA.

3.3 Dominant Wavelength Binning

The blue color is defined by dominant wavelength bins. Bin B50 covers 445nm to 450nm, and Bin B51 covers 450nm to 455nm, measured at I_F=60mA with a measurement tolerance of ±1nm.

4. Performance Curve Analysis

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

4.1 Spectrum Distribution

A graph shows the relative luminous intensity versus wavelength, typical for a blue InGaN LED, with a peak in the 455-460nm region.

4.2 Forward Voltage vs. Temperature

Figure 1 depicts the forward voltage shift relative to junction temperature. The voltage typically decreases as temperature increases, which is a characteristic of semiconductor diodes.

4.3 Relative Radiometric Power vs. Current

Figure 2 shows that light output increases with forward current but may exhibit sub-linear behavior at higher currents due to efficiency droop and thermal effects.

4.4 Relative Luminous Flux vs. Temperature

Figure 3 illustrates the derating of luminous flux with increasing junction temperature. Light output decreases as temperature rises, highlighting the importance of thermal management.

4.5 IV Characteristic Curve

Figure 4 presents the relationship between forward current and forward voltage at a fixed temperature, showing the typical exponential diode curve.

4.6 Current Derating vs. Temperature

Figure 5 shows the maximum allowable driving forward current as a function of soldering temperature, considering the thermal resistance. This graph is crucial for determining safe operating conditions in different thermal environments.

4.7 Radiation Pattern

Figure 6 is a polar diagram showing 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 PLCC-2 package has a defined footprint and profile. Detailed dimensional drawings are provided, with standard tolerances of ±0.15mm unless otherwise specified. The design includes anode and cathode markings for correct PCB orientation.

5.2 Pad Design and Polarity

The solder pad layout is designed for stable mounting and good solder joint formation. Clear polarity indicators (typically a notch or a marked cathode) on the package and recommended PCB silkscreen ensure correct installation.

6. Soldering and Assembly Guidelines

Strict soldering profiles must be followed to prevent damage. For reflow soldering, the peak temperature must not exceed 260°C for more than 10 seconds. For hand soldering, the iron tip temperature should not exceed 350°C, and contact time should be limited to 3 seconds per pad. The devices are moisture-sensitive and should be stored in their original moisture-resistant packaging. If the exposure time exceeds limits, baking may be required before soldering.

7. Packaging and Ordering Information

The LEDs are supplied on moisture-resistant tape and reel for automated pick-and-place assembly. Standard reel quantities include 250, 500, 1000, 2000, 3000, and 4000 pieces. The reel and carrier tape dimensions are specified with tolerances of ±0.1mm. The packaging process involves sealing the reel in an aluminum moisture-proof bag with desiccant. Labels on the bag and reel provide critical information: Customer's Product Number (CPN), Product Number (P/N), quantity (QTY), and the specific bin codes for luminous intensity (CAT), dominant wavelength (HUE), and forward voltage (REF), along with the lot number (LOT No).

8. Application Suggestions

8.1 Typical Application Scenarios

This LED is suitable for decorative and entertainment lighting, agriculture lighting (e.g., supplemental blue light for plant growth), and general illumination applications where a compact, efficient blue light source is needed.

8.2 Design Considerations

Designers must consider thermal management due to the 50 °C/W thermal resistance. Adequate PCB copper area or heatsinking is necessary to maintain a low junction temperature for optimal performance and longevity. Current limiting is essential; a constant current driver is recommended over a constant voltage source to ensure stable light output and prevent thermal runaway. The binning codes must be reviewed for color and brightness consistency in the final application.

9. Reliability Testing

The product undergoes a comprehensive suite of reliability tests with a 90% confidence level and 10% LTPD (Lot Tolerance Percent Defective). Tests include reflow soldering resistance, thermal shock (-10°C to +100°C), temperature cycling (-40°C to +100°C), high temperature/humidity storage (85°C/85%RH), high temperature/humidity operation, low/high temperature storage, and various high/low temperature operation life tests under different current stresses. These tests validate the LED's robustness under typical environmental and operational stresses.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the typical operating current?

A: The electro-optical characteristics are specified at 60mA, which can be considered a typical operating point. The absolute maximum continuous current is 75mA.

Q: How do I interpret the luminous flux bins?

A> The bin code (D5, D6, D7) on the label indicates the guaranteed minimum and maximum luminous flux range for that specific reel of LEDs, ensuring brightness consistency within your design.

Q: Why is thermal management important?

A> As shown in the performance curves, luminous output decreases and forward voltage shifts with rising junction temperature. Exceeding the maximum junction temperature (115°C) can lead to accelerated degradation or failure. The thermal resistance of 50 °C/W defines how easily heat can escape.

Q: Can I drive this LED with a 3.3V supply?

A> Possibly, but not directly. The forward voltage ranges from 2.9V to 3.6V. A constant 3.3V supply could overdrive LEDs in lower voltage bins or fail to properly turn on LEDs in higher voltage bins. A constant current driver is the recommended method.

11. Design and Usage Case Study

Consider a design for a decorative blue accent light strip. The designer selects the 67-21S/B3C LED for its compact size and wide viewing angle. To ensure uniform color and brightness, they specify a tight binning requirement, e.g., B51 for wavelength and D6 for flux. A constant current driver IC is chosen to provide 60mA per LED. The PCB layout incorporates generous copper pours under the LED pads to act as a heat spreader, connected to larger ground planes to dissipate heat, keeping the estimated junction temperature below 85°C in the application's ambient environment. The tape-and-reel packaging allows for efficient automated assembly of the light strip.

12. Technical Principle Introduction

This LED is based on a semiconductor heterostructure made of Indium Gallium Nitride (InGaN). When a forward voltage is applied, electrons and holes are injected into the active region where they recombine, releasing energy in the form of photons (light). The specific composition of the InGaN alloy determines the bandgap energy, which in turn defines the wavelength of the emitted blue light. The water-clear epoxy resin lens encapsulates the chip, provides mechanical protection, and shapes the light output beam.

13. Technology Trends

The middle-power LED segment continues to evolve towards higher efficacy (more lumens per watt), improved color consistency, and lower cost. Advances in chip design, phosphor technology (for white LEDs), and package materials contribute to these trends. There is also a strong drive for further miniaturization and integration, as well as enhanced reliability under higher drive currents and operating temperatures. The compliance with halogen-free and other environmental standards is now a baseline expectation in the industry.