SMD LED Yellow AlInGaP Datasheet - SMD Package - Forward Voltage 1.8-2.4V - Luminous Flux up to 2.13lm - English Technical Document

1. Product Overview

This document details the specifications for a surface-mount device (SMD) LED utilizing an Aluminum Indium Gallium Phosphide (AlInGaP) semiconductor material to produce yellow light. The device is housed in a water-clear lens package, designed for automated assembly processes and space-constrained applications. Its primary function is to serve as a status indicator, signal luminary, or front-panel backlighting component in a wide array of electronic equipment.

1.1 Core Features and Advantages

• Compliant with RoHS (Restriction of Hazardous Substances) directives.
• Packaged on 8mm tape wound onto 7-inch diameter reels, suitable for high-speed automated pick-and-place equipment.
• Features an EIA (Electronic Industries Alliance) standard package outline.
• IC-compatible logic levels for easy integration with control circuits.
• Fully compatible with infrared (IR) reflow soldering processes, supporting lead-free soldering profiles.
• Preconditioned to accelerate to JEDEC (Joint Electron Device Engineering Council) Moisture Sensitivity Level 3, indicating a floor life of 168 hours at <30°C/60% RH after the bag is opened.

1.2 Target Markets and Applications

This LED is engineered for reliability and performance in diverse sectors. Key application areas include:

• Telecommunications: Status indicators in cordless phones, cellular phones, and network equipment.
• Office Automation: Panel indicators in printers, scanners, and notebook computers.
• Home Appliances: Power-on, mode, or function indicators in various household devices.
• Industrial Equipment: Operational status and fault indicators in control panels and machinery.
• General Indication: Signal and symbol luminary applications, as well as front panel backlighting where uniform illumination is required.

2. In-Depth Technical Parameter Analysis

The following sections provide a detailed breakdown of the device's operational limits and performance characteristics under standard test conditions (Ta=25°C).

2.1 Absolute Maximum Ratings

These values represent the stress limits beyond which permanent damage to the device may occur. Operation at or near these limits is not recommended for extended periods.

• Power Dissipation (Pd): 72 mW. This is the maximum amount of power the device can dissipate as heat.
• Peak Forward Current (I_F(PEAK)): 80 mA. This is the maximum instantaneous forward current, typically specified under pulsed conditions (1/10 duty cycle, 0.1ms pulse width) to prevent overheating.
• Continuous DC Forward Current (I_F): 30 mA. This is the recommended maximum current for continuous operation.
• Reverse Voltage (V_R): 5 V. Applying a reverse voltage exceeding this value can cause junction breakdown.
• Operating Temperature Range: -40°C to +85°C. The ambient temperature range over which the device is designed to function.
• Storage Temperature Range: -40°C to +100°C. The temperature range for non-operational storage.

2.2 Electrical and Optical Characteristics

These parameters define the typical performance of the LED when driven under specified test conditions (I_F = 20mA).

• Luminous Flux (Φ_v): 0.67 lm (Min) to 2.13 lm (Max). This is the total perceived power of light emitted by the source, measured in lumens (lm). The wide range is managed through binning.
• Luminous Intensity (I_v): 224 mcd (Min) to 710 mcd (Max). This is the luminous flux per solid angle in a given direction, measured in millicandelas (mcd). It is a referenced value derived from the luminous flux measurement.
• Viewing Angle (2θ_1/2): 120° (Typical). This is the full angle at which the luminous intensity is half the value at the optical axis (0°), indicating a very wide viewing pattern.
• Peak Emission Wavelength (λ_p): 591 nm (Typical). The wavelength at which the spectral power distribution of the emitted light is maximum.
• Dominant Wavelength (λ_d): 584.5 nm to 594.5 nm. The single wavelength that defines the perceived color of the light, with a tolerance of ±1 nm per bin.
• Spectral Line Half-Width (Δλ): 15 nm (Typical). The spectral width of the emission at half its maximum intensity, indicating color purity.
• Forward Voltage (V_F): 1.8 V (Min) to 2.4 V (Max) at 20mA. The voltage drop across the LED when current is flowing, with a tolerance of ±0.1V per bin.
• Reverse Current (I_R): 10 µA (Max) at V_R=5V. The small leakage current that flows when the device is reverse-biased.

3. Binning System Explanation

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

3.1 Luminous Flux / Intensity Binning

The LED is categorized into bins based on its total light output. The tolerance within each intensity bin is ±11%.

• Bin D2: 0.67 lm to 0.84 lm (224 mcd to 280 mcd)
• Bin E1: 0.84 lm to 1.07 lm (280 mcd to 355 mcd)
• Bin E2: 1.07 lm to 1.35 lm (355 mcd to 450 mcd)
• Bin F1: 1.35 lm to 1.68 lm (450 mcd to 560 mcd)
• Bin F2: 1.68 lm to 2.13 lm (560 mcd to 710 mcd)

3.2 Forward Voltage Binning

LEDs are also sorted by their forward voltage drop at 20mA, with a tolerance of ±0.1V per bin. This is crucial for current-limiting resistor calculation and power supply design.

• Bin D2: 1.8 V to 2.0 V
• Bin D3: 2.0 V to 2.2 V
• Bin D4: 2.2 V to 2.4 V

3.3 Hue / Dominant Wavelength Binning

This binning ensures color consistency. The dominant wavelength, which defines the perceived yellow hue, is sorted into specific ranges with a tolerance of ±1 nm per bin.

• Bin H: 584.5 nm to 587.0 nm
• Bin J: 587.0 nm to 589.5 nm
• Bin K: 589.5 nm to 592.0 nm
• Bin L: 592.0 nm to 594.5 nm

4. Performance Curve Analysis

While specific graphical data is referenced in the datasheet, typical performance trends for AlInGaP LEDs can be analyzed:

4.1 Current vs. Voltage (I-V) Characteristic

The forward voltage (V_F) exhibits a logarithmic relationship with forward current (I_F). It increases non-linearly, with a sharper rise at lower currents (near the turn-on voltage) and a more linear increase at higher currents due to series resistance within the semiconductor and package.

4.2 Luminous Flux vs. Forward Current

The light output (luminous flux) is generally proportional to the forward current over a significant operating range. However, efficiency (lumens per watt) typically peaks at a specific current and may decrease at very high currents due to increased heat generation and efficiency droop.

4.3 Temperature Dependence

Key parameters are affected by junction temperature (T_j):

• Forward Voltage (V_F): Decreases with increasing temperature (negative temperature coefficient).
• Luminous Flux/Intensity: Generally decreases with increasing temperature. The rate of decrease is a critical factor for thermal management in high-power or high-ambient-temperature applications.
• Dominant Wavelength (λ_d): May shift slightly with temperature, affecting the perceived color.

5. Mechanical and Package Information

5.1 Package Dimensions

The device conforms to an EIA standard SMD package outline. All critical dimensions, including body length, width, height, and lead spacing, are provided in the datasheet with a standard tolerance of ±0.2 mm unless otherwise specified. The water-clear lens material is typically epoxy or silicone-based.

5.2 Polarity Identification and Pad Design

The cathode is typically marked on the device body, often with a notch, green dot, or other visual indicator. The datasheet includes a recommended printed circuit board (PCB) land pattern (attachment pad) for infrared or vapor phase reflow soldering. This pattern is designed to ensure proper solder joint formation, self-alignment during reflow, and reliable mechanical attachment.

6. Soldering and Assembly Guidelines

6.1 Recommended IR Reflow Profile

The device is compatible with lead-free (Pb-free) soldering processes. The datasheet references a profile compliant with J-STD-020B. Key parameters typically include:

• Pre-heat: 150°C to 200°C, with a maximum time of 120 seconds to gradually heat the assembly and activate the flux.
• Peak Temperature: Maximum of 260°C. The time above the liquidus temperature of the solder (e.g., 217°C for SAC305) must be controlled.
• Total Soldering Time: Maximum of 10 seconds at peak temperature, with a maximum of two reflow cycles allowed.

Note: The optimal profile depends on the specific PCB design, components, solder paste, and oven. The provided profile is a guideline that must be characterized for the actual production setup.

6.2 Hand Soldering

If hand soldering is necessary, extreme care must be taken:

• Iron Temperature: Maximum 300°C.
• Soldering Time: Maximum 3 seconds per joint.
• Limit: Only one soldering cycle is permitted for hand soldering to minimize thermal stress on the LED package.

6.3 Cleaning

Only specified cleaning agents should be used. Unspecified chemicals may damage the epoxy lens or package. If cleaning is required post-soldering, immersion in ethyl alcohol or isopropyl alcohol at room temperature for less than one minute is recommended.

6.4 Storage and Handling

Proper storage is critical due to the device's moisture sensitivity level (MSL 3):

• Sealed Package: Store at ≤30°C and ≤70% Relative Humidity (RH). Use within one year of the bag seal date.
• Opened Package: Store at ≤30°C and ≤60% RH. Components must be IR-reflowed within 168 hours (7 days) of exposure to ambient air.
• Extended Exposure: For storage beyond 168 hours, store in a sealed container with desiccant or in a nitrogen ambient. Components exposed for more than 168 hours require baking at approximately 60°C for at least 48 hours before soldering to remove absorbed moisture and prevent "popcorning" during reflow.

7. Packaging and Ordering Information

7.1 Tape and Reel Specifications

The LEDs are supplied in industry-standard embossed carrier tape:

• Tape Width: 8 mm.
• Reel Diameter: 7 inches.
• Quantity per Reel: 2000 pieces (standard full reel).
• Minimum Order Quantity (MOQ): 500 pieces for remainder quantities.
• The tape is sealed with a top cover tape. The packaging conforms to ANSI/EIA-481 specifications, with allowances for a maximum of two consecutive missing components.

8. Application Notes and Design Considerations

8.1 Current Limiting

A series current-limiting resistor is mandatory for reliable operation. The resistor value (R_s) can be calculated using Ohm's Law: R_s = (V_supply - V_F) / I_F. Use the maximum V_F from the bin or datasheet to ensure the current does not exceed the desired I_F under worst-case conditions. The power rating of the resistor must be sufficient: P_R = (I_F)² * R_s.

8.2 Thermal Management

While this is a low-power device, proper thermal design extends lifetime and maintains light output stability. Ensure adequate copper area on the PCB connected to the LED's thermal pad (if applicable) or leads to dissipate heat. Avoid operating at the absolute maximum current and power dissipation in high ambient temperatures.

8.3 Optical Design

The 120° viewing angle provides a very wide beam. For applications requiring a more focused beam, secondary optics (lenses, light pipes) must be used. The water-clear lens is suitable for applications where the die image is not critical; for a more diffuse appearance, a milky or colored diffused lens would be required.

9. Frequently Asked Questions (FAQ)

9.1 What is the difference between Luminous Flux and Luminous Intensity?

Luminous Flux (lm) measures the total amount of visible light emitted by the source in all directions. Luminous Intensity (mcd) measures how bright the source appears in a specific direction. A high-intensity LED may have a narrow beam, while a high-flux LED emits more total light, potentially over a wider area. In this datasheet, intensity is a referenced value derived from the flux measurement.

9.2 Why is binning important?

Manufacturing variations cause differences in V_F, light output, and color between individual LEDs. Binning sorts them into groups with tightly controlled parameters. For applications requiring uniform appearance (e.g., multi-LED displays, backlights) or precise current drive, specifying a single bin or a mix of bins from the same group is essential.

9.3 Can I drive this LED without a current-limiting resistor?

No. An LED is a diode with a non-linear I-V characteristic. A small increase in voltage above its V_F can cause a large, potentially destructive increase in current. A series resistor (or a constant-current driver) is always required to set the operating point safely.

9.4 What happens if I exceed the storage or reflow time after opening the bag?

Moisture absorbed into the plastic package can vaporize rapidly during the high-temperature reflow soldering process, causing internal delamination, cracking, or bond wire damage ("popcorning"). Following the MSL 3 guidelines (168 hours floor life) and performing the required bake-out if exceeded is critical for assembly yield and long-term reliability.

10. Operational Principle and Technology

10.1 AlInGaP Semiconductor Technology

This LED uses an Aluminum Indium Gallium Phosphide (AlInGaP) semiconductor compound for its active region. By precisely controlling the ratios of these elements during crystal growth, the bandgap of the material is engineered to emit light in the yellow region of the visible spectrum (around 590 nm) when electrons and holes recombine across the bandgap (electroluminescence). AlInGaP technology is known for its high efficiency in the red, orange, and yellow wavelengths.

10.2 SMD Package Construction

The semiconductor die is mounted onto a leadframe, which provides the electrical connections (anode and cathode) and often acts as a heat sink. Bond wires connect the top of the die to the other leadframe terminal. This assembly is then encapsulated in a transparent epoxy or silicone molding compound that forms the lens. The lens shape determines the viewing angle and provides mechanical and environmental protection.