Yellow PLCC4 LED Specification - 3.5x2.8x1.85mm - 2.0-2.6V - 182mW - 590nm Dominant Wavelength

1. Product Overview

1.1 General Description

This Yellow LED is based on AlGaInP (Aluminum Gallium Indium Phosphide) epitaxial layers grown on a substrate and packaged in a PLCC4 (Plastic Leaded Chip Carrier) configuration. The compact package measures 3.50mm x 2.80mm x 1.85mm (length x width x height), making it suitable for space-constrained applications. The device emits a yellow light with a dominant wavelength centered at approximately 590nm. It is designed for general illumination and automotive lighting applications where high brightness and reliability are required.

1.2 Features

• PLCC4 package for easy SMT assembly.
• Very wide viewing angle of 120 degrees (at half intensity), enabling broad light distribution.
• Compatible with all standard SMT assembly and reflow soldering processes.
• Available in tape and reel packaging for automated pick-and-place.
• Moisture sensitivity level 2 (MSL 2) per JEDEC standards.
• Compliant with RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations.
• Qualified according to AEC-Q101 stress test qualification for automotive-grade discrete semiconductors.

1.3 Applications

• Automotive interior lighting (e.g., dashboard indicators, ambient lighting).
• Automotive exterior lighting (e.g., turn signals, brake lights, rear combination lamps).
• General indication and signage.
• Any application requiring a high-intensity yellow SMD LED with wide beam angle.

2. Package Dimensions

2.1 Mechanical Outline

The LED package has overall dimensions of 3.50mm (length) × 2.80mm (width) × 1.85mm (height). All dimensions have a tolerance of ±0.2mm unless otherwise stated. The top view shows a rectangular body with a polarity mark (chamfered corner) on the upper right. The side view indicates a total height of 1.85mm. The bottom view reveals four solder pads: pads 1 and 2 (cathode/anode) are located on the lower side, while pads 3 and 4 are on the upper side. For detailed arrangement, refer to the polarity diagram which shows the connection scheme. The recommended soldering pattern (land pattern) on the PCB is also provided to optimize thermal and electrical performance. The pattern dimensions are: a central rectangular area of 2.60mm × 1.60mm, with extended pads of 4.60mm overall length and 0.80mm width for the outer connections. This pattern ensures reliable solder joint formation and adequate heat dissipation.

3. Electrical and Optical Characteristics

3.1 Electrical/Optical Parameters at 25°C (IF=50mA unless noted)

3.2 Absolute Maximum Ratings (Ts=25°C unless noted)

3.3 Binning Information at IF=50mA

The LEDs are sorted into bins based on forward voltage (V_F), luminous intensity (I_V), and dominant wavelength (λ_D). The binning ranges are as follows:

Forward Voltage Bins: C1 (2.0-2.1V), C2 (2.1-2.2V), D1 (2.2-2.3V), D2 (2.3-2.4V), E1 (2.4-2.5V), E2 (2.5-2.6V).

Luminous Intensity Bins: N1 (1800-2300 mcd), N2 (2300-2800 mcd), O1 (2800-3500 mcd).

Dominant Wavelength Bins: A2 (584.5-587 nm), B1 (587-589.5 nm), B2 (589.5-592 nm), C1 (592-594.5 nm).

The bin code is marked on the product label and can be used to select specific performance ranges for the application.

4. Typical Optical Characteristics Curves

4.1 Forward Voltage vs. Forward Current

As the forward current increases from 0 to 70 mA, the forward voltage rises from approximately 1.9V to 2.6V. The curve follows the typical exponential diode characteristic. At the test condition of 50 mA, the forward voltage is typically 2.3V.

4.2 Relative Intensity vs. Forward Current

The relative luminous intensity increases nearly linearly with forward current up to 70 mA. At 50 mA, the relative intensity is approximately 90% of the maximum at 70 mA. This behavior allows fine-tuning brightness by adjusting the drive current within the rated range.

4.3 Solder Temperature vs. Relative Luminous Flux

As the solder temperature (Ts) increases from 25°C to 120°C, the relative luminous flux decreases. At 100°C, the flux drops to about 75% of the value at 25°C. Thermal management is therefore critical to maintain consistent light output.

4.4 Solder Temperature vs. Forward Current Derating

To keep the junction temperature within limits, the maximum allowable forward current must be derated as the ambient/solder temperature rises. At Ts=100°C, the maximum forward current is reduced to about 40 mA, compared to 70 mA at 25°C.

4.5 Forward Voltage vs. Solder Temperature

The forward voltage decreases slightly with increasing temperature. Over the range of 25°C to 120°C, the forward voltage drops by approximately 0.2V. This negative temperature coefficient should be considered when designing constant-current or constant-voltage drivers.

4.6 Radiation Pattern

The radiation pattern is nearly Lambertian with a wide half-angle of 120°. The relative intensity is maximum at 0° (on-axis) and falls to 50% at ±60°. The pattern is symmetric and provides uniform light distribution in the intended application.

4.7 Dominant Wavelength vs. Forward Current

As the forward current increases from 0 to 70 mA, the dominant wavelength shifts slightly toward longer wavelengths (red shift). The shift is approximately 1 nm over the full current range, which is negligible for most applications but can be considered for color-critical designs.

4.8 Spectrum Distribution

The spectrum shows a single peak centered around 590 nm with a full width at half maximum (FWHM) of approximately 20 nm. The emission is in the yellow region of the visible spectrum, with no significant secondary peaks. The spectral purity is high, making this LED suitable for applications requiring a specific yellow color.

5. Packaging Information

5.1 Carrier Tape and Reel Dimensions

The LEDs are packaged in carrier tape with a pitch of 4.00 mm and a width of 8.00 mm. The tape features a pocket that accommodates the 3.5×2.8mm package and a cover tape for protection. Each reel holds 2000 pieces. The reel outer diameter is 330 mm, the hub diameter is 100 mm, and the spindle hole diameter is 13 mm. The tape feed direction is indicated by arrows on the reel.

5.2 Label and Moisture Protection

Each reel is labeled with the part number, specification number, lot number, bin code, luminous flux code (or intensity), chromaticity bin, forward voltage code, wavelength code, quantity, and date code. The reel is placed inside a moisture barrier bag with a desiccant and a humidity indicator card. The bag is then sealed to maintain a low‑moisture environment. The outer cardboard box contains multiple reels for shipping.

6. Reliability Test Items and Conditions

Failure Criteria: After the tests, the following limits apply: Forward voltage change ≤ 1.1 times the upper specification limit (USL). Reverse current ≤ 2.0 times USL. Luminous flux ≥ 0.7 times the lower specification limit (LSL).

7. SMT Reflow Soldering Instructions

7.1 Recommended Reflow Profile

The LED is suitable for lead‑free reflow soldering. The following profile should be used:

• Preheat: 150°C to 200°C for 60‑120 seconds.
• Ramp-up from Tsmax to TL (217°C) at a rate ≤ 3°C/s.
• Time above 217°C (tL): 60‑120 seconds.
• Peak temperature (TP): 260°C, with a maximum time within 5°C of peak (tp) of 10 seconds.
• Ramp-down from peak to 25°C at a rate ≤ 6°C/s.
• Total time from 25°C to peak: ≤ 8 minutes.

Do not exceed two reflow cycles. If the time between two reflow operations exceeds 24 hours, the LEDs must be baked to avoid moisture damage. Do not apply mechanical stress to the LED during heating.

7.2 Hand Soldering

If hand soldering is necessary, use a soldering iron set below 300°C and complete the joint within 3 seconds. Only one hand‑soldering operation is allowed.

7.3 Rework

Rework after soldering is not recommended. If unavoidable, use a dual‑head hot‑air tool to simultaneously heat both joints and carefully remove the component. Confirm that rework does not damage the LED's characteristics.

7.4 Cautions

• The LED encapsulant is silicone, which has a soft surface. Avoid applying strong pressure on the top surface, as it may affect reliability. Use appropriate pickup nozzles with controlled force.
• Do not mount the LED on a warped PCB. After soldering, avoid bending the PCB.
• Do not apply mechanical force or vibration during cooling after soldering. Do not quench the device rapidly.

8. Handling Precautions

8.1 Environmental Compatibility

The materials in contact with the LED must not contain sulfur compounds exceeding 100 ppm. The total content of bromine and chlorine in surrounding materials should be below 1500 ppm, with each element individually below 900 ppm. Volatile organic compounds (VOCs) can penetrate the silicone encapsulant and cause discoloration under heat and light. Therefore, only compatible materials should be used in the fixture construction. Refond recommends testing all chemicals and adhesives in the intended environment before use.

8.2 Handling and Assembly

Always handle the LED by its side surfaces using tweezers or appropriate tools. Avoid touching the silicone lens directly to prevent damage to the internal circuitry. When picking and placing, use a nozzle that does not deform the silicone surface.

8.3 Circuit Design

Design the driving circuit to ensure the current through each LED does not exceed the absolute maximum rating (70 mA DC). Include a series resistor to limit current and compensate for voltage variations. Do not apply reverse voltage to the LED, as it can cause migration and permanent damage. Provide ESD protection (HBM up to 2 kV) during handling and assembly.

8.4 Thermal Design

Since LED characteristics degrade with increasing junction temperature (e.g., reduced brightness, color shift), adequate thermal management is essential. Ensure that the PCB has sufficient copper area and thermal vias to dissipate heat. The junction temperature must not exceed 120°C.

8.5 Cleaning

If cleaning is required after soldering, isopropyl alcohol is recommended. Other solvents must be verified to not attack the package or resin. Ultrasonic cleaning is not recommended as it may damage the LED.

8.6 Storage Conditions

If the moisture barrier bag is damaged or the humidity indicator shows excessive moisture, bake the LEDs at 60±5°C for at least 24 hours before use.

8.7 Electrostatic Discharge (ESD)

This LED is sensitive to ESD. More than 90% of units survive 2000 V HBM. However, proper ESD precautions (grounded workstations, wrist straps, conductive containers) must be taken during handling and assembly to avoid latent damage.