SMT LED Yellow-Green 1.6x0.8x0.7mm - Forward Voltage 1.8-2.4V - Power 72mW - Technical Specification

1. Product Overview

This specification describes a surface-mount yellow-green LED with a compact package dimension of 1.6 mm × 0.8 mm × 0.7 mm. The LED is fabricated using a yellow-green chip, providing a dominant wavelength range from 567.5 nm to 575.0 nm. It is designed for general optical indication, switch and symbol display, and other common applications. The LED features an extremely wide viewing angle of 140°, making it suitable for applications where uniform light distribution is required. It is RoHS compliant and has a moisture sensitivity level of 3, ensuring compatibility with standard SMT assembly and reflow soldering processes.

1.1 Key Features

• Extremely wide viewing angle (2θ1/2 = 140°) for broad light distribution.
• Suitable for all SMT assembly and solder processes.
• Moisture sensitivity level: Level 3 (MSL3).
• RoHS compliant, environmentally friendly.

1.2 Applications

• Optical indicators (e.g., status lights, backlight).
• Switches, symbols, and displays.
• General purpose illumination and signaling.

2. Technical Parameters Detailed Analysis

The electrical and optical characteristics are specified at an ambient temperature of Ts = 25 °C and a forward current of 20 mA unless otherwise noted.

2.1 Electrical and Optical Characteristics (Table 1-1)

• Forward Voltage (VF): The LED is binned into six voltage groups: B1 (1.8-1.9 V), B2 (1.9-2.0 V), C1 (2.0-2.1 V), C2 (2.1-2.2 V), D1 (2.2-2.3 V), D2 (2.3-2.4 V). Typically, forward voltage ranges from 1.8 V to 2.4 V.
• Dominant Wavelength (λD): Binned into three groups: B20 (567.5-570.0 nm), C10 (570.0-572.5 nm), C20 (572.5-575.0 nm). The typical half bandwidth (spectral half bandwidth) is 15 nm.
• Luminous Intensity (IV): Binned into four groups: B00 (12-18 mcd), C00 (18-28 mcd), D00 (28-43 mcd), E00 (43-65 mcd). Measurements are made at 20 mA.
• Viewing Angle: 2θ1/2 = 140° typical.
• Reverse Current (IR): At VR = 5 V, maximum 10 μA.
• Thermal Resistance (RTHJ-S): Maximum 450 °C/W (junction to solder point).

2.2 Absolute Maximum Ratings (Table 1-2)

These limits must not be exceeded even momentarily. Pulse conditions: 1/10 duty cycle, 0.1 ms pulse width.

3. Binning System

The LED is classified into multiple bins to ensure consistent performance for customers:

• Voltage Bins: B1, B2, C1, C2, D1, D2 – covering 1.8 V to 2.4 V in 0.1 V steps.
• Wavelength Bins: B20, C10, C20 – covering 567.5 nm to 575.0 nm in 2.5 nm steps.
• Luminous Intensity Bins: B00, C00, D00, E00 – covering 12 mcd to 65 mcd.

This binning allows customers to select LEDs with tightly controlled electrical and optical performance for their specific applications.

4. Performance Curves Analysis

The typical optical characteristics curves (Fig. 1-6 to Fig. 1-12) provide insight into the LED behavior under various conditions:

• Forward Voltage vs. Forward Current (Fig. 1-6): Shows the exponential relationship; voltage increases with current.
• Forward Current vs. Relative Intensity (Fig. 1-7): Relative luminous intensity increases with forward current, nearly linear within the operating range.
• Pin Temperature vs. Relative Intensity (Fig. 1-8): Intensity decreases as pin temperature rises due to reduced radiative efficiency.
• Pin Temperature vs. Forward Current (Fig. 1-9): Derating curve – maximum allowable current reduces at high temperatures.
• Forward Current vs. Dominant Wavelength (Fig. 1-10): Wavelength shifts slightly with current (red-shift at higher currents).
• Relative Intensity vs. Wavelength (Fig. 1-11): Spectral distribution shows a peak around 570 nm with a half bandwidth of ~15 nm.
• Radiation Pattern (Fig. 1-12): Wide angular distribution (140°) ensures uniform light emission.

These curves assist designers in predicting LED performance in different thermal and electrical conditions.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED package is 1.6 mm (length) × 0.8 mm (width) × 0.7 mm (height). Tolerances are ±0.2 mm unless otherwise specified. The bottom view shows two pads: Pad 1 (cathode) and Pad 2 (anode), with polarity markings. Recommended soldering pads have dimensions: each pad 0.8 mm × 0.8 mm, with 2.4 mm spacing between centers.

5.2 Polarity and Soldering Patterns

The polarity is indicated by a notch on the package (Fig. 1-4). Correct orientation must be ensured during placement. The recommended soldering land pattern (Fig. 1-5) helps achieve reliable solder joints and proper heat dissipation.

6. Soldering and Assembly Guide

6.1 Reflow Soldering Profile

The recommended reflow soldering profile (Fig. 3-1) is as follows:

• Average ramp-up rate: ≤3 °C/s (from Tsmax to TP).
• Preheating: 150 °C to 200 °C for 60-120 s.
• Time above 217 °C (TL): ≤60 s.
• Peak temperature (TP): 260 °C, with time within 5 °C of peak (tp) ≤30 s.
• Cooling rate: ≤6 °C/s.
• Total time from 25 °C to peak: ≤8 minutes.

Reflow soldering should not be performed more than twice. If more than 24 hours elapse between two soldering operations, the LEDs may absorb moisture and be damaged.

6.2 Hand Soldering and Repair

Hand soldering: iron temperature ≤300 °C, time ≤3 seconds, one time only. Repair should be avoided; if necessary, use a double-head soldering iron and pre-validate the effect on LED characteristics.

6.3 Handling Precautions

• Do not mount LEDs on warped PCBs.
• Do not apply mechanical stress or vibration during cooling.
• Avoid rapid cooling after soldering.

7. Packaging and Ordering Information

LEDs are packaged in carrier tape and reel. Standard quantity: 4000 pcs per reel. The carrier tape has dimensions as shown in Fig. 2-1 (pitch 4.0 mm, width 8.0 mm). The reel (Fig. 2-2) has an outer diameter of 178 mm ±1 mm. A moisture barrier bag with desiccant and humidity indicator card is used. The label (Fig. 2-3) includes part number, spec number, lot number, bin codes for luminous flux, chromaticity, forward voltage, wavelength, quantity, and date. Outer cardboard box dimensions are provided (Fig. 2-5).

8. Application Recommendations

Typical applications include optical indicators on consumer electronics, automotive interior lighting, backlighting for switches, and general signage. Due to the wide viewing angle, these LEDs are ideal for status lights that need to be visible from many angles. For optimal performance, ensure adequate heat sinking and limit forward current to ≤30 mA (or lower based on thermal conditions). Use current-limiting resistors in series.

9. Reliability and Testing

The LED has been qualified according to standard reliability tests (Table 2-3):

• Reflow: 260°C max, 2 times, 22 pcs, 0/1 accept/reject.
• Temperature Cycle: -40°C to 100°C, 100 cycles, 22 pcs.
• Thermal Shock: -40°C to 100°C, 300 cycles, 22 pcs.
• High Temperature Storage: 100°C for 1000 hrs, 22 pcs.
• Low Temperature Storage: -40°C for 1000 hrs, 22 pcs.
• Life Test: 25°C, 20 mA for 1000 hrs, 22 pcs.

Failure criteria: forward voltage >1.1× USL, reverse current >2.0× USL, luminous flux <0.7× LSL.

10. Handling and Storage Precautions

• Sulfur content in the environment and mating materials should not exceed 100 ppm.
• Bromine and chlorine content in external materials: single element <900 ppm, total <1500 ppm.
• Avoid volatile organic compounds (VOCs) that may penetrate the silicone encapsulant and cause discoloration.
• ESD sensitivity: use proper ESD protection during handling.
• Storage before opening: ≤30°C, ≤75% RH, within 1 year from date. After opening: ≤30°C, ≤60% RH, 168 hours. If exceeded, bake at 60±5°C for ≥24 hours before use.

11. Principles of LED Operation

This LED is based on a gallium phosphide (GaP) yellow-green chip. When forward current is applied, electrons and holes recombine in the PN junction, releasing energy in the form of photons (electroluminescence). The wavelength (color) is determined by the semiconductor bandgap. The wide viewing angle is achieved by the package design and encapsulation.

12. Development Trends

SMT LEDs continue to shrink in size while increasing efficiency. This 1.6×0.8×0.7 mm package represents a common miniature format (similar to 0603 imperial). Future trends include higher luminous efficacy, tighter binning, and improved thermal management for higher current operation. The adoption of RoHS and environmental regulations drives the use of lead-free soldering and halogen-free materials.

13. Frequently Asked Questions

Q: What is the recommended operating current?
A: For continuous operation, 20 mA is typical. Maximum is 30 mA. Use a resistor to limit current.

Q: How should I store unused LEDs?
A: Follow the storage conditions: ≤30°C, ≤75% RH. Use within 1 year. After opening, use within 168 hours or bake before use.

Q: Can I use this LED in outdoor applications?
A: The operating temperature range is -40°C to +85°C, but the LED is not rated for direct exposure to moisture without proper conformal coating.

Q: What is the typical lifetime?
A: The reliability test includes 1000 hours life test at 20 mA, 25°C. Typical lifetime is much longer (e.g., 50,000 hours) depending on operating conditions.

14. Practical Application Examples

Example 1: A status indicator on a network switch. Use a 150 Ω series resistor with 5 V supply to achieve ~20 mA forward current. The wide viewing angle ensures visibility from all sides of the equipment.

Example 2: Backlight for a pushbutton symbol. The yellow-green color provides good contrast. Use a constant current driver to maintain consistent brightness over temperature.

Example 3: Automotive interior ambient lighting (non-safety critical). The compact size allows placement in tight spaces. Ensure thermal management via PCB copper traces.