SMD Top View Blue LED 67-21 Series Datasheet - P-LCC-2 Package - 2.7-3.5V - 25mA - 90mW - English Technical Document

1. Product Overview

The 67-21 series represents a family of surface-mount device (SMD) light-emitting diodes (LEDs) designed for top-view applications. This component is engineered to provide reliable indicator and backlighting functionality in a compact, white P-LCC-2 package with a colorless clear window. Its primary design goal is to offer optimized light output and coupling efficiency, making it particularly suitable for integration with light pipes. The device operates at low current levels, which is a critical advantage for battery-powered or power-sensitive portable electronic equipment where energy efficiency is paramount.

The core advantages of this LED include its wide viewing angle, which ensures visibility from various perspectives, and its compatibility with standard automated assembly processes. It is supplied on tape and reel for high-volume production efficiency. The product adheres to several key environmental and safety standards, including being Pb-free, compliant with the EU REACH regulation, and meeting halogen-free requirements (Br<900ppm, Cl<900ppm, Br+Cl<1500ppm). It is also preconditioned based on the JEDEC J-STD-020D Level 3 standard for moisture sensitivity.

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

The Absolute Maximum Ratings define the limits beyond which permanent damage to the device may occur. These are not operating conditions. For the 67-21 series LED, the maximum reverse voltage (VR) is 5V. Exceeding this voltage in the reverse direction can cause junction breakdown. The maximum continuous forward current (IF) is 25 mA. For pulsed operation, a peak forward current (IFP) of 100 mA is allowed under a duty cycle of 1/10 at 1 kHz. The maximum power dissipation (Pd) the package can handle is 90 mW, which is directly related to thermal management. The maximum allowable junction temperature (Tj) is 115°C. The device is rated for operation (Topr) between -40°C and +85°C and for storage (Tstg) between -40°C and +90°C. It can withstand an electrostatic discharge (ESD) of 2000V (Human Body Model). The soldering temperature profile is specified for both reflow (260°C max for 10 seconds) and hand soldering (350°C max for 3 seconds).

2.2 Electro-Optical Characteristics

The Electro-Optical Characteristics are measured at a standard test condition of Ta=25°C and IF=20mA, providing the typical performance parameters. The luminous intensity (Iv) has a typical range from a minimum of 72 mcd to a maximum of 180 mcd, with specific values determined by the bin code. The viewing angle (2θ1/2), defined as the angle where luminous intensity drops to half of its peak value, is typically 120 degrees, offering a very broad emission pattern. The light emitted is blue, with a peak wavelength (λp) typically around 468 nm. The dominant wavelength (λd) ranges from 462 nm to 472 nm. The spectral bandwidth (Δλ) is typically 20 nm. The forward voltage (VF) required to drive 20mA through the LED ranges from 2.70V to 3.50V. The reverse current (IR) is very low, with a maximum of 10 μA when a 5V reverse bias is applied.

3. Bin System Explanation

The performance of LEDs can vary from batch to batch. To ensure consistency for designers, the 67-21 series is categorized into bins for key parameters: luminous intensity, dominant wavelength, and forward voltage.

3.1 Luminous Intensity Bin

Luminous intensity is binned into four codes: Q1 (72-90 mcd), Q2 (90-112 mcd), R1 (112-140 mcd), and R2 (140-180 mcd). A tolerance of ±11% applies. This allows selection based on required brightness levels.

3.2 Dominant Wavelength Bin

The dominant wavelength, which defines the perceived color, is grouped under 'FA' and binned into five codes: AA0 (462.0-464.0 nm), AA1 (464.0-466.0 nm), AA2 (466.0-468.0 nm), AA3 (468.0-470.0 nm), and AA4 (470.0-472.0 nm). A tolerance of ±1nm is specified. This enables precise color matching in applications.

3.3 Forward Voltage Bin

Forward voltage is grouped under 'F' and binned into four codes: 10 (2.70-2.90V), 11 (2.90-3.10V), 12 (3.10-3.30V), and 13 (3.30-3.50V). A tolerance of ±0.1V applies. Knowing the VF bin helps in designing efficient current-limiting circuits and predicting power consumption.

4. Performance Curve Analysis

The datasheet provides several typical characteristic curves that illustrate the device's behavior under varying conditions. These graphs are for reference and represent typical data, not guaranteed minimums or maximums.

Forward Current vs. Forward Voltage (IV Curve): This curve shows the exponential relationship between the current flowing through the LED and the voltage across it. It is crucial for determining the operating point and designing the driver circuit. The curve typically shows that a small increase in voltage beyond the turn-on point results in a large increase in current.

Relative Luminous Intensity vs. Forward Current: This graph demonstrates how light output increases with forward current. It is generally linear within the recommended operating range but may saturate at higher currents. It helps in selecting the drive current for a desired brightness level.

Relative Luminous Intensity vs. Ambient Temperature: This curve shows the derating of light output as the ambient temperature increases. LED efficiency decreases with rising temperature. This is a critical consideration for thermal management in the application to maintain consistent brightness.

Forward Current Derating Curve: This graph indicates the maximum allowable continuous forward current as a function of ambient temperature. As temperature rises, the maximum current must be reduced to prevent exceeding the maximum junction temperature and ensure long-term reliability.

Spectrum Distribution: This plot displays the relative intensity of light emitted across different wavelengths, centered around the peak wavelength of ~468 nm. It shows the spectral purity and width of the blue light emission.

Radiation Diagram: This polar plot visually represents the spatial distribution of light intensity, confirming the wide 120-degree viewing angle. It shows how light is emitted more intensely in the forward direction (0°) and decreases towards the sides.

5. Mechanical and Package Information

The LED is housed in a P-LCC-2 (Plastic Leaded Chip Carrier) package. The package body is white with a colorless clear lens. A detailed dimensioned drawing is provided in the datasheet, specifying the length, width, height, lead spacing, and other critical mechanical features. All tolerances are typically ±0.1mm unless otherwise noted. The drawing includes the top view, side view, and footprint recommendation for PCB layout, showing the anode and cathode pad geometry and the recommended solder mask opening. The polarity is indicated on the device itself, typically by a marking such as a notch or a dot near the cathode.

6. Soldering and Assembly Guidelines

Proper handling and soldering are essential for reliability.

Storage: The components are packaged in moisture-resistant bags with a desiccant and humidity indicator card. The bag should only be opened immediately before use in an environment controlled to less than 30°C and 60% relative humidity. After opening, the components must be used within the timeframe specified by the Moisture Sensitivity Level (MSL 3, based on J-STD-020D). If the indicator card shows excessive moisture, baking at 60°C ±5°C for 24 hours is required before use.

Reflow Soldering: A specific temperature profile for Pb-free solder is recommended. The profile includes a pre-heat stage (150-200°C for 60-120s), a ramp-up to the peak temperature (max 260°C), a time above liquidus (217°C for 60-150s), and a controlled cool-down. The time above 255°C should not exceed 30 seconds, and the peak temperature of 260°C should be held for a maximum of 10 seconds. Reflow should not be performed more than twice. Stress should not be applied to the LED during heating, and the PCB should not be warped after soldering.

Hand Soldering: If necessary, hand soldering should be done with an iron tip temperature below 350°C for no more than 3 seconds per terminal. The soldering iron power should be 25W or less. A minimum interval of 2 seconds should be left between soldering each terminal. A double-head soldering iron is recommended for any repair work to avoid thermal stress.

7. Packaging and Ordering Information

The LEDs are supplied on 8mm carrier tape wound onto reels for automated pick-and-place assembly. Each reel contains 2000 pieces. The reel and tape dimensions are specified in the datasheet. A label on the reel provides key information: Customer's Product Number (CPN), Product Number (P/N), Packing Quantity (QTY), and the bin codes for Luminous Intensity Rank (CAT), Dominant Wavelength Rank (HUE), and Forward Voltage Rank (REF), along with the Lot Number (LOT No).

8. Application Recommendations

Typical Applications: This LED is ideal for telecommunication equipment (indicators and backlights in phones, fax machines), flat backlighting for LCDs, switches, and symbols, light pipe applications for guiding light to a panel or bezel, and general-purpose indicator use.

Design Considerations: Current Limiting: An external current-limiting resistor is mandatory. LEDs are current-driven devices, and a small change in forward voltage can cause a large, potentially destructive change in current. The resistor value can be calculated using Ohm's Law: R = (Vsupply - VF) / IF, where VF is the forward voltage from the bin or typical value, and IF is the desired operating current (e.g., 20mA). Thermal Management: While the power dissipation is low, ensuring adequate PCB copper area or thermal vias can help dissipate heat, especially in high ambient temperature environments or when driven at higher currents. This maintains luminous output and longevity. Optical Design: The wide 120° viewing angle and clear lens make it excellent for light pipe applications where light needs to be extracted and directed. The white package helps reflect internal light, improving overall efficiency.

9. Technical Comparison and Differentiation

Compared to generic blue LEDs, the 67-21 series offers several distinct advantages. The wide 120-degree viewing angle is superior to many standard LEDs which may have narrower beams (e.g., 60-80 degrees), making it better for applications requiring off-axis visibility. The defined binning structure for intensity, wavelength, and voltage provides manufacturers with predictable and consistent performance, which is critical for color matching and brightness uniformity in multi-LED arrays. The package is specifically designed for optimized light coupling, enhancing efficiency when used with light guides. Furthermore, its full compliance with modern environmental standards (RoHS, REACH, Halogen-Free) makes it suitable for global markets with strict regulations.

10. Frequently Asked Questions (FAQs)

Q: Why is a current-limiting resistor absolutely necessary?

A: The LED's IV characteristic is exponential. Without a resistor, the current is only limited by the power supply's capability and the LED's small internal resistance, which can instantly drive the current far beyond the 25mA maximum, causing overheating and catastrophic failure.

Q: Can I drive this LED with a 3.3V supply without a resistor?

A: No. Even if the typical VF is 3.0V, variations due to binning, temperature, and manufacturing tolerances mean the actual VF could be lower. A 3.3V supply connected directly could force excessive current through the LED. Always use a series resistor.

Q: What does the 'Precondition: JEDEC J-STD-020D Level 3' mean?

A: It means the components have a Moisture Sensitivity Level (MSL) of 3. After the factory-sealed moisture barrier bag is opened, the components must be mounted onto a PCB within 168 hours (7 days) when stored at <30°C/60% RH. If this timeframe is exceeded, they must be rebaked before use to prevent 'popcorning' during reflow soldering.

Q: How do I interpret the bin codes on the reel label?

A: The CAT code (e.g., R1) tells you the luminous intensity range. The HUE code (e.g., AA2) tells you the dominant wavelength range. The REF code (e.g., 11) tells you the forward voltage range. This allows you to verify the electrical and optical parameters of the batch you are using.

11. Practical Use Case

Scenario: Designing a status indicator panel for a portable medical device.

The device has multiple status LEDs (Power, Battery Low, Bluetooth Connected) behind a dark tinted polycarbonate window. The 67-21 series is selected. Its wide viewing angle ensures the indicators are visible even when the device is viewed from an angle. The low current requirement (20mA) is ideal for maximizing battery life. A light pipe is designed to channel light from the LED, mounted on the main PCB, up to the front panel window. The white LED package helps reflect light into the pipe. The designer selects LEDs from the same intensity and wavelength bins (e.g., R1, AA2) to ensure all indicators have identical brightness and color. A simple driver circuit with a current-limiting resistor for each LED, calculated for a 3.3V system supply, is implemented. The reflow profile from the datasheet is programmed into the SMT assembly line.

12. Operating Principle

This is a semiconductor diode based on InGaN (Indium Gallium Nitride) chip material. When a forward voltage exceeding the diode's turn-on voltage (approximately 2.7-3.5V) is applied, electrons and holes are injected into the active region of the semiconductor. When these charge carriers recombine, energy is released in the form of photons (light). The specific composition of the InGaN material determines the bandgap energy, which in turn defines the wavelength (color) of the emitted light—in this case, blue light around 468 nm. The P-LCC-2 package encapsulates the chip, provides mechanical protection, houses the wire bonds, and incorporates a lens that shapes the light output beam.

13. Technology Trends

The development of blue LEDs, particularly efficient ones based on InGaN, was a foundational achievement in solid-state lighting, enabling white LEDs (via phosphor conversion) and full-color displays. Current trends in indicator-type SMD LEDs like the 67-21 series focus on several areas: Increased Efficiency: Ongoing material science improvements aim to produce more light (higher luminous efficacy) per unit of electrical input power, further reducing energy consumption. Miniaturization: While the P-LCC-2 is a standard package, there is a constant push for smaller footprints (e.g., 0402, 0201 metric sizes) to save PCB space in ever-shrinking consumer electronics. Enhanced Reliability and Robustness: Improvements in packaging materials and die attach technologies continue to extend operational lifetime and increase resistance to thermal cycling and humidity. Tighter Binning and Color Consistency: As applications demand more precise and uniform lighting, manufacturers implement more stringent and finer binning processes for luminous flux, chromaticity coordinates, and forward voltage.