PLCC-3 Green LED Datasheet - Package 3.2x2.8x1.9mm - Voltage 2.75-3.65V - Power 110mW - English Technical Document

1. Product Overview

This document details the specifications for a high-performance green LED housed in a PLCC-3 surface-mount package. The device is engineered for applications requiring reliable indicators and efficient backlighting solutions. Its core advantages stem from a combination of high luminous output, a wide viewing angle facilitated by an integrated inter-reflector design, and robust construction suitable for automated assembly processes.

The primary target markets include consumer electronics, office automation equipment, and industrial control panels where clear visual signaling and space-efficient backlighting for LCDs, switches, and symbols are required. The low current requirement also makes it ideal for battery-powered portable devices.

2. In-Depth Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device's operational limits are defined to ensure long-term reliability. The maximum reverse voltage is 5V, beyond which the semiconductor junction may be damaged. The continuous forward current rating is 30mA, with a peak forward current capability of 100mA for pulsed operation (1/10 duty cycle at 1kHz). The maximum power dissipation is 110mW at an ambient temperature (T_A) of 25°C. The device can withstand an electrostatic discharge (ESD) of 150V (Human Body Model). The operating temperature range is from -40°C to +85°C, and storage conditions range from -40°C to +90°C.

2.2 Electro-Optical Characteristics

Key performance parameters are measured at a standard test current of 30mA. The luminous intensity (I_v) has a typical range from 715mcd to 1800mcd, categorized into bins. The viewing angle (2θ_1/2) is a wide 120 degrees, providing broad visibility. The dominant wavelength (λ_d) defines the green color and ranges from 520nm to 535nm. The forward voltage (V_F) typically falls between 2.75V and 3.65V at the test current. Tolerances are specified as ±10% for luminous intensity, ±1nm for dominant wavelength, and ±0.1V for forward voltage.

3. Binning System Explanation

To ensure color and brightness consistency in production, the LEDs are sorted into bins based on key parameters.

3.1 Dominant Wavelength Binning

The green color is categorized into three bins: Bin Code X (520-525nm), Y (525-530nm), and Z (530-535nm). This allows designers to select LEDs with a specific shade of green for their application.

3.2 Luminous Intensity Binning

Brightness is sorted into four bins: V1 (715-900mcd), V2 (900-1120mcd), W1 (1120-1420mcd), and W2 (1420-1800mcd). This enables selection based on the required brightness level.

3.3 Forward Voltage Binning

The operating voltage is grouped into three bins: E5 (2.75-3.05V), 6 (3.05-3.35V), and 7 (3.35-3.65V). This is crucial for designing stable current-drive circuits, especially when multiple LEDs are connected in series.

4. Performance Curve Analysis

While specific graphical curves are referenced in the datasheet, their implications are critical. The typical forward current vs. forward voltage (I-V) curve shows the exponential relationship, highlighting the need for current-limiting resistors. The luminous intensity vs. forward current curve demonstrates how output increases with current, up to the maximum rating. The spectral distribution curve confirms the peak and dominant wavelengths, defining the purity of the green color. Understanding these curves is essential for optimizing drive conditions and predicting performance under different operating scenarios.

5. Mechanical and Package Information

5.1 Package Dimensions

The PLCC-3 package has nominal dimensions of 3.2mm in length, 2.8mm in width, and 1.9mm in height. All unspecified tolerances are ±0.1mm. The package features a white body and a colorless clear lens.

5.2 Polarity Identification and Pad Layout

The cathode is typically marked. A recommended solder pad footprint is provided to ensure proper soldering, mechanical stability, and heat dissipation during reflow processes. Adhering to this layout is vital for manufacturing yield and reliability.

6. Soldering and Assembly Guidelines

The device is suitable for both reflow and wave soldering processes. For reflow soldering, the maximum peak temperature should not exceed 260°C for a duration of 10 seconds. For hand soldering, the iron tip temperature should be limited to 350°C for a maximum of 3 seconds per lead. These limits prevent thermal damage to the plastic package and the internal die and wire bonds.

7. Packaging and Ordering Information

The LEDs are supplied on 8mm carrier tape, wound onto reels. Each reel contains 2000 pieces. The packaging includes moisture-resistant measures: the reel is placed inside an aluminum moisture-proof bag along with a desiccant, and a humidity indicator card is included. The product label explains the binning codes for luminous intensity (CAT), dominant wavelength (HUE), and forward voltage (REF).

8. Application Recommendations

8.1 Typical Application Scenarios

This LED is ideal for status indicators and backlighting in audio/video equipment, home appliances, and office machines. Its wide viewing angle and efficient light coupling make it particularly suitable for use with light pipes to guide light to specific panel locations. It is also used for flat backlighting of LCDs, membrane switches, and illuminated symbols.

8.2 Critical Design Considerations

Current Limiting is Mandatory: An external series resistor must always be used to limit the forward current. The LED's exponential I-V characteristic means a small increase in voltage can cause a large, destructive increase in current. The resistor value should be calculated based on the supply voltage, the LED's forward voltage (considering the bin and temperature effects), and the desired operating current (not to exceed 30mA continuous).

Thermal Management: While the package can dissipate 110mW, operating at high ambient temperatures or at maximum current will increase junction temperature, which can reduce light output and lifespan. Adequate PCB copper area around the pads can help with heat sinking.

9. Technical Comparison and Differentiation

Compared to simpler LED packages, the key differentiator of this PLCC-3 device is the integrated inter-reflector. This feature captures and redirects side-emitting light upwards, significantly enhancing the viewing angle and the total light output efficiency from the top surface. This makes it superior to basic chip LEDs for applications requiring wide-angle visibility or when coupled with light pipes. The package is also more robust and easier for automated pick-and-place machines to handle than two-lead packages.

10. Frequently Asked Questions (FAQs)

Q: Can I drive this LED directly from a 5V supply?
A: No. You must use a current-limiting resistor. For example, with a 5V supply, an LED V_F of 3.0V (typical), and a desired I_F of 20mA, the resistor value would be R = (5V - 3.0V) / 0.020A = 100Ω. The resistor power rating should be at least I²R = (0.02)² * 100 = 0.04W, so a 1/8W or 1/4W resistor is suitable.

Q: What is the difference between peak wavelength and dominant wavelength?
A> Peak wavelength (λ_P) is the wavelength at which the spectral power distribution is maximum. Dominant wavelength (λ_d) is the single wavelength of monochromatic light that matches the perceived color of the LED. Dominant wavelength is more relevant for color specification.

Q: How do I interpret the bin codes on the label?
A: The label codes (e.g., from the Device Selection Guide) indicate the specific performance bin for that batch of LEDs. "CAT" refers to the luminous intensity bin (e.g., W2), "HUE" to the dominant wavelength bin (e.g., Y), and "REF" to the forward voltage bin (e.g., 6). This allows for precise selection and matching in production.

11. Design and Usage Case Study

Scenario: Backlighting a Membrane Switch Panel. A designer needs to evenly illuminate four symbols on a control panel using a single LED due to space constraints. They select this PLCC-3 green LED for its high brightness and wide viewing angle. A custom acrylic light pipe is designed with four branches to channel light from the centrally mounted LED to each symbol. The wide 120-degree viewing angle of the LED ensures efficient coupling of light into the entrance of the light pipe. The LED is driven at 25mA via a current-limiting resistor from a 3.3V microcontroller rail. The chosen luminous intensity bin (W1) provides sufficient brightness even after losses in the light pipe. The consistent color from the wavelength bin (Y) ensures all four symbols have the same green hue.

12. Operational Principle

This is a semiconductor light-emitting diode. When a forward voltage exceeding the junction's threshold is applied, electrons and holes recombine in the active region of the InGaN (Indium Gallium Nitride) chip. This recombination process releases energy in the form of photons, producing light. The specific composition of the semiconductor materials determines the wavelength (color) of the emitted light, in this case, green. The plastic package serves to protect the chip, provide a primary lens to shape the light output, and incorporate reflective surfaces to improve efficiency.

13. Industry Trends

The market for SMD LEDs like the PLCC-3 continues to evolve. General trends include the push for even higher luminous efficacy (more light output per watt of electrical input), which improves energy efficiency. There is also a focus on enhancing color consistency and stability over temperature and lifetime. Furthermore, packaging technology advances aim to make devices even smaller while maintaining or improving optical performance and reliability, catering to the miniaturization of electronic devices. The principles of wide viewing angle and efficient light extraction, as seen in this device's inter-reflector design, remain central to these developments.