Full Color Top View LED 67-23 Series - Package 3.2x2.8x1.9mm - Forward Voltage 2.0-4.0V - Power 60-130mW - English Technical Document

1. Product Overview

The 67-23 series represents a family of full-color, top-view light-emitting diodes (LEDs) designed for surface-mount applications. These LEDs are characterized by their compact P-LCC-4 (Plastic Leaded Chip Carrier, 4-pin) package with a colorless clear window, providing a wide and uniform light emission pattern. The primary design philosophy centers on achieving optimal performance in backlighting and light guide (light pipe) systems, making them ideal for applications where space and power efficiency are critical.

The core advantages of this series include its exceptionally wide viewing angle, facilitated by the package design and an integrated inter-reflector. This feature ensures consistent luminance over a broad area, which is crucial for indicator and backlight applications. Furthermore, the devices are engineered for low-current operation, with a typical forward current of 20mA and the capability to function down to 2mA. This low power requirement makes them exceptionally suitable for battery-powered portable electronics and other devices where minimizing energy consumption is a priority. The series is available in multiple emitted colors, including deep red, brilliant yellow-green, and blue, allowing for versatile design implementations.

2. Technical Parameter Deep-Dive Analysis

2.1 Electro-Optical Characteristics

The performance of each LED color variant is defined by specific electro-optical parameters measured at a standard condition of 25°C ambient temperature and a forward current (I_F) of 20mA.

• Luminous Intensity (I_V): This parameter indicates the perceived brightness of the LED. The Deep-Red (SDR) variant offers the highest typical intensity at 112 mcd (millicandela). The Brilliant Yellow-Green (SYG) and Blue (UB) variants provide typical intensities of 20 mcd and 18 mcd, respectively. Designers must consider these values when determining the required number of LEDs for a given luminance target.
• Wavelength Characteristics: The emitted light color is precisely defined. The Deep-Red LED has a typical peak wavelength (λ_p) of 650 nm and a dominant wavelength (λ_d) of 639 nm. The Yellow-Green LED emits at 575 nm (peak) and 573 nm (dominant). The Blue LED operates at 468 nm (peak) and 470 nm (dominant). The spectral bandwidth (Δλ), which affects color purity, is approximately 20 nm for the red and yellow-green LEDs and 26 nm for the blue LED.
• Viewing Angle (2θ_1/2): A key feature of this series is its 120-degree viewing angle. This wide angle ensures that the LED remains visible from a broad range of perspectives, which is essential for panel indicators and backlighting where the user's viewing position may vary.

2.2 Electrical and Thermal Parameters

Understanding the electrical limits and thermal behavior is crucial for reliable circuit design.

• Forward Voltage (V_F): The voltage drop across the LED when operating. The red and yellow-green LEDs have a typical V_F of 2.0V (max 2.4V), while the blue LED requires a higher typical V_F of 3.5V (max 4.0V). This difference must be accounted for in the driving circuitry, especially in multi-color designs.
• Absolute Maximum Ratings: These are stress limits that must not be exceeded under any conditions to prevent permanent damage. Key limits include a reverse voltage (V_R) of 5V for all colors. The maximum continuous forward current (I_F) is 25mA for red/yellow-green and 30mA for blue. The peak forward current (I_FP) for pulsed operation (1/10 duty cycle at 1kHz) is higher at 60mA for red/yellow-green and 100mA for blue. The maximum power dissipation (P_d) is 60mW for red/yellow-green and 130mW for blue, directly related to thermal management.
• Operating and Storage Temperature: The devices are rated for an operating temperature range (T_opr) of -40°C to +85°C and a storage temperature range (T_stg) of -40°C to +100°C, ensuring functionality in harsh environments.
• Electrostatic Discharge (ESD): The Human Body Model (HBM) ESD tolerance is 2000V for the red and yellow-green LEDs and 1000V for the blue LED. Proper ESD handling procedures are recommended during assembly.

3. Binning System Explanation

The product utilizes a binning system to categorize LEDs based on key performance parameters, ensuring consistency within a production batch. The labeling on the reel indicates three primary bins:

• CAT (Luminous Intensity Rank): This code groups LEDs according to their measured luminous intensity. Designers can select a specific CAT bin to guarantee a minimum brightness level for their application, which is vital for achieving uniform appearance in multi-LED arrays.
• HUE (Dominant Wavelength Rank): This bin categorizes LEDs based on their dominant wavelength, which defines the precise color point. Selecting a tight HUE bin is critical for applications requiring precise color matching, such as status indicators or multi-color displays where color consistency is paramount.
• REF (Forward Voltage Rank): This code sorts LEDs by their forward voltage drop. Using LEDs from the same REF bin can simplify current-limiting resistor design and help ensure uniform current sharing when multiple LEDs are connected in parallel, promoting longevity and consistent brightness.

4. Performance Curve Analysis

While specific graphical data is referenced in the datasheet, the typical electro-optical characteristics curves would generally illustrate the relationship between key parameters. These typically include:

• Relative Luminous Intensity vs. Forward Current (I-V Curve): This curve shows how light output increases with driving current. It is typically non-linear, and operating near the maximum current may offer diminishing returns in brightness while increasing heat and stress on the device.
• Forward Voltage vs. Forward Current: This graph depicts the diode's turn-on characteristic. The voltage increases logarithmically with current after the threshold voltage is reached.
• Luminous Intensity vs. Ambient Temperature: LED light output generally decreases as the junction temperature rises. Understanding this derating is essential for applications operating at high ambient temperatures to ensure the required brightness is maintained.
• Spectral Distribution: A plot of relative intensity versus wavelength, showing the shape and width of the emission spectrum for each color variant.

5. Mechanical and Packaging Information

5.1 Package Dimensions and Layout

The LED is housed in a P-LCC-4 package with overall dimensions of approximately 3.2mm in length, 2.8mm in width, and 1.9mm in height (excluding the dome lens). The package features four leads. A top-view diagram clearly shows the anode and cathode connections for each of the three color chips (Red, Green, Blue) within the single package, which is crucial for correct PCB footprint design and orientation during assembly. The recommended land pattern (solder pad design) is provided to ensure reliable solder joint formation during reflow processes.

5.2 Polarity Identification

The datasheet includes a diagram indicating the polarity of each chip. Correct identification of the anode and cathode for the red, green, and blue diodes is essential to prevent reverse bias during operation, which could damage the LED.

6. Soldering and Assembly Guidelines

These SMD LEDs are compatible with standard automated placement equipment and soldering processes.

• Reflow Soldering: The devices are suitable for vapor-phase and infrared reflow soldering. The maximum recommended soldering temperature profile peaks at 260°C for a duration not exceeding 10 seconds. This profile must be strictly adhered to prevent thermal damage to the plastic package and the internal wire bonds.
• Hand Soldering: If manual soldering is necessary, the iron tip temperature should not exceed 350°C, and contact time should be limited to 3 seconds or less per lead. A heat sink may be used on the lead between the joint and the package body.
• Storage and Handling: The LEDs are shipped in moisture-sensitive packaging. The bag should not be opened until the components are ready for use. Before opening, storage conditions should be 30°C/90%RH or less. After opening, the components have a specified floor life (exposure time to ambient factory conditions) of 168 hours (7 days). If this time is exceeded, a baking procedure may be required prior to reflow to prevent \"popcorning\" or delamination during soldering.

7. Packaging and Ordering Information

The LEDs are supplied on tape and reel for automated assembly. The carrier tape width is 8mm. Each standard reel contains 2000 pieces. The reel label contains critical information including the component part number (CPN), quantity (QTY), lot number (LOT NO), and the specific binning codes (CAT, HUE, REF) for the LEDs on that reel. The moisture-resistant packaging consists of the reel placed inside an aluminum laminate moisture-proof bag along with a desiccant and a humidity indicator card to protect the components during storage and transit.

8. Application Recommendations

8.1 Typical Application Scenarios

• Automotive Interior: Backlighting for dashboard instrument clusters, control switches, and infotainment system buttons.
• Telecommunication Equipment: Status indicators and keypad backlighting in desk phones, mobile devices, and fax machines.
• Consumer Electronics: Backlighting for LCD displays in appliances, flat illumination for symbols on control panels, and general indicator lights.
• Light Pipe/Guide Systems: The wide viewing angle and inter-reflector design make these LEDs exceptionally effective for coupling light into acrylic or polycarbonate light guides, enabling illumination of labels, buttons, or graphic overlays from the edge.

8.2 Design Considerations and Precautions

• Current Limiting: It is mandatory to use an external current-limiting resistor in series with each LED or LED string. The LED's forward voltage has a negative temperature coefficient and a manufacturing tolerance. A slight increase in supply voltage without a series resistor can cause a large, potentially destructive increase in forward current. The resistor value can be calculated using Ohm's Law: R = (V_supply - V_F) / I_F.
• Thermal Management: While the power dissipation is low, ensuring adequate PCB copper area around the thermal pad (if applicable) or leads can help dissipate heat, especially in high ambient temperature environments or when driving at or near maximum current. This helps maintain luminous output and long-term reliability.
• ESD Protection: Implement standard ESD precautions during handling and assembly. Consider adding transient voltage suppression (TVS) diodes or other protection circuits on sensitive lines if the application is in an environment prone to static discharge.

9. Reliability and Quality Assurance

The datasheet outlines a comprehensive set of reliability tests performed to ensure product robustness under various environmental and operational stresses. These tests are conducted with a 90% confidence level and a Lot Tolerance Percent Defective (LTPD) of 10%. Key test items include:

• Reflow Soldering Resistance (260°C)
• Temperature Cycling (-40°C to +100°C)
• Thermal Shock (-10°C to +100°C)
• High-Temperature Storage (100°C)
• Low-Temperature Storage (-40°C)
• DC Operating Life (1000 hours at 20mA)
• High Temperature/High Humidity Storage (85°C/85% RH)

Passing these stringent tests validates the LED's suitability for demanding applications, including automotive and industrial uses.

10. Technical Comparison and Differentiation

The 67-23 series differentiates itself in the market through several key features. Compared to standard top-view LEDs, its integrated inter-reflector and package optics are specifically optimized for light pipe coupling efficiency, reducing optical losses. The ability to operate effectively at very low currents (down to 2mA) is a significant advantage for ultra-low-power designs, a feature not always emphasized in competing products. Furthermore, offering three distinct primary colors in a single, compact P-LCC-4 package provides design flexibility for full-color indicator applications without requiring additional PCB space for separate monochromatic LEDs.

11. Frequently Asked Questions (FAQ)

Q: Can I drive these LEDs without a current-limiting resistor if my power supply is precisely regulated at the LED's typical forward voltage?

A: No. This is strongly discouraged and likely to lead to LED failure. The forward voltage varies with temperature and from unit to unit. Even a small positive deviation in supply voltage can cause excessive current. Always use a series resistor or a dedicated constant-current LED driver.

Q: What is the purpose of the binning codes (CAT, HUE, REF)?

A: Binning ensures electrical and optical consistency. For example, if visual color uniformity is critical in an array, specifying a tight HUE bin is necessary. If brightness consistency is key, specify a CAT bin. Using binned parts prevents noticeable differences between LEDs in the final product.

Q: How do I interpret the \"floor life\" of 168 hours?

A: After the moisture-proof bag is opened, the components absorb moisture from the air. If they are subjected to reflow soldering after absorbing too much moisture (beyond the 168-hour floor life), the rapid heating can cause internal steam pressure, leading to package cracking (\"popcorning\"). If the floor life is exceeded, the components must be baked according to the appropriate IPC/JEDEC standard (e.g., 125°C for 24 hours) to remove moisture before soldering.

12. Design-in Case Study Example

Scenario: Designing a backlit membrane switch panel for a medical device.

Requirements: Uniform white backlighting for multiple buttons, ultra-low power consumption for battery life, and reliable operation.

Implementation: A light guide panel (LGP) made of clear acrylic is designed to sit behind the graphic overlay. Several 67-23 series Blue (UB) and Yellow-Green (SYG) LEDs are placed along the edge of the LGP. The wide 120-degree viewing angle of the LEDs ensures efficient coupling of light into the edge of the acrylic. The light is then scattered uniformly across the button areas by micro-features printed on the LGP. By mixing the blue and yellow-green light in the correct proportion (driven by separate PWM-controlled circuits), a neutral white backlight can be achieved. The low 2mA minimum operating current allows the backlight to be dimmed to very low levels for night-time use, significantly extending battery life. The P-LCC-4 package allows for a compact PCB layout around the edge of the device.

13. Operational Principle

Light-emitting diodes are semiconductor devices that emit light through electroluminescence. When a forward voltage is applied across the p-n junction, electrons from the n-type material recombine with holes from the p-type material in the active region. This recombination process releases energy in the form of photons (light). The specific wavelength (color) of the emitted light is determined by the energy bandgap of the semiconductor materials used in the active region. The 67-23 series utilizes different material systems: AlGaInP for the red and yellow-green chips, and InGaN/SiC for the blue chip. The package lens and internal reflector are then used to shape and direct the emitted light into the desired viewing pattern.

14. Technology Trends and Context

The development of LEDs like the 67-23 series is part of broader trends in optoelectronics. There is a continuous drive towards higher efficiency (more lumens per watt), which allows for either brighter output at the same power or the same output at lower power—both beneficial for portable and energy-conscious applications. Package miniaturization is another key trend, enabling LEDs to be integrated into ever-smaller devices. Furthermore, there is increasing demand for LEDs with precise and consistent color characteristics to meet the needs of advanced display and signaling applications. The emphasis on wide viewing angles and compatibility with light guides reflects the growing importance of sophisticated human-machine interfaces (HMIs) in automotive, industrial, and consumer products, where even and attractive illumination is a key design element.