Mini Top View LED 65-21 Series Datasheet - SMT Package - 2.35V Max - Brilliant Yellow Green - 60mW - English Technical Document

1. Product Overview

The 65-21 series represents a family of Mini Top View Light Emitting Diodes (LEDs) designed for surface-mount technology (SMT) applications. This specific variant, identified by the part number suffix indicating its binning, emits a brilliant yellow-green light. The core design philosophy centers on a top-down mounting configuration where light is emitted through the printed circuit board (PCB). This unique architecture, combined with an integrated inter-reflector, is engineered to optimize light output coupling, making these components exceptionally suitable for applications utilizing light pipes or light guides.

The package is a compact, white surface-mount device. A key performance feature is its exceptionally wide viewing angle, which is characterized as 120 degrees (full width at half maximum, 2θ1/2). This broad emission profile ensures high visibility from various angles, a critical factor for indicator applications. The product is compliant with major environmental and safety directives, including RoHS (Restriction of Hazardous Substances), EU REACH regulations, and is manufactured as halogen-free (with Bromine <900ppm, Chlorine <900ppm, and their sum <1500ppm). It is supplied on tape and reel for compatibility with automated pick-and-place assembly processes.

1.1 Core Advantages and Target Market

The primary advantages of the 65-21 series stem from its mechanical and optical design. The top-view, through-PCB emission is its defining characteristic, enabling efficient coupling into light pipes without requiring side-firing or right-angle mounting. The integrated reflector within the package enhances light extraction and directionality. The wide 120-degree viewing angle provides excellent omnidirectional visibility. The SMT package allows for high-density PCB layouts and is compatible with standard reflow soldering processes.

The target applications are diverse, focusing on areas where compact size, reliable indication, and efficient light guiding are paramount. These include: optical status indicators on consumer electronics and industrial equipment; backlighting for liquid crystal displays (LCDs), keypads, switches, and instrument panels; general illumination for advertising and signage; and interior automotive lighting, such as dashboard backlighting. The component is preconditioned based on JEDEC J-STD-020D Level 3 standards, indicating its robustness for typical commercial soldering processes.

2. Technical Parameter Analysis

This section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters defined in the datasheet. Understanding these limits and characteristics is essential for reliable circuit design and ensuring long-term LED performance.

2.1 Absolute Maximum Ratings

The Absolute Maximum Ratings define the stress limits beyond which permanent damage to the LED may occur. These are not conditions for normal operation.

• Reverse Voltage (V_R): 12V. Exceeding this voltage in the reverse-biased direction can cause junction breakdown.
• Continuous Forward Current (I_F): 25mA. This is the maximum DC current that can be applied continuously.
• Peak Forward Current (I_FP): 60mA. This is allowed only under pulsed conditions (duty cycle of 10% at 1kHz) and must not be used for DC operation.
• Power Dissipation (P_d): 60mW. The maximum power the package can dissipate as heat, calculated as Forward Voltage (V_F) × Forward Current (I_F).
• Junction Temperature (T_j): 115°C. The maximum allowable temperature of the semiconductor chip itself.
• Operating & Storage Temperature: -40°C to +85°C (operating), -40°C to +90°C (storage).
• Electrostatic Discharge (ESD): 2000V (Human Body Model). Proper ESD handling procedures are required.
• Soldering Temperature: For reflow, a peak of 260°C for a maximum of 10 seconds is specified. For hand soldering, 350°C for a maximum of 3 seconds per terminal is allowed.

2.2 Electro-Optical Characteristics

These parameters are measured at a standard test condition of 25°C ambient temperature and a forward current (I_F) of 20mA, unless otherwise noted.

• Luminous Intensity (I_V): Ranges from a minimum of 36 millicandelas (mcd) to a maximum of 90 mcd. The typical value is not specified, as the parts are binned. A tolerance of ±11% applies.
• Viewing Angle (2θ_1/2): 120 degrees. This is the angular width where luminous intensity is at least half of the peak intensity measured at 0 degrees (on-axis).
• Peak Wavelength (λ_p): Approximately 575 nanometers (nm). This is the wavelength at which the spectral power distribution is maximum.
• Dominant Wavelength (λ_d): Ranges from 569.5 nm to 577.5 nm. This is the single-wavelength perception of the LED's color by the human eye and is the key parameter for color binning. Tolerance is ±1nm.
• Spectral Bandwidth (Δλ): Approximately 20 nm. This indicates the spectral purity; a smaller bandwidth means a more monochromatic color.
• Forward Voltage (V_F): Ranges from 1.75V to 2.35V at 20mA. Tolerance is ±0.1V. This is critical for designing the current-limiting resistor in series with the LED.
• Reverse Current (I_R): Maximum of 10 microamperes (μA) when a reverse bias of 12V is applied.

2.3 Thermal Characteristics

While not explicitly listed in a separate table, thermal management is implied through the Power Dissipation (P_d) and Junction Temperature (T_j) ratings. The forward current derating curve graphically shows how the maximum allowable continuous forward current must be reduced as the ambient temperature increases above 25°C to prevent exceeding the 115°C junction temperature limit. Effective PCB layout with adequate thermal relief is necessary for high-current or high-ambient-temperature applications.

3. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins. The 65-21 series uses separate bins for luminous intensity and dominant wavelength.

3.1 Luminous Intensity Binning

Luminous intensity is sorted into four distinct bins (N2, P1, P2, Q1) when measured at I_F = 20mA. Each bin covers a specific range:
- N2: 36 mcd to 45 mcd
- P1: 45 mcd to 57 mcd
- P2: 57 mcd to 72 mcd
- Q1: 72 mcd to 90 mcd
The part number (e.g., G6C-AN2Q1/3T) includes codes that specify which intensity and wavelength bins the device belongs to, allowing designers to select parts with tight performance tolerances for their application.

3.2 Dominant Wavelength Binning

The dominant wavelength, which defines the perceived yellow-green color, is binned within Group A. It is divided into four codes (C16 to C19), each spanning a 2nm range:
- C16: 569.5 nm to 571.5 nm
- C17: 571.5 nm to 573.5 nm
- C18: 573.5 nm to 575.5 nm
- C19: 575.5 nm to 577.5 nm
This precise binning ensures minimal color variation between LEDs in a single assembly, which is crucial for applications like multi-LED backlighting or indicator arrays.

4. Performance Curve Analysis

The datasheet provides several characteristic curves that illustrate the LED's behavior under varying conditions. These are essential for advanced design considerations.

4.1 Relative Luminous Intensity vs. Forward Current

This curve shows that luminous intensity is not linearly proportional to forward current. While intensity increases with current, the relationship tends to sub-linear at higher currents due to increased junction temperature and efficiency droop. Operating significantly above the recommended 20mA test current may yield diminishing returns in brightness and accelerate aging.

4.2 Relative Luminous Intensity vs. Ambient Temperature

This graph demonstrates the negative temperature coefficient of luminous output. As the ambient temperature rises, the LED's light output decreases. This is a fundamental characteristic of semiconductor light sources. The curve allows designers to estimate the brightness loss in high-temperature environments and compensate if necessary.

4.3 Forward Current vs. Forward Voltage (I-V Curve)

The I-V curve is exponential in nature, typical of a diode. A small increase in forward voltage results in a large increase in forward current. This highlights the critical importance of using a current-limiting device (almost always a resistor) in series with the LED when powered by a voltage source. Driving the LED with a constant voltage will lead to thermal runaway and destruction.

4.4 Spectrum Distribution

The spectral distribution plot shows the relative optical power emitted across wavelengths. For this brilliant yellow-green LED, the peak is around 575nm with a typical full width at half maximum (FWHM) of 20nm. This plot is useful for applications sensitive to specific spectral content.

4.5 Radiation Pattern

The polar radiation diagram visually confirms the wide 120-degree viewing angle. The pattern is likely Lambertian or near-Lambertian, meaning intensity is roughly proportional to the cosine of the viewing angle. This pattern is ideal for wide-area illumination and light pipe coupling.

5. Mechanical and Packaging Information

5.1 Package Dimensions and Land Pattern

The datasheet includes a detailed dimensional drawing of the LED package. Key dimensions include the overall length, width, and height, as well as the lead (terminal) spacing and size. A recommended solder pad layout (land pattern) for the PCB is also provided. Adhering to this recommended pattern is crucial for achieving a reliable solder joint, ensuring proper alignment during reflow, and managing thermal stress. The drawing specifies that tolerances are ±0.1mm unless otherwise noted.

5.2 Polarity Identification

Polarity must be observed for correct operation. The datasheet drawing indicates the anode and cathode terminals. Typically, the cathode may be identified by a marking on the package body, such as a dot, notch, or green marking, or by a different lead shape (e.g., shorter lead). Incorrect polarity connection during soldering will prevent the LED from illuminating when forward biased.

6. Soldering and Assembly Guidelines

Proper handling and soldering are critical to prevent damage to these SMT components.

6.1 Reflow Soldering Profile

A specific lead-free (Pb-free) reflow temperature profile is provided. It typically includes: a pre-heating ramp (e.g., 150-200°C for 60-120s), a controlled ramp to peak temperature, a time above liquidus (e.g., above 217°C for 60-150s), a peak temperature not exceeding 260°C for a maximum of 10 seconds, and a controlled cooling phase. The profile emphasizes minimizing thermal shock and exposure to extreme temperatures.

6.2 Critical Precautions

• Current Limiting: An external series resistor is mandatory. Without it, even a small increase in supply voltage can cause a large, destructive increase in current.
• Reflow Cycles: The LED should not undergo reflow soldering more than two times to avoid excessive thermal stress on the package and wire bonds.
• Mechanical Stress: Avoid applying physical stress to the LED during heating (soldering) or by warping the PCB after assembly.
• Hand Soldering: If necessary, use a soldering iron with a tip temperature <350°C, apply heat to each terminal for ≤3 seconds, and allow a cooling interval of ≥2 seconds between terminals. Use a low-power iron (≤25W).
• Repair: Repair after soldering is discouraged. If unavoidable, a specialized double-head soldering iron should be used to simultaneously heat both terminals, preventing mechanical stress from lifting one pad.

7. Packaging and Ordering Information

7.1 Moisture Sensitivity and Storage

The components are packaged in a moisture-resistant barrier bag with a desiccant and a humidity indicator card. The bag should only be opened immediately before use in an environment controlled to <30°C and <60% Relative Humidity. If the indicator card shows excessive moisture exposure, the components must be baked at 60°C ±5°C for 24 hours before use to remove absorbed moisture and prevent \"popcorning\" during reflow.

7.2 Tape and Reel Specifications

The LEDs are supplied on carrier tape wound onto reels for automated assembly. Key specifications include: reel dimensions (diameter, width, hub size), carrier tape pocket dimensions, and pitch (distance between pockets). The standard loaded quantity is 3000 pieces per reel. Detailed drawings for the reel, carrier tape, and the moisture-proof bag packing process are provided in the datasheet.

7.3 Label Explanation

The reel label contains several codes:
- P/N: The full product number.
- CAT: The luminous intensity bin code (e.g., Q1).
- HUE: The dominant wavelength bin code (e.g., C18).
- REF: The forward voltage rank.
- LOT No: Traceability lot number.

8. Application Design Considerations

8.1 Typical Application Circuits

The most basic and essential circuit is a voltage source (V_CC), a current-limiting resistor (R_S), and the LED in series. The resistor value is calculated using Ohm's Law: R_S = (V_CC - V_F) / I_F, where V_F and I_F are the desired operating points. Always use the maximum V_F from the datasheet (2.35V) for a worst-case design to ensure the current does not exceed limits. For example, with a 5V supply and a target I_F of 20mA: R_S = (5V - 2.35V) / 0.020A = 132.5Ω. A standard 130Ω or 150Ω resistor would be appropriate, with power rating P = I_F² × R_S.

8.2 Light Pipe and Guide Coupling

For light pipe applications, the top-view emission through the PCB is ideal. The LED should be positioned directly under the input surface of the light pipe. The wide viewing angle helps capture a large portion of the emitted light into the pipe. The gap between the LED dome and the light pipe should be minimized, and optical coupling materials (e.g., silicone, clear adhesive) may be used to reduce Fresnel reflection losses at the air gap.

8.3 Thermal Management in PCB Layout

Although a small-signal device, thermal management improves longevity. Use the recommended solder pad dimensions. Connecting the thermal pad (if present) or the cathode/anode pads to larger copper areas on the PCB helps dissipate heat. Thermal vias under the package can transfer heat to inner or bottom layers. Avoid placing the LED near other heat-generating components.

9. Technical Comparison and Differentiation

The 65-21 series differentiates itself primarily through its top-view, through-PCB optical path. Compared to standard side-view or right-angle LEDs, this design simplifies mechanical integration with light pipes, eliminating the need for complex bends or 90-degree turns in the light guide. The integrated inter-reflector is a feature aimed at improving optical efficiency specifically for this coupling method. The 120-degree viewing angle is exceptionally wide for a top-view package, offering better off-axis visibility than many competitors. Its compliance with the latest halogen-free and high-temperature (lead-free) soldering standards makes it suitable for modern, environmentally conscious electronics manufacturing.

10. Frequently Asked Questions (FAQ)

Q1: Can I drive this LED directly from a 3.3V or 5V microcontroller pin?
A: No. You must always use a series current-limiting resistor. The I-V curve shows that a small change in voltage causes a large change in current. A microcontroller pin's output voltage can vary, and connecting the LED directly would likely destroy it.

Q2: Why is my LED dimmer than expected when I use it in a high-temperature environment?
A: This is normal behavior. Refer to the \"Relative Luminous Intensity vs. Ambient Temperature\" curve. LED light output decreases as temperature increases. You may need to select a higher brightness bin (e.g., Q1) or slightly increase the drive current (within absolute limits) to compensate, while ensuring thermal limits are not exceeded.

Q3: The bag was opened yesterday. Can I use the remaining LEDs today without baking?
A: It depends on the factory floor conditions and the moisture sensitivity level (MSL) of the component, which is implied by the baking instructions. If the environment was controlled (<30°C/60% RH) and the exposure time was short (likely less than the specified MSL floor life, e.g., 168 hours for MSL 3), it is probably safe. If in doubt, or if the humidity indicator card shows warning levels, bake the components as specified.

Q4: What is the difference between Peak Wavelength and Dominant Wavelength?
A: Peak Wavelength (λ_p) is the physical wavelength where the LED emits the most optical power. Dominant Wavelength (λ_d) is a calculated single wavelength that would be perceived by the human eye as having the same color as the LED's broad spectrum. λ_d is more relevant for color matching in visual applications.

11. Design-in Case Study

Scenario: Designing a status indicator panel with a light pipe for an industrial controller.
1. Requirement: Multiple yellow-green status LEDs need to be visible from the front panel via individual light pipes.
2. Component Selection: The 65-21 series is chosen for its top-view emission, simplifying the mechanical design. The light pipe can be a straight, vertical element sitting directly over the LED on the PCB.
3. Binning: To ensure uniform brightness across the panel, LEDs from the same luminous intensity bin (e.g., all P2 or Q1) are specified. To ensure uniform color, LEDs from the same dominant wavelength bin (e.g., all C18) are specified.
4. Circuit Design: A common 5V rail is used. Using the max V_F of 2.35V and a target I_F of 20mA, a 150Ω series resistor is chosen for each LED, dissipating 60mW (0.06W) per resistor. A 1/8W or 1/10W resistor is sufficient.
5. PCB Layout: LEDs are placed according to the light pipe positions. The recommended land pattern is used. Small thermal relief connections are used on the pads to aid soldering while maintaining some thermal conduction to the ground/power plane.
6. Result: A clean, reliable indicator system with consistent brightness and color, enabled by the specific optical coupling advantages of the 65-21 LED.

12. Operating Principle

The LED is based on an AlGaInP (Aluminum Gallium Indium Phosphide) semiconductor chip. When a forward voltage exceeding the diode's turn-on voltage (approximately 1.8-2.0V) is applied, electrons and holes are injected into the active region of the semiconductor. These charge carriers recombine, releasing energy in the form of photons (light). The specific composition of the AlGaInP alloy determines the bandgap energy, which in turn dictates the wavelength of the emitted light, in this case, in the yellow-green spectrum (around 575nm). The chip is encapsulated in a white, reflective plastic package with a clear epoxy dome. The white plastic reflects side-emitted light upward, and the dome acts as a lens, shaping the radiation pattern and providing environmental protection.

13. Technology Trends

The general trend in indicator and backlight LEDs is toward higher efficiency (more lumens per watt), smaller package sizes enabling higher density, and improved reliability under harsh conditions (higher temperature, humidity). There is also a strong drive for broader adoption of environmentally friendly materials (halogen-free, lead-free) and processes. The specific top-view, through-PCB design exemplified by the 65-21 series addresses a persistent need in human-machine interface (HMI) design for efficient light guiding, a trend that continues as devices become more compact and integrated. Future developments may include even thinner packages, integrated driver circuitry, or tunable color options within a single package footprint.