Blue LED 2.8x3.5x0.65mm 3.4V 0.3W Plant Growth PLCC-2 Technical Datasheet Guide

1. Product Overview

This product utilizes a PLCC-2 package with compact outline dimensions of 2.8 x 3.5 x 0.65 mm. It is a blue LED designed for plant growth applications, featuring a peak wavelength of 450 nm and a wide viewing angle of 120°. The LED is optimized for high radiant flux output at a forward current of 100 mA, making it suitable for horticultural lighting, tissue culture, and plant factory systems. Key features include compatibility with all SMT assembly and soldering processes, availability on tape and reel packaging, moisture sensitivity level 3, and RoHS compliance. The device's design balances efficiency and reliability, enabling extended operation in demanding agricultural environments.

1.1 Features

• PLCC-2 package for compact design.
• Wide 120° viewing angle for uniform light distribution.
• Compatible with standard SMT assembly processes.
• Available in tape and reel packaging (4000 pcs/reel).
• Moisture sensitivity level 3 (MSL 3).
• RoHS compliant for environmental safety.

1.2 Applications

• Flower production lighting.
• Tissue culture and micropropagation.
• Vertical farming and plant factories.
• Supplemental lighting for greenhouses.
• General horticultural lighting.

2. Technical Parameters and In-depth Analysis

2.1 Electrical and Optical Characteristics (at Ts=25°C, IF=100mA)

The table below summarizes the key electrical and optical parameters measured at a solder temperature of 25°C and a forward current of 100 mA (unless otherwise noted).

• Forward Voltage (VF): Typical 3.4 V, minimum 2.8 V, maximum 3.6 V. Measurement tolerance is ±0.1 V.
• Reverse Current (IR): At VR=5 V, reverse current is very low (typically negligible), maximum 10 μA.
• Total Radiant Flux (Φe): Minimum 140 mW, typical 180 mW, maximum 224 mW. Tolerance ±10%.
• Peak Wavelength (λp): Minimum 440 nm, typical 450 nm, maximum 455 nm. Tolerance ±2 nm.
• Viewing Angle (2θ½): 120° typical, providing a wide light distribution.
• Thermal Resistance (RthJ-S): 15 °C/W typical, indicating good heat transfer from junction to solder point.

2.2 Absolute Maximum Ratings

These values must not be exceeded to avoid permanent damage:

• Power Dissipation (PD): 0.3 W
• Forward Current (IF): 100 mA (DC); Peak Forward Current (IFP) 150 mA at 1/10 duty cycle, 0.1 ms pulse width.
• Reverse Voltage (VR): 5 V
• Electrostatic Discharge (ESD, HBM): 2000 V (yield >90%)
• Operating Temperature (TOPR): -40°C to +85°C
• Storage Temperature (TSTG): -40°C to +100°C
• Junction Temperature (TJ): 115°C maximum

Care must be taken to ensure that the junction temperature does not exceed the rated value. The maximum current should be determined after measuring the package temperature under actual operating conditions.

2.3 Binning System

Products are sorted into bins based on forward voltage (VF), total radiant flux (Φe), and peak wavelength (WLP). The label on each reel specifies the bin code, allowing customers to select LEDs with matched characteristics for consistent performance in arrays. Typical bin ranges for VF are 2.8–3.6 V; for radiant flux, 140–224 mW; and for wavelength, 440–455 nm. This binning ensures uniformity in color and output for high-quality lighting systems.

3. Performance Curves Analysis

3.1 Forward Voltage vs. Forward Current

Figure 1 shows the relationship between forward voltage and forward current at room temperature. As current increases from 0 to 150 mA, forward voltage rises approximately from 2.9 V to 3.4 V. This curve is essential for designing current-regulated drivers to maintain stable light output.

3.2 Relative Intensity vs. Forward Current

Figure 2 illustrates the relative radiant power as a function of forward current. The output increases linearly with current up to about 80 mA, then gradually saturates at higher currents due to thermal effects. Operating near 100 mA provides a good balance between efficiency and flux.

3.3 Temperature Dependence

Figure 3 shows the relative power output versus solder temperature (Ts). At higher temperatures, the relative intensity decreases; for example, at 85°C the output drops to approximately 80% of the value at 25°C. This thermal droop must be accounted for in system thermal management.

Figure 4 displays the maximum allowable forward current as a function of Ts. To prevent overheating, the current must be derated as ambient temperature rises. At Ts=85°C, the maximum current is reduced to about 80 mA.

3.4 Spectrum Distribution

Figure 5 presents the spectral emission curve. The peak wavelength is centered at 450 nm with a full width at half maximum (FWHM) of approximately 20 nm. This narrow blue band is ideal for triggering specific photoreceptors in plants such as cryptochromes and phototropins, promoting photosynthesis and photomorphogenesis.

3.5 Radiation Pattern

Figure 6 depicts the far-field radiation pattern. At ±60° relative to the optical axis, the intensity drops to 50% of the peak, confirming the 120° viewing angle. This wide distribution is beneficial for uniform illumination in plant canopies.

4. Mechanical and Packaging Information

4.1 Package Dimensions

The LED is housed in a PLCC-2 package with dimensions 2.8 mm (length) x 3.5 mm (width) x 0.65 mm (height). All tolerances are ±0.2 mm unless otherwise noted. The top view shows a lens diameter of 2.48 mm. The bottom view indicates a rectangular pad layout with two electrodes: the anode (longer pad) and cathode (shorter pad). Polarity is marked with a "+" symbol on the package.

4.2 Soldering Patterns

Recommended solder pad dimensions are provided in the mechanical drawing (Fig.1-5). The total pad area is approximately 2.1 mm x 2.1 mm per electrode, with a pitch of 3.5 mm. Proper soldering footprint ensures reliable mechanical and thermal connection.

5. Soldering and Assembly Guidelines

5.1 Reflow Soldering Profile

A standard lead-free reflow profile is recommended. Key parameters: preheat from 150°C to 200°C for 60–120 seconds; time above liquidus (217°C) up to 60 seconds; peak temperature 260°C for up to 10 seconds; cooling rate less than 6°C/s. The total time from 25°C to peak should not exceed 8 minutes. Do not reflow more than twice. If more than 24 hours elapse between reflows, the LEDs may be damaged.

5.2 Hand Soldering

If manual soldering is necessary, keep the iron temperature below 300°C and contact time under 3 seconds. Only one soldering attempt is allowed. After soldering, avoid mechanical stress or rapid cooling.

5.3 Repair

Repair is generally not recommended. If unavoidable, use a double-head soldering iron to heat both pads simultaneously, and verify LED functionality afterward.

5.4 Cautions

The encapsulation material is silicone, which is soft. Avoid pressing on the lens surface. Use appropriate pickup nozzles with controlled force. Do not mount LEDs on warped PCBs and avoid bending the board after soldering.

6. Packaging and Ordering Information

6.1 Packaging Specification

Each reel contains 4000 pieces. The carrier tape has a pitch of 4 mm and width of 12 mm, with polarity marks for orientation. The reel diameter is 178 mm, hub diameter 60 mm, and tape width 12 mm. A label on the reel provides part number, spec number, lot number, bin code for radiant flux, forward voltage range, wavelength bin, quantity, and date.

6.2 Moisture Barrier Bag

The reels are sealed in a moisture barrier bag with desiccant and a humidity indicator card. Storage conditions before opening: temperature ≤30°C, humidity ≤75% RH, shelf life up to one year. After opening, LEDs must be used within 24 hours at ≤30°C/≤60% RH. If exceeded, bake at 60°C for 24 hours before use.

7. Application Recommendations

This blue LED is specifically designed for plant growth lighting. Its 450 nm peak matches the absorption peaks of chlorophyll a, chlorophyll b, and carotenoids, enhancing photosynthetic efficiency. For optimal performance, use a constant current driver with ripple less than 5%. The maximum operating current should be derated based on ambient temperature and thermal resistance. Ensure good heat sinking by mounting the LED on a metal-core PCB or using nearby thermal vias. Avoid exposure to sulfur-containing compounds and volatile organic compounds (VOCs) that can cause discoloration or lumen loss. Maintain a clean environment during assembly to prevent dust attraction on the silicone lens.

8. Technical Comparison

Compared to standard 2835 SMD LEDs, the PLCC-2 package offers a smaller footprint (2.8x3.5 mm vs 2.8x3.5 mm for 2835, but note that PLCC-2 is similar in size) but with a higher radiant flux per package (180 mW typical at 100 mA) compared to typical 2835 blue LEDs (~100 mW). The wide 120° viewing angle also provides better spatial uniformity. The low thermal resistance (15°C/W) facilitates heat dissipation, making this LED suitable for high-density arrays in plant factories. The ESD withstand capability of 2000V (HBM) is comparable to industry standards.

9. Frequently Asked Questions

Q1: What is the maximum forward current I can apply? A: The absolute maximum rating is 100 mA DC, but consider derating at high ambient temperatures. For reliable operation, 80-90 mA is recommended to balance lifetime and output.

Q2: How should I handle the LED to avoid ESD damage? A: Use proper ESD protection equipment (grounded wrist strap, conductive tables, ionizers) during handling. The LED can withstand up to 2000V HBM, but caution is still needed.

Q3: Can I use this LED for general illumination? A: Yes, but it emits blue light only. For white light, combine with phosphor or other color LEDs.

Q4: What is the recommended storage condition for unopened reels? A: Temperature ≤30°C, humidity ≤75% RH. Shelf life is one year from date of packaging.

10. Practical Case Studies

In a vertical farming setup, a panel of 200 such blue LEDs was used to provide supplemental lighting for lettuce cultivation. At a drive current of 80 mA, the total radiant flux reached 36 W (200*0.18 W). The LED panel was placed 20 cm above the canopy, achieving a PPFD (photosynthetic photon flux density) of approximately 150 μmol/m²/s at the canopy level. The resulting lettuce biomass increased by 30% compared to ambient light alone. The LEDs operated at 45°C junction temperature, well within the safe limit.

Another case: in a tissue culture laboratory, arrays of these LEDs were used for micropropagation of orchids. The pure blue spectrum minimized etiolation and promoted root development. The 120° viewing angle allowed uniform illumination across the culture shelves without hot spots.

11. Operating Principle

This LED is a gallium nitride (GaN)-based blue light-emitting diode. When a forward bias is applied across the p-n junction, electrons from the n-type layer recombine with holes in the p-type layer within the active region. This recombination releases energy in the form of photons. The bandgap energy of the InGaN quantum well structure is tailored to produce light at approximately 450 nm (blue). The PLCC-2 package encapsulates the chip and provides electrical contacts and thermal paths. The silicone lens protects the chip and extracts light efficiently.

12. Development Trends

The horticultural LED market is rapidly evolving. Future trends include higher efficacy (>3 μmol/J), tunable spectra combining multiple wavelengths, and integration with smart controls. PLCC-2 packages are expected to shrink further while increasing power density. The current generation of blue LEDs already achieves radiant fluxes above 200 mW per package at 100 mA. Research into InGaN materials and chip designs promises even better performance. Additionally, efforts to reduce costs and improve reliability will drive adoption in large-scale plant factories.