SMD LED Green Diffused 120° Viewing Angle - 3.2x1.6x1.1mm - 3.3V - 80mW - English Datasheet

1. Product Overview

This document details the specifications for a surface-mount device (SMD) light-emitting diode (LED) utilizing a diffused lens and InGaN (Indium Gallium Nitride) technology to produce green light. Designed for automated printed circuit board (PCB) assembly, this component is ideal for space-constrained applications across various electronic equipment. Its primary function is to serve as a status indicator, signal luminary, or for front panel backlighting in consumer, industrial, and communication devices.

The LED is packaged on 8mm tape wound onto 7-inch diameter reels, facilitating high-speed pick-and-place assembly processes. It is compliant with industry standards, including RoHS (Restriction of Hazardous Substances), and is compatible with infrared (IR) reflow soldering processes, making it suitable for modern, lead-free manufacturing lines.

1.1 Key Features

• RoHS compliant composition.
• Packaged in 8mm tape on 7\" reels for automated assembly.
• Standard EIA package footprint.
• Logic-level compatible (I.C. compatible) drive requirements.
• Designed for compatibility with automatic placement equipment.
• Withstands infrared reflow soldering profiles.
• Preconditioned to JEDEC Moisture Sensitivity Level 3.

1.2 Target Applications

• Telecommunication equipment (e.g., cordless/cellular phones).
• Office automation devices (e.g., notebook computers, network systems).
• Home appliances and indoor signboards.
• Industrial equipment status indicators.
• General-purpose signal and symbol luminaires.
• Front panel backlighting.

2. Package Dimensions and Mechanical Information

The LED conforms to a standard SMD package outline. Critical dimensions include a body size of approximately 3.2mm in length, 1.6mm in width, and 1.1mm in height, with a tolerance of ±0.2mm unless otherwise specified. The component features a diffused lens, which broadens the light emission pattern, and the anode/cathode terminals are clearly designated for correct PCB orientation. The recommended PCB attachment pad layout is provided to ensure optimal solder joint formation and thermal management during reflow soldering processes.

3. In-Depth Technical Parameter Analysis

3.1 Absolute Maximum Ratings

These ratings define the limits beyond which permanent damage to the device may occur. Operation should always be maintained within these boundaries.

• Power Dissipation (Pd): 80 mW. This is the maximum amount of power the device can dissipate as heat at an ambient temperature (Ta) of 25°C.
• Peak Forward Current (I_FP): 100 mA. This is the maximum instantaneous forward current, permissible only under pulsed conditions (1/10 duty cycle, 0.1ms pulse width) to prevent overheating.
• Continuous Forward Current (I_F): 20 mA. This is the recommended maximum DC current for reliable continuous operation.
• Operating Temperature Range: -40°C to +85°C. The device is guaranteed to function within this ambient temperature range.
• Storage Temperature Range: -40°C to +100°C. The device can be stored without degradation within these limits.

3.2 Electrical and Optical Characteristics

These parameters are measured at Ta=25°C and I_F=20mA, representing typical operating conditions.

• Luminous Intensity (I_V): 355 - 1120 mcd (millicandela). The light output is measured using a sensor filtered to match the human eye's photopic response. The wide range is managed through a binning system.
• Viewing Angle (2θ_1/2): 120 degrees (typical). This is the full angle at which the luminous intensity drops to half of its peak axial value. The diffused lens creates this wide, uniform viewing pattern.
• Peak Emission Wavelength (λ_P): 523 nm (typical). This is the wavelength at which the spectral power distribution is maximum.
• Dominant Wavelength (λ_d): 520 - 535 nm. This is the single wavelength perceived by the human eye that defines the color (green) of the LED, derived from the CIE chromaticity diagram.
• Spectral Line Half-Width (Δλ): 25 nm (typical). This indicates the spectral purity; a value of 25nm is characteristic of InGaN-based green LEDs.
• Forward Voltage (V_F): 3.3V (typical), 3.8V (max). The voltage drop across the LED when driven at 20mA.
• Reverse Current (I_R): 10 μA (max) at V_R=5V. The device is not designed for reverse bias operation; this parameter is for test purposes only.

4. Binning System Explanation

To ensure consistency in application, LEDs are sorted (binned) based on key parameters. Designers can specify bins to match their requirements for color and brightness uniformity.

4.1 Forward Voltage (V_f) Rank

Binned at I_F=20mA. Tolerance per bin is ±0.1V.
Example bins: D7 (2.8-3.0V), D8 (3.0-3.2V), D9 (3.2-3.4V), D10 (3.4-3.6V), D11 (3.6-3.8V).

4.2 Luminous Intensity (I_V) Rank

Binned at I_F=20mA. Tolerance per bin is ±11%.
Example bins: T2 (355-450 mcd), U1 (450-560 mcd), U2 (560-710 mcd), V1 (710-900 mcd), V2 (900-1120 mcd).

4.3 Dominant Wavelength (W_d) Rank

Binned at I_F=20mA. Tolerance per bin is ±1nm.
Example bins: AP (520-525 nm), AQ (525-530 nm), AR (530-535 nm).

5. Performance Curve Analysis

Typical characteristic curves provide insight into device behavior under varying conditions. These include the relationship between forward current (I_F) and forward voltage (V_F), which is exponential and crucial for designing current-limiting circuits. The relationship between luminous intensity and forward current is generally linear within the operating range but may saturate at higher currents due to thermal effects. The temperature dependence of luminous intensity shows a decrease in output as junction temperature rises, a critical factor for thermal management in high-power or high-density applications. The spectral distribution curve centers around the peak wavelength of 523nm with the specified half-width.

6. Assembly and Handling Guidelines

6.1 Soldering Process

The device is compatible with infrared (IR) reflow soldering for lead-free processes. A suggested profile, compliant with J-STD-020B, includes a preheat stage (150-200°C, max 120 sec), a peak temperature not exceeding 260°C, and a time above liquidus (TAL) of 10 seconds maximum. Soldering should be limited to a maximum of two reflow cycles. For manual rework, a soldering iron at a maximum of 300°C can be applied for no more than 3 seconds, once only. Adherence to the solder paste manufacturer's specifications is essential.

6.2 Cleaning

If cleaning is necessary after soldering, only specified alcohol-based solvents like ethyl alcohol or isopropyl alcohol should be used. The LED should be immersed at normal temperature for less than one minute. Unspecified chemicals may damage the epoxy package.

6.3 Storage and Moisture Sensitivity

As a Moisture Sensitivity Level 3 (MSL3) device, it has a floor life of 168 hours (1 week) after the sealed moisture-proof bag is opened, under conditions of ≤30°C/60% RH. For storage beyond this period or outside the original packaging, baking at 60°C for at least 48 hours is required before reflow to prevent popcorn cracking during soldering. For long-term storage out of bag, use a sealed container with desiccant or a nitrogen ambient.

7. Packaging and Reel Specifications

The LEDs are supplied in embossed carrier tape with a width of 8mm. The tape is wound onto a standard 7-inch (178mm) diameter reel. Each reel contains 2000 pieces. The tape has a cover tape to seal the component pockets. Packaging conforms to ANSI/EIA-481 specifications. The maximum allowable number of consecutive missing components on a reel is two.

8. Application Design Considerations

8.1 Drive Circuit Design

LEDs are current-driven devices. To ensure consistent brightness and longevity, a constant current source or a current-limiting resistor in series with a voltage source must be used. The resistor value can be calculated using Ohm's Law: R = (V_supply - V_F) / I_F. Using the typical V_F of 3.3V and a desired I_F of 20mA from a 5V supply, R = (5V - 3.3V) / 0.02A = 85Ω. A standard 82Ω or 100Ω resistor would be appropriate. When connecting multiple LEDs in parallel, individual current-limiting resistors for each LED are strongly recommended to prevent current hogging due to natural variations in V_F.

8.2 Thermal Management

While the power dissipation is relatively low (80mW), effective thermal design on the PCB is still important, especially in high ambient temperatures or enclosed spaces. The recommended PCB pad layout aids in heat dissipation. Ensuring adequate copper area around the thermal pads and possible use of thermal vias can help maintain a lower junction temperature, preserving luminous output and device lifetime.

8.3 Optical Integration

The 120-degree diffused viewing angle provides a wide, soft emission pattern suitable for indicator applications where visibility from multiple angles is required. For light guide or backlight applications, the diffused nature of the lens may require specific optical design to achieve desired uniformity. The green color, defined by its dominant wavelength bin, is suitable for status indicators (e.g., power on, active mode) and general illumination where color differentiation is needed.

9. Reliability and Operational Notes

This product is intended for standard commercial and industrial electronic equipment. For applications requiring exceptional reliability where failure could risk safety (e.g., aviation, medical life-support, transportation control), specific qualification and consultation with the manufacturer are necessary prior to design-in. The device is not designed to be operated under reverse bias conditions. Exceeding the absolute maximum ratings, especially forward current or power dissipation, will accelerate degradation and can cause catastrophic failure.

10. Technology and Market Context

10.1 Underlying Technology Principle

This LED is based on InGaN (Indium Gallium Nitride) semiconductor material. When a forward voltage is applied, electrons and holes recombine in the active region of the semiconductor, releasing energy in the form of photons. The specific ratio of indium to gallium in the alloy determines the bandgap energy and thus the wavelength of the emitted light, which in this case is in the green spectrum (~523nm). The diffused lens is made of epoxy or silicone with scattering particles embedded to broaden the beam angle.

10.2 Comparative Advantages

Compared to older technologies like AlGaInP-based green LEDs, InGaN offers higher efficiency and better performance stability. The SMD package provides significant advantages over through-hole LEDs: smaller footprint, lower profile, suitability for automated assembly, and better compatibility with high-volume reflow soldering processes, leading to lower overall manufacturing costs.

10.3 Industry Trends

The market for SMD LEDs continues to grow, driven by miniaturization, energy efficiency demands, and the proliferation of indicator and backlighting applications in consumer electronics and IoT devices. Trends include further increases in luminous efficacy (more light output per watt), tighter binning tolerances for color and brightness consistency in display applications, and the development of even smaller package sizes. The shift towards lead-free and halogen-free materials in compliance with global environmental regulations is also a standard practice.